From 9b1a5302420f81801bbd76afe07d7c56377e50c1 Mon Sep 17 00:00:00 2001
From: Dmitri Naumov <dmitri.naumov@ufz.de>
Date: Mon, 9 Jan 2017 16:41:01 +0100
Subject: [PATCH] Use #pragma once instead of cpp macros.

---
 Applications/ApplicationsLib/LinearSolverLibrarySetup.h    | 6 +-----
 Applications/ApplicationsLib/LogogSetup.h                  | 5 +----
 Applications/ApplicationsLib/ProjectData.h                 | 5 +----
 Applications/DataExplorer/Base/CheckboxDelegate.h          | 5 +----
 Applications/DataExplorer/Base/ColorPickerPushButton.h     | 5 +----
 Applications/DataExplorer/Base/ImportFileTypes.h           | 5 +----
 Applications/DataExplorer/Base/LastSavedFileDirectory.h    | 6 +-----
 Applications/DataExplorer/Base/OGSError.h                  | 5 +----
 .../DataExplorer/Base/QNonScalableGraphicsTextItem.h       | 5 +----
 Applications/DataExplorer/Base/QValueTooltipSlider.h       | 5 +----
 Applications/DataExplorer/Base/RecentFiles.h               | 5 +----
 Applications/DataExplorer/Base/StrictDoubleValidator.h     | 5 +----
 Applications/DataExplorer/Base/StrictIntValidator.h        | 5 +----
 Applications/DataExplorer/Base/TreeItem.h                  | 5 +----
 Applications/DataExplorer/Base/TreeModel.h                 | 5 +----
 Applications/DataExplorer/Base/TreeModelIterator.h         | 5 +----
 Applications/DataExplorer/Base/modeltest.h                 | 5 +----
 Applications/DataExplorer/DataView/AddLayerToMeshDialog.h  | 5 +----
 Applications/DataExplorer/DataView/BaseItem.h              | 5 +----
 Applications/DataExplorer/DataView/ColorTableModel.h       | 4 +---
 Applications/DataExplorer/DataView/ColorTableView.h        | 6 +-----
 Applications/DataExplorer/DataView/CondFromRasterDialog.h  | 5 +----
 Applications/DataExplorer/DataView/CondItem.h              | 5 +----
 Applications/DataExplorer/DataView/CondObjectListItem.h    | 5 +----
 .../DataExplorer/DataView/CreateStructuredGridDialog.h     | 5 +----
 .../DataExplorer/DataView/DataExplorerSettingsDialog.h     | 5 +----
 .../DataExplorer/DataView/DiagramView/DetailWindow.h       | 5 +----
 .../DataExplorer/DataView/DiagramView/DiagramList.h        | 5 +----
 .../DataExplorer/DataView/DiagramView/DiagramPrefsDialog.h | 5 +----
 .../DataExplorer/DataView/DiagramView/DiagramScene.h       | 5 +----
 .../DataExplorer/DataView/DiagramView/DiagramView.h        | 5 +----
 Applications/DataExplorer/DataView/DiagramView/QArrow.h    | 5 +----
 .../DataExplorer/DataView/DiagramView/QGraphicsGrid.h      | 5 +----
 .../DataExplorer/DataView/DirectConditionGenerator.h       | 6 +-----
 Applications/DataExplorer/DataView/ElementTreeModel.h      | 5 +----
 Applications/DataExplorer/DataView/ElementTreeView.h       | 7 +------
 Applications/DataExplorer/DataView/GEOModels.h             | 6 +-----
 Applications/DataExplorer/DataView/GMSHPrefsDialog.h       | 5 +----
 Applications/DataExplorer/DataView/GeoObjectListItem.h     | 5 +----
 .../DataExplorer/DataView/GeoOnMeshMappingDialog.h         | 5 +----
 Applications/DataExplorer/DataView/GeoTabWidget.h          | 5 +----
 Applications/DataExplorer/DataView/GeoTreeItem.h           | 5 +----
 Applications/DataExplorer/DataView/GeoTreeModel.h          | 5 +----
 Applications/DataExplorer/DataView/GeoTreeView.h           | 5 +----
 Applications/DataExplorer/DataView/LicenseDialog.h         | 5 +----
 Applications/DataExplorer/DataView/LineEditDialog.h        | 5 +----
 Applications/DataExplorer/DataView/LinearEditDialog.h      | 5 +----
 Applications/DataExplorer/DataView/MergeGeometriesDialog.h | 5 +----
 Applications/DataExplorer/DataView/MeshAnalysisDialog.h    | 5 +----
 .../DataExplorer/DataView/MeshElementRemovalDialog.h       | 5 +----
 Applications/DataExplorer/DataView/MeshLayerEditDialog.h   | 5 +----
 Applications/DataExplorer/DataView/MeshMapping2DDialog.h   | 5 +----
 .../DataExplorer/DataView/MeshQualitySelectionDialog.h     | 5 +----
 Applications/DataExplorer/DataView/MeshValueEditDialog.h   | 5 +----
 Applications/DataExplorer/DataView/ModelTreeItem.h         | 5 +----
 Applications/DataExplorer/DataView/ModellingTabWidget.h    | 5 +----
 Applications/DataExplorer/DataView/MshEditDialog.h         | 5 +----
 Applications/DataExplorer/DataView/MshItem.h               | 5 +----
 Applications/DataExplorer/DataView/MshModel.h              | 5 +----
 Applications/DataExplorer/DataView/MshTabWidget.h          | 5 +----
 Applications/DataExplorer/DataView/MshView.h               | 4 +---
 Applications/DataExplorer/DataView/NetCdfConfigureDialog.h | 6 +-----
 Applications/DataExplorer/DataView/SHPImportDialog.h       | 5 +----
 Applications/DataExplorer/DataView/SaveMeshDialog.h        | 5 +----
 Applications/DataExplorer/DataView/SelectMeshDialog.h      | 5 +----
 Applications/DataExplorer/DataView/SetNameDialog.h         | 5 +----
 Applications/DataExplorer/DataView/StationTabWidget.h      | 5 +----
 Applications/DataExplorer/DataView/StationTreeModel.h      | 5 +----
 Applications/DataExplorer/DataView/StationTreeView.h       | 5 +----
 Applications/DataExplorer/DataView/StratView/StratBar.h    | 5 +----
 Applications/DataExplorer/DataView/StratView/StratScene.h  | 5 +----
 Applications/DataExplorer/DataView/StratView/StratView.h   | 5 +----
 Applications/DataExplorer/DataView/StratView/StratWindow.h | 5 +----
 .../DataExplorer/DataView/SurfaceExtractionDialog.h        | 5 +----
 .../DataExplorer/VtkAct/VtkCustomInteractorStyle.h         | 6 +-----
 Applications/DataExplorer/VtkAct/VtkPickCallback.h         | 5 +----
 Applications/DataExplorer/VtkVis/MeshFromRasterDialog.h    | 5 +----
 Applications/DataExplorer/VtkVis/OGSFilterInfo.h           | 5 +----
 Applications/DataExplorer/VtkVis/QVtkDataSetMapper.h       | 5 +----
 Applications/DataExplorer/VtkVis/VisPrefsDialog.h          | 5 +----
 Applications/DataExplorer/VtkVis/VisualizationWidget.h     | 5 +----
 Applications/DataExplorer/VtkVis/VtkAddFilterDialog.h      | 5 +----
 Applications/DataExplorer/VtkVis/VtkAlgorithmProperties.h  | 5 +----
 .../DataExplorer/VtkVis/VtkAlgorithmPropertyCheckbox.h     | 5 +----
 .../DataExplorer/VtkVis/VtkAlgorithmPropertyLineEdit.h     | 5 +----
 .../DataExplorer/VtkVis/VtkAlgorithmPropertyVectorEdit.h   | 5 +----
 Applications/DataExplorer/VtkVis/VtkAppendArrayFilter.h    | 5 +----
 Applications/DataExplorer/VtkVis/VtkBGImageSource.h        | 5 +----
 Applications/DataExplorer/VtkVis/VtkColorByHeightFilter.h  | 5 +----
 Applications/DataExplorer/VtkVis/VtkColorLookupTable.h     | 5 +----
 .../DataExplorer/VtkVis/VtkCompositeColorByHeightFilter.h  | 5 +----
 .../VtkVis/VtkCompositeColormapToImageFilter.h             | 5 +----
 .../DataExplorer/VtkVis/VtkCompositeContourFilter.h        | 5 +----
 .../VtkVis/VtkCompositeElementSelectionFilter.h            | 5 +----
 Applications/DataExplorer/VtkVis/VtkCompositeFilter.h      | 5 +----
 .../DataExplorer/VtkVis/VtkCompositeGeoObjectFilter.h      | 5 +----
 .../VtkVis/VtkCompositeImageToCylindersFilter.h            | 5 +----
 .../DataExplorer/VtkVis/VtkCompositeLineToTubeFilter.h     | 5 +----
 .../DataExplorer/VtkVis/VtkCompositeNodeSelectionFilter.h  | 5 +----
 .../DataExplorer/VtkVis/VtkCompositePointToGlyphFilter.h   | 5 +----
 .../VtkVis/VtkCompositeTextureOnSurfaceFilter.h            | 5 +----
 .../DataExplorer/VtkVis/VtkCompositeThresholdFilter.h      | 5 +----
 Applications/DataExplorer/VtkVis/VtkConsoleOutputWindow.h  | 5 +----
 Applications/DataExplorer/VtkVis/VtkFilterFactory.h        | 5 +----
 Applications/DataExplorer/VtkVis/VtkGeoImageSource.h       | 5 +----
 .../DataExplorer/VtkVis/VtkImageDataToLinePolyDataFilter.h | 5 +----
 Applications/DataExplorer/VtkVis/VtkPointsSource.h         | 5 +----
 Applications/DataExplorer/VtkVis/VtkPolylinesSource.h      | 5 +----
 Applications/DataExplorer/VtkVis/VtkRaster.h               | 5 +----
 Applications/DataExplorer/VtkVis/VtkStationSource.h        | 5 +----
 Applications/DataExplorer/VtkVis/VtkSurfacesSource.h       | 5 +----
 .../DataExplorer/VtkVis/VtkTextureOnSurfaceFilter.h        | 5 +----
 Applications/DataExplorer/VtkVis/VtkVisHelper.h            | 5 +----
 Applications/DataExplorer/VtkVis/VtkVisImageItem.h         | 5 +----
 Applications/DataExplorer/VtkVis/VtkVisPipeline.h          | 5 +----
 Applications/DataExplorer/VtkVis/VtkVisPipelineItem.h      | 5 +----
 Applications/DataExplorer/VtkVis/VtkVisPipelineView.h      | 5 +----
 Applications/DataExplorer/VtkVis/VtkVisPointSetItem.h      | 5 +----
 Applications/DataExplorer/VtkVis/VtkVisTabWidget.h         | 5 +----
 Applications/DataExplorer/mainwindow.h                     | 5 +----
 Applications/DataHolderLib/Color.h                         | 5 +----
 Applications/DataHolderLib/ColorLookupTable.h              | 5 +----
 Applications/DataHolderLib/Project.h                       | 5 +----
 Applications/FileIO/AsciiRasterInterface.h                 | 5 +----
 Applications/FileIO/CsvInterface.h                         | 5 +----
 Applications/FileIO/FEFLOW/FEFLOWGeoInterface.h            | 5 +----
 Applications/FileIO/FEFLOW/FEFLOWMeshInterface.h           | 5 +----
 Applications/FileIO/GMSInterface.h                         | 5 +----
 Applications/FileIO/Gmsh/GMSHAdaptiveMeshDensity.h         | 5 +----
 Applications/FileIO/Gmsh/GMSHFixedMeshDensity.h            | 5 +----
 Applications/FileIO/Gmsh/GMSHInterface.h                   | 5 +----
 Applications/FileIO/Gmsh/GMSHLine.h                        | 5 +----
 Applications/FileIO/Gmsh/GMSHLineLoop.h                    | 5 +----
 Applications/FileIO/Gmsh/GMSHMeshDensityStrategy.h         | 5 +----
 Applications/FileIO/Gmsh/GMSHPoint.h                       | 5 +----
 Applications/FileIO/Gmsh/GMSHPolygonTree.h                 | 5 +----
 Applications/FileIO/PetrelInterface.h                      | 5 +----
 Applications/FileIO/SHPInterface.h                         | 5 +----
 Applications/FileIO/SWMM/SWMMInterface.h                   | 5 +----
 Applications/FileIO/TetGenInterface.h                      | 5 +----
 Applications/FileIO/XmlIO/Qt/XmlGspInterface.h             | 5 +----
 Applications/FileIO/XmlIO/Qt/XmlLutReader.h                | 5 +----
 Applications/FileIO/XmlIO/Qt/XmlNumInterface.h             | 5 +----
 .../PartitionMesh/NodeWiseMeshPartitioner.h                | 5 +----
 Applications/Utils/OGSFileConverter/FileListDialog.h       | 5 +----
 Applications/Utils/OGSFileConverter/OGSFileConverter.h     | 5 +----
 BaseLib/BuildInfo.h                                        | 5 +----
 BaseLib/CPUTime.h                                          | 6 +-----
 BaseLib/CodingTools.h                                      | 5 +----
 BaseLib/ConfigTree.h                                       | 7 +------
 BaseLib/ConfigTreeUtil.h                                   | 5 +----
 BaseLib/Counter.h                                          | 5 +----
 BaseLib/DateTools.h                                        | 5 +----
 BaseLib/DebugTools.h                                       | 6 +-----
 BaseLib/Error.h                                            | 5 +----
 BaseLib/FileFinder.h                                       | 5 +----
 BaseLib/FileTools.h                                        | 5 +----
 BaseLib/Functional.h                                       | 5 +----
 BaseLib/Histogram.h                                        | 5 +----
 BaseLib/IO/Writer.h                                        | 5 +----
 BaseLib/IO/XmlIO/Qt/XMLQtInterface.h                       | 5 +----
 BaseLib/IO/XmlIO/XMLInterface.h                            | 5 +----
 BaseLib/LogogCustomCout.h                                  | 5 +----
 BaseLib/LogogSimpleFormatter.h                             | 5 +----
 BaseLib/MemWatch.h                                         | 5 +----
 BaseLib/RunTime.h                                          | 5 +----
 BaseLib/StringTools.h                                      | 6 +-----
 BaseLib/Subdivision.h                                      | 5 +----
 BaseLib/TCLAPCustomOutput.h                                | 6 +-----
 BaseLib/TMPUtil.h                                          | 5 +----
 BaseLib/TemplateLogogFormatterSuppressedGCC.h              | 5 +----
 BaseLib/excludeObjectCopy.h                                | 6 +-----
 BaseLib/makeVectorUnique.h                                 | 4 +---
 BaseLib/quicksort.h                                        | 5 +----
 BaseLib/reorderVector.h                                    | 5 +----
 BaseLib/uniqueInsert.h                                     | 5 +----
 GeoLib/AABB.h                                              | 5 +----
 GeoLib/AnalyticalGeometry.h                                | 5 +----
 GeoLib/ClosestPair.h                                       | 5 +----
 GeoLib/DuplicateGeometry.h                                 | 5 +----
 GeoLib/EarClippingTriangulation.h                          | 5 +----
 GeoLib/GEOObjects.h                                        | 5 +----
 GeoLib/GeoObject.h                                         | 5 +----
 GeoLib/GeoType.h                                           | 5 +----
 GeoLib/Grid.h                                              | 5 +----
 GeoLib/IO/Legacy/OGSIOVer4.h                               | 5 +----
 GeoLib/IO/TINInterface.h                                   | 5 +----
 GeoLib/IO/XmlIO/Boost/BoostXmlGmlInterface.h               | 5 +----
 GeoLib/IO/XmlIO/Qt/XmlGmlInterface.h                       | 5 +----
 GeoLib/IO/XmlIO/Qt/XmlStnInterface.h                       | 5 +----
 GeoLib/IO/XmlIO/Rapid/RapidStnInterface.h                  | 5 +----
 GeoLib/IO/readGeometryFromFile.h                           | 5 +----
 GeoLib/IO/writeGeometryToFile.h                            | 5 +----
 GeoLib/LineSegment.h                                       | 4 +---
 GeoLib/MinimalBoundingSphere.h                             | 5 +----
 GeoLib/OctTree.h                                           | 5 +----
 GeoLib/Point.h                                             | 6 +-----
 GeoLib/PointVec.h                                          | 5 +----
 GeoLib/Polygon.h                                           | 5 +----
 GeoLib/PolygonWithSegmentMarker.h                          | 5 +----
 GeoLib/Polyline.h                                          | 5 +----
 GeoLib/PolylineVec.h                                       | 5 +----
 GeoLib/PolylineWithSegmentMarker.h                         | 5 +----
 GeoLib/QuadTree.h                                          | 5 +----
 GeoLib/Raster.h                                            | 5 +----
 GeoLib/SensorData.h                                        | 7 +------
 GeoLib/SimplePolygonTree.h                                 | 5 +----
 GeoLib/Station.h                                           | 6 +-----
 GeoLib/StationBorehole.h                                   | 6 +-----
 GeoLib/Surface.h                                           | 5 +----
 GeoLib/SurfaceGrid.h                                       | 5 +----
 GeoLib/SurfaceVec.h                                        | 6 +-----
 GeoLib/TemplateVec.h                                       | 5 +----
 GeoLib/Triangle.h                                          | 5 +----
 MaterialLib/Adsorption/Adsorption.h                        | 5 +----
 MaterialLib/Adsorption/Density100MPa.h                     | 4 +---
 MaterialLib/Adsorption/DensityConst.h                      | 4 +---
 MaterialLib/Adsorption/DensityCook.h                       | 4 +---
 MaterialLib/Adsorption/DensityDubinin.h                    | 4 +---
 MaterialLib/Adsorption/DensityHauer.h                      | 4 +---
 MaterialLib/Adsorption/DensityLegacy.h                     | 4 +---
 MaterialLib/Adsorption/DensityMette.h                      | 4 +---
 MaterialLib/Adsorption/DensityNunez.h                      | 4 +---
 MaterialLib/Adsorption/Reaction.h                          | 4 +---
 MaterialLib/Adsorption/ReactionCaOH2.h                     | 4 +---
 MaterialLib/Adsorption/ReactionInert.h                     | 4 +---
 MaterialLib/Adsorption/ReactionSinusoidal.h                | 4 +---
 MaterialLib/Fluid/ConstantFluidProperty.h                  | 4 +---
 MaterialLib/Fluid/Density/IdealGasLaw.h                    | 4 +---
 .../Fluid/Density/LinearTemperatureDependentDensity.h      | 5 +----
 MaterialLib/Fluid/Density/LiquidDensity.h                  | 5 +----
 MaterialLib/Fluid/Density/WaterDensityIAPWSIF97Region1.h   | 4 +---
 MaterialLib/Fluid/Density/createFluidDensityModel.h        | 4 +---
 MaterialLib/Fluid/FluidProperty.h                          | 5 +----
 MaterialLib/Fluid/FluidPropertyHeaders.h                   | 5 +----
 .../GibbsFreeEnergy/DimensionLessGibbsFreeEnergyRegion1.h  | 4 +---
 .../Fluid/Viscosity/LinearPressureDependentViscosity.h     | 4 +---
 .../Fluid/Viscosity/TemperatureDependentViscosity.h        | 5 +----
 MaterialLib/Fluid/Viscosity/VogelsLiquidDynamicViscosity.h | 4 +---
 MaterialLib/Fluid/Viscosity/WaterViscosityIAPWS.h          | 5 +----
 MaterialLib/Fluid/Viscosity/createViscosityModel.h         | 4 +---
 MaterialLib/FractureModels/CreateLinearElasticIsotropic.h  | 5 +----
 MaterialLib/FractureModels/CreateMohrCoulomb.h             | 5 +----
 MaterialLib/FractureModels/FractureIdentity2.h             | 5 +----
 MaterialLib/FractureModels/FractureModelBase.h             | 5 +----
 MaterialLib/FractureModels/LinearElasticIsotropic.h        | 5 +----
 MaterialLib/FractureModels/MohrCoulomb.h                   | 5 +----
 MaterialLib/PhysicalConstant.h                             | 4 +---
 .../PorousMedium/Permeability/createPermeabilityModel.h    | 5 +----
 MaterialLib/PorousMedium/Porosity/ConstantPorosity.h       | 5 +----
 MaterialLib/PorousMedium/Porosity/Porosity.h               | 5 +----
 MaterialLib/PorousMedium/Porosity/createPorosityModel.h    | 5 +----
 MaterialLib/PorousMedium/PorousPropertyHeaders.h           | 5 +----
 MaterialLib/PorousMedium/Storage/ConstantStorage.h         | 5 +----
 MaterialLib/PorousMedium/Storage/Storage.h                 | 5 +----
 MaterialLib/PorousMedium/Storage/createStorageModel.h      | 5 +----
 .../BrookCoreyCapillaryPressureSaturation.h                | 4 +---
 .../CapillaryPressure/CapillaryPressureSaturation.h        | 5 +----
 .../CapillaryPressure/CapillaryPressureSaturationCurve.h   | 5 +----
 .../CapillaryPressure/CreateCapillaryPressureModel.h       | 5 +----
 .../VanGenuchtenCapillaryPressureSaturation.h              | 4 +---
 .../RelativePermeability/CreateRelativePermeabilityModel.h | 5 +----
 .../RelativePermeability/NonWettingPhaseBrookCoreyOilGas.h | 5 +----
 .../RelativePermeability/NonWettingPhaseVanGenuchten.h     | 4 +---
 .../RelativePermeability/RelativePermeability.h            | 5 +----
 .../RelativePermeability/RelativePermeabilityCurve.h       | 4 +---
 .../RelativePermeability/WettingPhaseBrookCoreyOilGas.h    | 4 +---
 .../RelativePermeability/WettingPhaseVanGenuchten.h        | 4 +---
 MaterialLib/SolidModels/CreateEhlers.h                     | 5 +----
 MaterialLib/SolidModels/CreateLinearElasticIsotropic.h     | 5 +----
 MaterialLib/SolidModels/CreateLubby2.h                     | 5 +----
 MaterialLib/SolidModels/Ehlers-impl.h                      | 5 +----
 MaterialLib/SolidModels/Ehlers.h                           | 5 +----
 MaterialLib/SolidModels/KelvinVector.h                     | 5 +----
 MaterialLib/SolidModels/LinearElasticIsotropic.h           | 5 +----
 MaterialLib/SolidModels/Lubby2-impl.h                      | 5 +----
 MaterialLib/SolidModels/Lubby2.h                           | 5 +----
 MaterialLib/SolidModels/MechanicsBase.h                    | 5 +----
 .../TwoPhaseModels/CreateTwoPhaseFlowMaterialProperties.h  | 5 +----
 .../TwoPhaseModels/TwoPhaseFlowWithPPMaterialProperties.h  | 4 +---
 MathLib/ConstantFunction.h                                 | 5 +----
 MathLib/Curve/CreatePiecewiseLinearCurve.h                 | 5 +----
 MathLib/Curve/PiecewiseLinearMonotonicCurve.h              | 4 +---
 MathLib/GeometricBasics.h                                  | 5 +----
 MathLib/Integration/GaussLegendre.h                        | 7 +------
 MathLib/Integration/GaussLegendrePyramid.h                 | 5 +----
 MathLib/Integration/GaussLegendreTet.h                     | 5 +----
 MathLib/Integration/GaussLegendreTri.h                     | 5 +----
 MathLib/Integration/WeightedSum.h                          | 5 +----
 .../InterpolationAlgorithms/LinearIntervalInterpolation.h  | 5 +----
 .../InterpolationAlgorithms/PiecewiseLinearInterpolation.h | 5 +----
 MathLib/LinAlg/ApplyKnownSolution.h                        | 5 +----
 MathLib/LinAlg/Dense/DenseMatrix.h                         | 5 +----
 MathLib/LinAlg/Eigen/EigenLinearSolver.h                   | 6 +-----
 MathLib/LinAlg/Eigen/EigenMapTools.h                       | 5 +----
 MathLib/LinAlg/Eigen/EigenMatrix.h                         | 5 +----
 MathLib/LinAlg/Eigen/EigenOption.h                         | 4 +---
 MathLib/LinAlg/Eigen/EigenTools.h                          | 6 +-----
 MathLib/LinAlg/Eigen/EigenVector.h                         | 6 +-----
 MathLib/LinAlg/EigenLis/EigenLisLinearSolver.h             | 6 +-----
 MathLib/LinAlg/FinalizeMatrixAssembly.h                    | 5 +----
 MathLib/LinAlg/FinalizeVectorAssembly.h                    | 5 +----
 MathLib/LinAlg/GlobalMatrixVectorTypes.h                   | 5 +----
 MathLib/LinAlg/LinAlg.h                                    | 5 +----
 MathLib/LinAlg/LinAlgEnums.h                               | 5 +----
 MathLib/LinAlg/LinearSolverOptions.h                       | 5 +----
 MathLib/LinAlg/Lis/LisCheck.h                              | 6 +-----
 MathLib/LinAlg/Lis/LisLinearSolver.h                       | 6 +-----
 MathLib/LinAlg/Lis/LisMatrix.h                             | 5 +----
 MathLib/LinAlg/Lis/LisOption.h                             | 4 +---
 MathLib/LinAlg/Lis/LisVector.h                             | 5 +----
 MathLib/LinAlg/MatrixSpecifications.h                      | 6 +-----
 MathLib/LinAlg/MatrixVectorTraits.h                        | 5 +----
 MathLib/LinAlg/PETSc/PETScLinearSolver.h                   | 5 +----
 MathLib/LinAlg/PETSc/PETScMatrix.h                         | 5 +----
 MathLib/LinAlg/PETSc/PETScMatrixOption.h                   | 5 +----
 MathLib/LinAlg/PETSc/PETScTools.h                          | 6 +-----
 MathLib/LinAlg/PETSc/PETScVector.h                         | 4 +---
 MathLib/LinAlg/RowColumnIndices.h                          | 5 +----
 MathLib/LinAlg/SetMatrixSparsity.h                         | 5 +----
 MathLib/LinAlg/Solvers/GaussAlgorithm.h                    | 5 +----
 MathLib/LinAlg/Solvers/TriangularSolve.h                   | 5 +----
 MathLib/LinAlg/SparsityPattern.h                           | 5 +----
 MathLib/LinAlg/UnifiedMatrixSetters.h                      | 5 +----
 MathLib/LinearFunction.h                                   | 5 +----
 MathLib/MathTools.h                                        | 5 +----
 MathLib/Nonlinear/Root1D.h                                 | 5 +----
 MathLib/ODE/CVodeSolver.h                                  | 5 +----
 MathLib/ODE/ConcreteODESolver.h                            | 5 +----
 MathLib/ODE/FunctionHandles.h                              | 5 +----
 MathLib/ODE/ODESolver.h                                    | 5 +----
 MathLib/ODE/ODESolverBuilder.h                             | 5 +----
 MathLib/ODE/ODESolverTypes.h                               | 5 +----
 MathLib/Point3d.h                                          | 6 +-----
 MathLib/Point3dWithID.h                                    | 6 +-----
 MathLib/TemplatePoint.h                                    | 5 +----
 MathLib/TemplateWeightedPoint.h                            | 6 +-----
 MathLib/Vector3.h                                          | 5 +----
 MeshGeoToolsLib/AppendLinesAlongPolyline.h                 | 5 +----
 MeshGeoToolsLib/BoundaryElementsAlongPolyline.h            | 5 +----
 MeshGeoToolsLib/BoundaryElementsAtPoint.h                  | 5 +----
 MeshGeoToolsLib/BoundaryElementsOnSurface.h                | 5 +----
 MeshGeoToolsLib/BoundaryElementsSearcher.h                 | 5 +----
 MeshGeoToolsLib/GeoMapper.h                                | 5 +----
 MeshGeoToolsLib/HeuristicSearchLength.h                    | 6 +-----
 MeshGeoToolsLib/MeshNodeSearcher.h                         | 5 +----
 MeshGeoToolsLib/MeshNodesAlongPolyline.h                   | 5 +----
 MeshGeoToolsLib/MeshNodesAlongSurface.h                    | 5 +----
 MeshGeoToolsLib/MeshNodesOnPoint.h                         | 5 +----
 MeshGeoToolsLib/SearchLength.h                             | 6 +-----
 MeshLib/CoordinateSystem.h                                 | 5 +----
 MeshLib/ElementCoordinatesMappingLocal.h                   | 5 +----
 MeshLib/ElementStatus.h                                    | 5 +----
 MeshLib/Elements/CellRule.h                                | 6 +-----
 MeshLib/Elements/EdgeReturn.h                              | 7 +------
 MeshLib/Elements/EdgeRule.h                                | 6 +-----
 MeshLib/Elements/Element.h                                 | 6 +-----
 MeshLib/Elements/ElementErrorCode.h                        | 6 +-----
 MeshLib/Elements/Elements.h                                | 5 +----
 MeshLib/Elements/FaceRule.h                                | 6 +-----
 MeshLib/Elements/Hex.h                                     | 5 +----
 MeshLib/Elements/HexRule20.h                               | 6 +-----
 MeshLib/Elements/HexRule8.h                                | 6 +-----
 MeshLib/Elements/Line.h                                    | 6 +-----
 MeshLib/Elements/LineRule2.h                               | 6 +-----
 MeshLib/Elements/LineRule3.h                               | 6 +-----
 MeshLib/Elements/Point.h                                   | 5 +----
 MeshLib/Elements/PointRule1.h                              | 6 +-----
 MeshLib/Elements/Prism.h                                   | 5 +----
 MeshLib/Elements/PrismRule15.h                             | 6 +-----
 MeshLib/Elements/PrismRule6.h                              | 6 +-----
 MeshLib/Elements/Pyramid.h                                 | 5 +----
 MeshLib/Elements/PyramidRule13.h                           | 6 +-----
 MeshLib/Elements/PyramidRule5.h                            | 6 +-----
 MeshLib/Elements/Quad.h                                    | 5 +----
 MeshLib/Elements/QuadRule4.h                               | 6 +-----
 MeshLib/Elements/QuadRule8.h                               | 6 +-----
 MeshLib/Elements/QuadRule9.h                               | 6 +-----
 MeshLib/Elements/TemplateElement.h                         | 6 +-----
 MeshLib/Elements/Tet.h                                     | 5 +----
 MeshLib/Elements/TetRule10.h                               | 6 +-----
 MeshLib/Elements/TetRule4.h                                | 6 +-----
 MeshLib/Elements/Tri.h                                     | 5 +----
 MeshLib/Elements/TriRule3.h                                | 6 +-----
 MeshLib/Elements/TriRule6.h                                | 6 +-----
 MeshLib/Elements/Utils.h                                   | 5 +----
 MeshLib/Elements/VertexRule.h                              | 6 +-----
 MeshLib/IO/Legacy/MeshIO.h                                 | 6 +-----
 MeshLib/IO/MPI_IO/NodePartitionedMeshReader.h              | 5 +----
 MeshLib/IO/VtkIO/PVDFile.h                                 | 5 +----
 MeshLib/IO/VtkIO/VtuInterface.h                            | 5 +----
 MeshLib/IO/readMeshFromFile.h                              | 4 +---
 MeshLib/IO/writeMeshToFile.h                               | 5 +----
 MeshLib/Location.h                                         | 5 +----
 MeshLib/Mesh.h                                             | 6 +-----
 MeshLib/MeshEditing/AddLayerToMesh.h                       | 5 +----
 MeshLib/MeshEditing/ConvertToLinearMesh.h                  | 5 +----
 MeshLib/MeshEditing/DuplicateMeshComponents.h              | 5 +----
 MeshLib/MeshEditing/ElementValueModification.h             | 5 +----
 MeshLib/MeshEditing/FlipElements.h                         | 5 +----
 MeshLib/MeshEditing/Mesh2MeshPropertyInterpolation.h       | 5 +----
 MeshLib/MeshEditing/MeshRevision.h                         | 5 +----
 MeshLib/MeshEditing/RemoveMeshComponents.h                 | 5 +----
 MeshLib/MeshEditing/moveMeshNodes.h                        | 5 +----
 MeshLib/MeshEditing/projectMeshOntoPlane.h                 | 5 +----
 MeshLib/MeshEnums.h                                        | 5 +----
 MeshLib/MeshGenerators/LayeredMeshGenerator.h              | 5 +----
 MeshLib/MeshGenerators/LayeredVolume.h                     | 5 +----
 MeshLib/MeshGenerators/MeshGenerator.h                     | 5 +----
 MeshLib/MeshGenerators/MeshLayerMapper.h                   | 5 +----
 MeshLib/MeshGenerators/RasterToMesh.h                      | 5 +----
 MeshLib/MeshGenerators/VtkMeshConverter.h                  | 5 +----
 MeshLib/MeshInformation.h                                  | 5 +----
 MeshLib/MeshQuality/AngleSkewMetric.h                      | 5 +----
 MeshLib/MeshQuality/EdgeRatioMetric.h                      | 5 +----
 MeshLib/MeshQuality/ElementQualityInterface.h              | 5 +----
 MeshLib/MeshQuality/ElementQualityMetric.h                 | 5 +----
 MeshLib/MeshQuality/ElementSizeMetric.h                    | 5 +----
 MeshLib/MeshQuality/MeshValidation.h                       | 5 +----
 MeshLib/MeshQuality/RadiusEdgeRatioMetric.h                | 5 +----
 MeshLib/MeshQuality/SizeDifferenceMetric.h                 | 5 +----
 MeshLib/MeshSearch/ElementSearch.h                         | 5 +----
 MeshLib/MeshSearch/MeshElementGrid.h                       | 5 +----
 MeshLib/MeshSearch/NodeSearch.h                            | 5 +----
 MeshLib/MeshSubset.h                                       | 5 +----
 MeshLib/MeshSubsets.h                                      | 5 +----
 MeshLib/MeshSurfaceExtraction.h                            | 5 +----
 MeshLib/Node.h                                             | 6 +-----
 MeshLib/NodeAdjacencyTable.h                               | 5 +----
 MeshLib/NodePartitionedMesh.h                              | 5 +----
 MeshLib/Properties.h                                       | 6 +-----
 MeshLib/PropertyVector.h                                   | 5 +----
 MeshLib/Vtk/VtkMappedMesh.h                                | 5 +----
 MeshLib/Vtk/VtkMappedMeshSource.h                          | 5 +----
 MeshLib/Vtk/VtkMappedPropertyVectorTemplate.h              | 5 +----
 MeshLib/Vtk/VtkMeshNodalCoordinatesTemplate.h              | 5 +----
 MeshLib/VtkOGSEnum.h                                       | 5 +----
 MeshLib/convertMeshToGeo.h                                 | 5 +----
 NumLib/Assembler/SerialExecutor.h                          | 5 +----
 NumLib/DOF/ComponentGlobalIndexDict.h                      | 5 +----
 NumLib/DOF/ComputeSparsityPattern.h                        | 6 +-----
 NumLib/DOF/DOFTableUtil.h                                  | 5 +----
 NumLib/DOF/GlobalMatrixProviders.h                         | 5 +----
 NumLib/DOF/LocalToGlobalIndexMap.h                         | 5 +----
 NumLib/DOF/MatrixProviderUser.h                            | 5 +----
 NumLib/DOF/MeshComponentMap.h                              | 5 +----
 NumLib/DOF/SimpleMatrixVectorProvider.h                    | 5 +----
 NumLib/Distribution/Distribution.h                         | 6 +-----
 NumLib/Extrapolation/ExtrapolatableElement.h               | 5 +----
 NumLib/Extrapolation/ExtrapolatableElementCollection.h     | 5 +----
 NumLib/Extrapolation/Extrapolator.h                        | 5 +----
 NumLib/Extrapolation/LocalLinearLeastSquaresExtrapolator.h | 5 +----
 NumLib/Fem/CoordinatesMapping/NaturalCoordinatesMapping.h  | 7 +------
 NumLib/Fem/CoordinatesMapping/ShapeMatrices.h              | 5 +----
 NumLib/Fem/FiniteElement/C0IsoparametricElements.h         | 6 +-----
 NumLib/Fem/FiniteElement/LowerDimShapeTable.h              | 5 +----
 NumLib/Fem/FiniteElement/TemplateIsoparametric.h           | 7 +------
 NumLib/Fem/Integration/GaussIntegrationPolicy.h            | 5 +----
 NumLib/Fem/Integration/IntegrationGaussPrism.h             | 5 +----
 NumLib/Fem/Integration/IntegrationGaussPyramid.h           | 5 +----
 NumLib/Fem/Integration/IntegrationGaussRegular.h           | 5 +----
 NumLib/Fem/Integration/IntegrationGaussTet.h               | 5 +----
 NumLib/Fem/Integration/IntegrationGaussTri.h               | 5 +----
 NumLib/Fem/Integration/IntegrationPoint.h                  | 5 +----
 NumLib/Fem/ShapeFunction/ShapeHex20.h                      | 5 +----
 NumLib/Fem/ShapeFunction/ShapeHex8.h                       | 5 +----
 NumLib/Fem/ShapeFunction/ShapeLine2.h                      | 5 +----
 NumLib/Fem/ShapeFunction/ShapeLine3.h                      | 5 +----
 NumLib/Fem/ShapeFunction/ShapePoint1.h                     | 5 +----
 NumLib/Fem/ShapeFunction/ShapePrism15.h                    | 5 +----
 NumLib/Fem/ShapeFunction/ShapePrism6.h                     | 5 +----
 NumLib/Fem/ShapeFunction/ShapePyra13.h                     | 5 +----
 NumLib/Fem/ShapeFunction/ShapePyra5.h                      | 5 +----
 NumLib/Fem/ShapeFunction/ShapeQuad4.h                      | 5 +----
 NumLib/Fem/ShapeFunction/ShapeQuad8.h                      | 5 +----
 NumLib/Fem/ShapeFunction/ShapeQuad9.h                      | 5 +----
 NumLib/Fem/ShapeFunction/ShapeTet10.h                      | 5 +----
 NumLib/Fem/ShapeFunction/ShapeTet4.h                       | 5 +----
 NumLib/Fem/ShapeFunction/ShapeTri3.h                       | 5 +----
 NumLib/Fem/ShapeFunction/ShapeTri6.h                       | 5 +----
 NumLib/Fem/ShapeMatrixPolicy.h                             | 5 +----
 NumLib/Function/ISpatialFunction.h                         | 6 +-----
 NumLib/Function/Interpolation.h                            | 5 +----
 NumLib/Function/LinearInterpolationAlongPolyline.h         | 6 +-----
 NumLib/Function/LinearInterpolationOnSurface.h             | 6 +-----
 NumLib/Function/SpatialFunctionLinear.h                    | 5 +----
 NumLib/Function/TemplateSpatialFunction.h                  | 5 +----
 NumLib/IndexValueVector.h                                  | 5 +----
 NumLib/NamedFunction.h                                     | 5 +----
 NumLib/NamedFunctionCaller.h                               | 7 +------
 NumLib/NamedFunctionProvider.h                             | 5 +----
 NumLib/NewtonRaphson.h                                     | 5 +----
 NumLib/NumericsConfig.h                                    | 7 +------
 NumLib/ODESolver/ConvergenceCriterion.h                    | 5 +----
 NumLib/ODESolver/ConvergenceCriterionDeltaX.h              | 5 +----
 NumLib/ODESolver/ConvergenceCriterionPerComponent.h        | 5 +----
 NumLib/ODESolver/ConvergenceCriterionPerComponentDeltaX.h  | 5 +----
 .../ODESolver/ConvergenceCriterionPerComponentResidual.h   | 5 +----
 NumLib/ODESolver/ConvergenceCriterionResidual.h            | 5 +----
 NumLib/ODESolver/EquationSystem.h                          | 5 +----
 NumLib/ODESolver/MatrixTranslator.h                        | 5 +----
 NumLib/ODESolver/NonlinearSolver.h                         | 5 +----
 NumLib/ODESolver/NonlinearSystem.h                         | 5 +----
 NumLib/ODESolver/ODESystem.h                               | 5 +----
 NumLib/ODESolver/TimeDiscretization.h                      | 5 +----
 NumLib/ODESolver/TimeDiscretizationBuilder.h               | 5 +----
 NumLib/ODESolver/TimeDiscretizedODESystem.h                | 5 +----
 NumLib/ODESolver/TimeLoopSingleODE.h                       | 5 +----
 NumLib/ODESolver/Types.h                                   | 5 +----
 NumLib/TimeStepping/Algorithms/FixedTimeStepping.h         | 5 +----
 NumLib/TimeStepping/Algorithms/ITimeStepAlgorithm.h        | 5 +----
 .../Algorithms/IterationNumberBasedAdaptiveTimeStepping.h  | 5 +----
 NumLib/TimeStepping/TimeStep.h                             | 5 +----
 ProcessLib/AbstractJacobianAssembler.h                     | 5 +----
 ProcessLib/AnalyticalJacobianAssembler.h                   | 5 +----
 ProcessLib/BoundaryCondition/BoundaryCondition.h           | 5 +----
 ProcessLib/BoundaryCondition/BoundaryConditionCollection.h | 5 +----
 ProcessLib/BoundaryCondition/BoundaryConditionConfig.h     | 5 +----
 ProcessLib/BoundaryCondition/DirichletBoundaryCondition.h  | 5 +----
 .../BoundaryCondition/GenericNaturalBoundaryCondition.h    | 5 +----
 .../GenericNaturalBoundaryConditionLocalAssembler.h        | 5 +----
 ProcessLib/BoundaryCondition/NeumannBoundaryCondition.h    | 5 +----
 .../NeumannBoundaryConditionLocalAssembler.h               | 5 +----
 ProcessLib/BoundaryCondition/RobinBoundaryCondition.h      | 5 +----
 .../RobinBoundaryConditionLocalAssembler.h                 | 5 +----
 ProcessLib/CachedSecondaryVariable.h                       | 5 +----
 ProcessLib/CalculateSurfaceFlux/CalculateSurfaceFlux.h     | 5 +----
 .../CalculateSurfaceFluxLocalAssembler.h                   | 5 +----
 ProcessLib/CalculateSurfaceFlux/MapBulkElementPoint.h      | 4 +---
 ProcessLib/CentralDifferencesJacobianAssembler.h           | 5 +----
 ProcessLib/CreateJacobianAssembler.h                       | 5 +----
 ProcessLib/Deformation/BMatrixPolicy.h                     | 5 +----
 ProcessLib/Deformation/LinearBMatrix.h                     | 5 +----
 ProcessLib/ExtrapolatorData.h                              | 6 +-----
 ProcessLib/GlobalVectorFromNamedFunction.h                 | 5 +----
 ProcessLib/GroundwaterFlow/CreateGroundwaterFlowProcess.h  | 5 +----
 ProcessLib/GroundwaterFlow/GroundwaterFlowFEM.h            | 5 +----
 ProcessLib/GroundwaterFlow/GroundwaterFlowProcess.h        | 5 +----
 ProcessLib/GroundwaterFlow/GroundwaterFlowProcessData.h    | 5 +----
 ProcessLib/HT/CreateHTProcess.h                            | 5 +----
 ProcessLib/HT/HTFEM.h                                      | 5 +----
 ProcessLib/HT/HTProcess.h                                  | 5 +----
 ProcessLib/HT/HTProcessData.h                              | 5 +----
 ProcessLib/HeatConduction/CreateHeatConductionProcess.h    | 5 +----
 ProcessLib/HeatConduction/HeatConductionFEM.h              | 5 +----
 ProcessLib/HeatConduction/HeatConductionProcess.h          | 5 +----
 ProcessLib/HeatConduction/HeatConductionProcessData.h      | 5 +----
 ProcessLib/HydroMechanics/CreateHydroMechanicsProcess.h    | 5 +----
 ProcessLib/HydroMechanics/CreateLocalAssemblers.h          | 5 +----
 ProcessLib/HydroMechanics/HydroMechanicsFEM.h              | 5 +----
 ProcessLib/HydroMechanics/HydroMechanicsProcess-fwd.h      | 5 +----
 ProcessLib/HydroMechanics/HydroMechanicsProcess.h          | 5 +----
 ProcessLib/HydroMechanics/HydroMechanicsProcessData.h      | 5 +----
 ProcessLib/HydroMechanics/LocalDataInitializer.h           | 5 +----
 .../LIE/BoundaryCondition/BoundaryConditionBuilder.h       | 5 +----
 .../GenericNaturalBoundaryCondition-impl.h                 | 5 +----
 .../BoundaryCondition/GenericNaturalBoundaryCondition.h    | 5 +----
 .../LIE/BoundaryCondition/NeumannBoundaryCondition.h       | 5 +----
 .../NeumannBoundaryConditionLocalAssembler.h               | 5 +----
 ProcessLib/LIE/Common/FractureProperty.h                   | 5 +----
 ProcessLib/LIE/Common/HMatrixUtils.h                       | 5 +----
 ProcessLib/LIE/Common/LevelSetFunction.h                   | 5 +----
 ProcessLib/LIE/Common/MeshUtils.h                          | 5 +----
 ProcessLib/LIE/Common/PostUtils.h                          | 5 +----
 ProcessLib/LIE/Common/Utils.h                              | 5 +----
 .../LIE/HydroMechanics/CreateHydroMechanicsProcess.h       | 5 +----
 ProcessLib/LIE/HydroMechanics/HydroMechanicsProcess-fwd.h  | 5 +----
 ProcessLib/LIE/HydroMechanics/HydroMechanicsProcess.h      | 5 +----
 ProcessLib/LIE/HydroMechanics/HydroMechanicsProcessData.h  | 5 +----
 .../HydroMechanics/LocalAssembler/CreateLocalAssemblers.h  | 5 +----
 .../HydroMechanicsLocalAssemblerFracture-impl.h            | 5 +----
 .../LocalAssembler/HydroMechanicsLocalAssemblerFracture.h  | 5 +----
 .../LocalAssembler/HydroMechanicsLocalAssemblerInterface.h | 5 +----
 .../HydroMechanicsLocalAssemblerMatrix-impl.h              | 5 +----
 .../LocalAssembler/HydroMechanicsLocalAssemblerMatrix.h    | 5 +----
 .../HydroMechanicsLocalAssemblerMatrixNearFracture-impl.h  | 5 +----
 .../HydroMechanicsLocalAssemblerMatrixNearFracture.h       | 5 +----
 .../LocalAssembler/IntegrationPointDataFracture.h          | 5 +----
 .../LocalAssembler/IntegrationPointDataMatrix.h            | 5 +----
 .../HydroMechanics/LocalAssembler/LocalDataInitializer.h   | 5 +----
 .../LIE/SmallDeformation/CreateSmallDeformationProcess.h   | 5 +----
 .../LocalAssembler/CreateLocalAssemblers.h                 | 5 +----
 .../LocalAssembler/IntegrationPointDataFracture.h          | 5 +----
 .../LocalAssembler/IntegrationPointDataMatrix.h            | 5 +----
 .../LocalAssembler/LocalAssemblerDataFracture.h            | 5 +----
 .../LocalAssembler/LocalAssemblerDataMatrix.h              | 5 +----
 .../LocalAssembler/LocalAssemblerDataMatrixNearFracture.h  | 5 +----
 .../SmallDeformation/LocalAssembler/LocalDataInitializer.h | 5 +----
 .../LIE/SmallDeformation/LocalAssembler/SecondaryData.h    | 5 +----
 .../SmallDeformationLocalAssemblerFracture-impl.h          | 5 +----
 .../SmallDeformationLocalAssemblerFracture.h               | 5 +----
 .../SmallDeformationLocalAssemblerInterface.h              | 5 +----
 .../SmallDeformationLocalAssemblerMatrix-impl.h            | 5 +----
 .../LocalAssembler/SmallDeformationLocalAssemblerMatrix.h  | 5 +----
 ...SmallDeformationLocalAssemblerMatrixNearFracture-impl.h | 5 +----
 .../SmallDeformationLocalAssemblerMatrixNearFracture.h     | 5 +----
 .../LIE/SmallDeformation/SmallDeformationProcess-fwd.h     | 5 +----
 ProcessLib/LIE/SmallDeformation/SmallDeformationProcess.h  | 5 +----
 .../LIE/SmallDeformation/SmallDeformationProcessData.h     | 5 +----
 ProcessLib/LiquidFlow/CreateLiquidFlowProcess.h            | 5 +----
 ProcessLib/LiquidFlow/LiquidFlowLocalAssembler-impl.h      | 5 +----
 ProcessLib/LiquidFlow/LiquidFlowLocalAssembler.h           | 5 +----
 ProcessLib/LiquidFlow/LiquidFlowMaterialProperties.h       | 4 +---
 ProcessLib/LiquidFlow/LiquidFlowProcess.h                  | 5 +----
 ProcessLib/LocalAssemblerInterface.h                       | 5 +----
 ProcessLib/LocalAssemblerTraits.h                          | 5 +----
 ProcessLib/Output.h                                        | 5 +----
 ProcessLib/Parameter/ConstantParameter.h                   | 5 +----
 ProcessLib/Parameter/CurveScaledParameter.h                | 5 +----
 ProcessLib/Parameter/GroupBasedParameter.h                 | 5 +----
 ProcessLib/Parameter/MeshElementParameter.h                | 5 +----
 ProcessLib/Parameter/MeshNodeParameter.h                   | 5 +----
 ProcessLib/Parameter/Parameter.h                           | 5 +----
 ProcessLib/Parameter/SpatialPosition.h                     | 5 +----
 ProcessLib/Process.h                                       | 5 +----
 ProcessLib/ProcessOutput.h                                 | 6 +-----
 ProcessLib/ProcessVariable.h                               | 5 +----
 ProcessLib/RichardsFlow/CreateRichardsFlowProcess.h        | 5 +----
 ProcessLib/RichardsFlow/RichardsFlowFEM.h                  | 5 +----
 ProcessLib/RichardsFlow/RichardsFlowProcess.h              | 5 +----
 ProcessLib/RichardsFlow/RichardsFlowProcessData.h          | 5 +----
 ProcessLib/SecondaryVariable.h                             | 5 +----
 ProcessLib/SecondaryVariableContext.h                      | 5 +----
 ProcessLib/SmallDeformation/CreateLocalAssemblers.h        | 5 +----
 .../SmallDeformation/CreateSmallDeformationProcess.h       | 5 +----
 ProcessLib/SmallDeformation/LocalDataInitializer.h         | 5 +----
 ProcessLib/SmallDeformation/SmallDeformationFEM.h          | 5 +----
 ProcessLib/SmallDeformation/SmallDeformationProcess-fwd.h  | 5 +----
 ProcessLib/SmallDeformation/SmallDeformationProcess.h      | 5 +----
 ProcessLib/SmallDeformation/SmallDeformationProcessData.h  | 5 +----
 ProcessLib/TES/CreateTESProcess.h                          | 5 +----
 ProcessLib/TES/TESAssemblyParams.h                         | 5 +----
 ProcessLib/TES/TESLocalAssembler-impl.h                    | 5 +----
 ProcessLib/TES/TESLocalAssembler.h                         | 5 +----
 ProcessLib/TES/TESLocalAssemblerData.h                     | 4 +---
 ProcessLib/TES/TESLocalAssemblerInner-fwd.h                | 5 +----
 ProcessLib/TES/TESLocalAssemblerInner-impl.h               | 5 +----
 ProcessLib/TES/TESLocalAssemblerInner.h                    | 5 +----
 ProcessLib/TES/TESOGS5MaterialModels.h                     | 5 +----
 ProcessLib/TES/TESProcess.h                                | 5 +----
 ProcessLib/TES/TESReactionAdaptor.h                        | 4 +---
 .../TwoPhaseFlowWithPP/CreateTwoPhaseFlowWithPPProcess.h   | 5 +----
 .../TwoPhaseFlowWithPPLocalAssembler-impl.h                | 5 +----
 .../TwoPhaseFlowWithPP/TwoPhaseFlowWithPPLocalAssembler.h  | 5 +----
 ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPProcess.h  | 5 +----
 .../TwoPhaseFlowWithPP/TwoPhaseFlowWithPPProcessData.h     | 5 +----
 ProcessLib/UncoupledProcessesTimeLoop.h                    | 5 +----
 ProcessLib/Utils/CreateLocalAssemblers.h                   | 5 +----
 ProcessLib/Utils/InitShapeMatrices.h                       | 6 +-----
 ProcessLib/Utils/LocalDataInitializer.h                    | 5 +----
 ProcessLib/Utils/ParseSecondaryVariables.h                 | 5 +----
 ProcessLib/Utils/ProcessUtils.h                            | 5 +----
 ProcessLib/VariableTransformation.h                        | 4 +---
 ProcessLib/VectorMatrixAssembler.h                         | 5 +----
 Tests/GeoLib/AutoCheckGenerators.h                         | 5 +----
 Tests/InstanceCounter.h                                    | 5 +----
 Tests/MathLib/AutoCheckTools.h                             | 4 +---
 Tests/NumLib/CoordinatesMappingTestData/TestHex8.h         | 7 +------
 Tests/NumLib/CoordinatesMappingTestData/TestLine2.h        | 5 +----
 Tests/NumLib/CoordinatesMappingTestData/TestLine3.h        | 5 +----
 Tests/NumLib/CoordinatesMappingTestData/TestQuad4.h        | 6 +-----
 Tests/NumLib/CoordinatesMappingTestData/TestTri3.h         | 5 +----
 Tests/NumLib/FeTestData/MatrixTools.h                      | 6 +-----
 Tests/NumLib/FeTestData/TestFeHEX8.h                       | 6 +-----
 Tests/NumLib/FeTestData/TestFeLINE2.h                      | 6 +-----
 Tests/NumLib/FeTestData/TestFeLINE2Y.h                     | 6 +-----
 Tests/NumLib/FeTestData/TestFeLINE3.h                      | 6 +-----
 Tests/NumLib/FeTestData/TestFePRISM6.h                     | 6 +-----
 Tests/NumLib/FeTestData/TestFePYRA5.h                      | 6 +-----
 Tests/NumLib/FeTestData/TestFeQUAD4.h                      | 6 +-----
 Tests/NumLib/FeTestData/TestFeTET4.h                       | 6 +-----
 Tests/NumLib/FeTestData/TestFeTRI3.h                       | 6 +-----
 Tests/NumLib/ODEs.h                                        | 5 +----
 Tests/NumLib/SteadyDiffusion2DExample1.h                   | 6 +-----
 Tests/NumLib/TimeSteppingTestingTools.h                    | 5 +----
 Tests/TestTools.h                                          | 5 +----
 676 files changed, 676 insertions(+), 2759 deletions(-)

diff --git a/Applications/ApplicationsLib/LinearSolverLibrarySetup.h b/Applications/ApplicationsLib/LinearSolverLibrarySetup.h
index 22049f47730..dea388d1082 100644
--- a/Applications/ApplicationsLib/LinearSolverLibrarySetup.h
+++ b/Applications/ApplicationsLib/LinearSolverLibrarySetup.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef APPLICATIONSLIB_LINEARSOLVERLIBRARYSETUP_H_
-#define APPLICATIONSLIB_LINEARSOLVERLIBRARYSETUP_H_
+#pragma once
 
 /// The LinearSolverLibrarySetup takes care of proper initialization and
 /// shutting down of an external linear solver library. The concrete
@@ -74,6 +73,3 @@ struct LinearSolverLibrarySetup final
 };
 }    // ApplicationsLib
 #endif
-
-
-#endif  // APPLICATIONSLIB_LINEARSOLVERLIBRARYSETUP_H_
diff --git a/Applications/ApplicationsLib/LogogSetup.h b/Applications/ApplicationsLib/LogogSetup.h
index e760b207709..9862f4a290b 100644
--- a/Applications/ApplicationsLib/LogogSetup.h
+++ b/Applications/ApplicationsLib/LogogSetup.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef APPLICATIONSLIB_LOGOGSETUP_H_
-#define APPLICATIONSLIB_LOGOGSETUP_H_
+#pragma once
 
 #include <map>
 #include <memory>
@@ -83,5 +82,3 @@ private:
 };
 
 }    // ApplicationsLib
-
-#endif  // APPLICATIONSLIB_LOGOGSETUP_H_
diff --git a/Applications/ApplicationsLib/ProjectData.h b/Applications/ApplicationsLib/ProjectData.h
index 5cbe24c7ae5..107de6b9512 100644
--- a/Applications/ApplicationsLib/ProjectData.h
+++ b/Applications/ApplicationsLib/ProjectData.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef PROJECTDATA_H_
-#define PROJECTDATA_H_
+#pragma once
 
 #include <boost/optional/optional.hpp>
 #include <map>
@@ -171,5 +170,3 @@ private:
              std::unique_ptr<MathLib::PiecewiseLinearInterpolation>>
         _curves;
 };
-
-#endif  // PROJECTDATA_H_
diff --git a/Applications/DataExplorer/Base/CheckboxDelegate.h b/Applications/DataExplorer/Base/CheckboxDelegate.h
index b8757197f9f..0e82581b7c8 100644
--- a/Applications/DataExplorer/Base/CheckboxDelegate.h
+++ b/Applications/DataExplorer/Base/CheckboxDelegate.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef CHECKBOXDELEGATE_H
-#define CHECKBOXDELEGATE_H
+#pragma once
 
 #include <QItemDelegate>
 
@@ -47,5 +46,3 @@ public:
 private:
     QRect checkboxRect(const QStyleOptionViewItem& viewItemStyleOptions) const;
 };
-
-#endif // CHECKBOXDELEGATE_H
diff --git a/Applications/DataExplorer/Base/ColorPickerPushButton.h b/Applications/DataExplorer/Base/ColorPickerPushButton.h
index e7706f6f448..5596d767fc7 100644
--- a/Applications/DataExplorer/Base/ColorPickerPushButton.h
+++ b/Applications/DataExplorer/Base/ColorPickerPushButton.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef COLORPICKERPUSHBUTTON_H
-#define COLORPICKERPUSHBUTTON_H
+#pragma once
 
 // ** INCLUDES **
 #include <QPushButton>
@@ -51,5 +50,3 @@ signals:
     /// Is emitted when a color was picked from the dialog.
     void colorPicked(QColor);
 };
-
-#endif // COLORPICKERPUSHBUTTON_H
diff --git a/Applications/DataExplorer/Base/ImportFileTypes.h b/Applications/DataExplorer/Base/ImportFileTypes.h
index 489402ec4b3..86369b9a60b 100644
--- a/Applications/DataExplorer/Base/ImportFileTypes.h
+++ b/Applications/DataExplorer/Base/ImportFileTypes.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef IMPORTFILETYPES_H
-#define IMPORTFILETYPES_H
+#pragma once
 
 #include <string>
 
@@ -91,5 +90,3 @@ public:
 }
 
 };
-
-#endif //IMPORTFILETYPES_H
diff --git a/Applications/DataExplorer/Base/LastSavedFileDirectory.h b/Applications/DataExplorer/Base/LastSavedFileDirectory.h
index aa93c9d1562..aa1027c887a 100644
--- a/Applications/DataExplorer/Base/LastSavedFileDirectory.h
+++ b/Applications/DataExplorer/Base/LastSavedFileDirectory.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef LASTUSEDSAVEDFILEDIRECTORY_H
-#define LASTUSEDSAVEDFILEDIRECTORY_H
+#pragma once
 
 #include <QDir>
 #include <QFileInfo>
@@ -40,6 +39,3 @@ public:
     }
 
 };
-
-#endif //LASTUSEDSAVEDFILEDIRECTORY_H
-
diff --git a/Applications/DataExplorer/Base/OGSError.h b/Applications/DataExplorer/Base/OGSError.h
index 76749e0c438..da722616c5d 100644
--- a/Applications/DataExplorer/Base/OGSError.h
+++ b/Applications/DataExplorer/Base/OGSError.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef OGSERROR_H
-#define OGSERROR_H
+#pragma once
 
 class QString;
 
@@ -53,5 +52,3 @@ protected:
     OGSError();
     ~OGSError();
 };
-
-#endif //OGSERROR_H
diff --git a/Applications/DataExplorer/Base/QNonScalableGraphicsTextItem.h b/Applications/DataExplorer/Base/QNonScalableGraphicsTextItem.h
index a84d1176cc1..ce9d3677f00 100644
--- a/Applications/DataExplorer/Base/QNonScalableGraphicsTextItem.h
+++ b/Applications/DataExplorer/Base/QNonScalableGraphicsTextItem.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef QNONSCALABLETEXTITEM_H
-#define QNONSCALABLETEXTITEM_H
+#pragma once
 
 #include <QGraphicsTextItem>
 
@@ -32,5 +31,3 @@ public:
     void paint(QPainter* painter, const QStyleOptionGraphicsItem* option, QWidget* widget);
     virtual QRectF boundingRect() const;
 };
-
-#endif //QNONSCALABLETEXTITEM_H
diff --git a/Applications/DataExplorer/Base/QValueTooltipSlider.h b/Applications/DataExplorer/Base/QValueTooltipSlider.h
index c8653786f27..bdd247503c4 100644
--- a/Applications/DataExplorer/Base/QValueTooltipSlider.h
+++ b/Applications/DataExplorer/Base/QValueTooltipSlider.h
@@ -11,8 +11,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef QVALUETOOLTIPSLIDER_H
-#define QVALUETOOLTIPSLIDER_H
+#pragma once
 
 #include <QSlider>
 
@@ -31,5 +30,3 @@ public slots:
 
 protected:
 };
-
-#endif // QVALUETOOLTIPSLIDER_H
diff --git a/Applications/DataExplorer/Base/RecentFiles.h b/Applications/DataExplorer/Base/RecentFiles.h
index f71cf8f52dc..ec8d6b5456f 100644
--- a/Applications/DataExplorer/Base/RecentFiles.h
+++ b/Applications/DataExplorer/Base/RecentFiles.h
@@ -11,8 +11,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef RECENTFILES_H
-#define RECENTFILES_H
+#pragma once
 
 // ** INCLUDES **
 #include <QAction>
@@ -72,5 +71,3 @@ private:
     enum { _maxFiles = 5 };
     QAction* _fileActions[_maxFiles];
 };
-
-#endif // RECENTFILES_H
diff --git a/Applications/DataExplorer/Base/StrictDoubleValidator.h b/Applications/DataExplorer/Base/StrictDoubleValidator.h
index 38e72c7b46b..bb3cd3b1050 100644
--- a/Applications/DataExplorer/Base/StrictDoubleValidator.h
+++ b/Applications/DataExplorer/Base/StrictDoubleValidator.h
@@ -11,8 +11,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef STRICTDOUBLEVALIDATOR_H_
-#define STRICTDOUBLEVALIDATOR_H_
+#pragma once
 
 #include <QDoubleValidator>
 
@@ -40,5 +39,3 @@ public:
         return Acceptable;
     }
 };
-
-#endif /* STRICTDOUBLEVALIDATOR_H_ */
diff --git a/Applications/DataExplorer/Base/StrictIntValidator.h b/Applications/DataExplorer/Base/StrictIntValidator.h
index 43388762773..bb1ba32ab52 100644
--- a/Applications/DataExplorer/Base/StrictIntValidator.h
+++ b/Applications/DataExplorer/Base/StrictIntValidator.h
@@ -12,8 +12,7 @@
 
  */
 
-#ifndef STRICTINTVALIDATOR_H_
-#define STRICTINTVALIDATOR_H_
+#pragma once
 
 #include <QIntValidator>
 
@@ -37,5 +36,3 @@ public:
         return Acceptable;
     }
 };
-
-#endif /* STRICTINTVALIDATOR_H_ */
diff --git a/Applications/DataExplorer/Base/TreeItem.h b/Applications/DataExplorer/Base/TreeItem.h
index dcc2b7378a6..362c1789e19 100644
--- a/Applications/DataExplorer/Base/TreeItem.h
+++ b/Applications/DataExplorer/Base/TreeItem.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef QTREEITEM_H
-#define QTREEITEM_H
+#pragma once
 
 #include <QList>
 #include <QVariant>
@@ -46,5 +45,3 @@ private:
     QList<QVariant> _itemData;
     TreeItem* _parentItem;
 };
-
-#endif //QTREEITEM_H
diff --git a/Applications/DataExplorer/Base/TreeModel.h b/Applications/DataExplorer/Base/TreeModel.h
index 4a8e4744266..1323babbc78 100644
--- a/Applications/DataExplorer/Base/TreeModel.h
+++ b/Applications/DataExplorer/Base/TreeModel.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef QTREEMODEL_H
-#define QTREEMODEL_H
+#pragma once
 
 #include <QAbstractItemModel>
 
@@ -58,5 +57,3 @@ protected:
 private:
     void setupModelData(const QStringList &lines, TreeItem* parent);
 };
-
-#endif //QTREEMODEL_H
diff --git a/Applications/DataExplorer/Base/TreeModelIterator.h b/Applications/DataExplorer/Base/TreeModelIterator.h
index 0940dc6184f..7ed76018637 100644
--- a/Applications/DataExplorer/Base/TreeModelIterator.h
+++ b/Applications/DataExplorer/Base/TreeModelIterator.h
@@ -12,8 +12,7 @@
 
  */
 
-#ifndef TREEMODELITERATOR_H
-#define TREEMODELITERATOR_H
+#pragma once
 
 // ** INCLUDES **
 #include <QStack>
@@ -61,5 +60,3 @@ private:
     /// \brief The traversal implementation.
     TreeItem* next(const TreeItem* current);
 };
-
-#endif // TREEMODELITERATOR_H
diff --git a/Applications/DataExplorer/Base/modeltest.h b/Applications/DataExplorer/Base/modeltest.h
index c6f090e60e1..d2954429c0c 100644
--- a/Applications/DataExplorer/Base/modeltest.h
+++ b/Applications/DataExplorer/Base/modeltest.h
@@ -21,8 +21,7 @@
 **
 ****************************************************************************/
 
-#ifndef MODELTEST_H
-#define MODELTEST_H
+#pragma once
 
 #include <QtCore/QAbstractItemModel>
 #include <QtCore/QObject>
@@ -72,5 +71,3 @@ private:
 
     QList<QPersistentModelIndex> changing;
 };
-
-#endif
diff --git a/Applications/DataExplorer/DataView/AddLayerToMeshDialog.h b/Applications/DataExplorer/DataView/AddLayerToMeshDialog.h
index af9f4dfdfbc..1563895a211 100644
--- a/Applications/DataExplorer/DataView/AddLayerToMeshDialog.h
+++ b/Applications/DataExplorer/DataView/AddLayerToMeshDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef ADDLAYERTOMESHDIALOG_H
-#define ADDLAYERTOMESHDIALOG_H
+#pragma once
 
 #include "ui_AddLayerToMesh.h"
 
@@ -46,5 +45,3 @@ private slots:
     /// Instructions if the Cancel-Button has been pressed.
     void reject();
 };
-
-#endif //ADDLAYERTOMESHDIALOG_H
diff --git a/Applications/DataExplorer/DataView/BaseItem.h b/Applications/DataExplorer/DataView/BaseItem.h
index 444f5c24511..b5f897282b8 100644
--- a/Applications/DataExplorer/DataView/BaseItem.h
+++ b/Applications/DataExplorer/DataView/BaseItem.h
@@ -11,8 +11,7 @@
  *              http://www.opengeosys.org/project/license
  *
  */
-#ifndef BASEITEM_H
-#define BASEITEM_H
+#pragma once
 
 #include "Point.h"
 
@@ -61,5 +60,3 @@ private:
     /// visualization pipeline.
     vtkPolyDataAlgorithm* _vtkSource;
 };
-
-#endif //BASEITEM_H
diff --git a/Applications/DataExplorer/DataView/ColorTableModel.h b/Applications/DataExplorer/DataView/ColorTableModel.h
index 1b6da36ece1..97a94ac11d0 100644
--- a/Applications/DataExplorer/DataView/ColorTableModel.h
+++ b/Applications/DataExplorer/DataView/ColorTableModel.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef COLORTABLEMODEL_H
-#define COLORTABLEMODEL_H
+#pragma once
 
 #include <QAbstractTableModel>
 #include <QColor>
@@ -50,4 +49,3 @@ private:
 
     QList< QPair<QString, QColor> > _listOfPairs;
 };
-#endif // COLORTABLEMODEL_H
diff --git a/Applications/DataExplorer/DataView/ColorTableView.h b/Applications/DataExplorer/DataView/ColorTableView.h
index 80aa1629f4c..3892db6945c 100644
--- a/Applications/DataExplorer/DataView/ColorTableView.h
+++ b/Applications/DataExplorer/DataView/ColorTableView.h
@@ -11,8 +11,7 @@
  *              http://www.opengeosys.org/project/license
  *
  */
-#ifndef COLORTABLEVIEW_H
-#define COLORTABLEVIEW_H
+#pragma once
 
 #include <QItemDelegate>
 #include <QTableView>
@@ -46,6 +45,3 @@ public:
 
     QSize sizeHint( const QStyleOptionViewItem &option, const QModelIndex &index ) const;
 };
-
-#endif // COLORTABLEVIEW_H
-
diff --git a/Applications/DataExplorer/DataView/CondFromRasterDialog.h b/Applications/DataExplorer/DataView/CondFromRasterDialog.h
index d843785c81d..4be6b081793 100644
--- a/Applications/DataExplorer/DataView/CondFromRasterDialog.h
+++ b/Applications/DataExplorer/DataView/CondFromRasterDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef CONDFROMRASTERDIALOG_H
-#define CONDFROMRASTERDIALOG_H
+#pragma once
 
 #include "ui_CondFromRaster.h"
 #include <QDialog>
@@ -53,5 +52,3 @@ signals:
     void directNodesWritten(std::string);
     void transmitDisValues(std::vector< std::pair<std::size_t,double> >);
 };
-
-#endif //CONDFROMRASTERDIALOG_H
diff --git a/Applications/DataExplorer/DataView/CondItem.h b/Applications/DataExplorer/DataView/CondItem.h
index 931b4c68797..b4ac423753b 100644
--- a/Applications/DataExplorer/DataView/CondItem.h
+++ b/Applications/DataExplorer/DataView/CondItem.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef CONDITEM_H
-#define CONDITEM_H
+#pragma once
 
 #include "FEMCondition.h"
 #include "TreeItem.h"
@@ -43,5 +42,3 @@ public:
 private:
     const FEMCondition* _item;
 };
-
-#endif //CONDITEM_H
diff --git a/Applications/DataExplorer/DataView/CondObjectListItem.h b/Applications/DataExplorer/DataView/CondObjectListItem.h
index 420d166c620..272a7ee9d8a 100644
--- a/Applications/DataExplorer/DataView/CondObjectListItem.h
+++ b/Applications/DataExplorer/DataView/CondObjectListItem.h
@@ -12,8 +12,7 @@
  *
  *
  */
-#ifndef CONDOBJECTLISTITEM_H
-#define CONDOBJECTLISTITEM_H
+#pragma once
 
 #include "FEMCondition.h"
 #include "TreeItem.h"
@@ -74,5 +73,3 @@ private:
     FEMCondition::CondType _type;
     std::vector<FEMCondition*>* _cond_vec;
 };
-
-#endif //CONDOBJECTLISTITEM_H
diff --git a/Applications/DataExplorer/DataView/CreateStructuredGridDialog.h b/Applications/DataExplorer/DataView/CreateStructuredGridDialog.h
index a49ea00d892..29b9ae6cfd8 100644
--- a/Applications/DataExplorer/DataView/CreateStructuredGridDialog.h
+++ b/Applications/DataExplorer/DataView/CreateStructuredGridDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef CREATESTRUCTUREDGRIDDIALOG_H
-#define CREATESTRUCTUREDGRIDDIALOG_H
+#pragma once
 
 #include "ui_CreateStructuredGrid.h"
 #include <QDialog>
@@ -56,5 +55,3 @@ private:
 signals:
     void meshAdded(MeshLib::Mesh* mesh);
 };
-
-#endif // CREATESTRUCTUREDGRIDDIALOG_H
diff --git a/Applications/DataExplorer/DataView/DataExplorerSettingsDialog.h b/Applications/DataExplorer/DataView/DataExplorerSettingsDialog.h
index a9ba1e170b8..ed40b7a5dc9 100644
--- a/Applications/DataExplorer/DataView/DataExplorerSettingsDialog.h
+++ b/Applications/DataExplorer/DataView/DataExplorerSettingsDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef DATAEXPLORERSETTINGSDIALOG_H
-#define DATAEXPLORERSETTINGSDIALOG_H
+#pragma once
 
 #include "ui_DataExplorerSettings.h"
 #include <QDialog>
@@ -40,5 +39,3 @@ private slots:
     void reject() { this->done(QDialog::Rejected); };
 
 };
-
-#endif //DATAEXPLORERSETTINGSDIALOG_H
diff --git a/Applications/DataExplorer/DataView/DiagramView/DetailWindow.h b/Applications/DataExplorer/DataView/DiagramView/DetailWindow.h
index 82d8e7957f8..48f1c55414b 100644
--- a/Applications/DataExplorer/DataView/DiagramView/DetailWindow.h
+++ b/Applications/DataExplorer/DataView/DiagramView/DetailWindow.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef DETAILWINDOW_H
-#define DETAILWINDOW_H
+#pragma once
 
 #include "ui_DetailWindow.h"
 #include <QWidget>
@@ -65,5 +64,3 @@ private slots:
     void on_addDataButton_clicked();
     void on_closeButton_clicked();
 };
-
-#endif //DETAILWINDOW_H
diff --git a/Applications/DataExplorer/DataView/DiagramView/DiagramList.h b/Applications/DataExplorer/DataView/DiagramView/DiagramList.h
index f5d836502fe..1471bb6e66e 100644
--- a/Applications/DataExplorer/DataView/DiagramView/DiagramList.h
+++ b/Applications/DataExplorer/DataView/DiagramView/DiagramList.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef DIAGRAMLIST_H
-#define DIAGRAMLIST_H
+#pragma once
 
 #include <QColor>
 #include <QDateTime>
@@ -184,5 +183,3 @@ private:
     QColor _colour;
     QDateTime _startDate;
 };
-
-#endif //DIAGRAMLIST_H
diff --git a/Applications/DataExplorer/DataView/DiagramView/DiagramPrefsDialog.h b/Applications/DataExplorer/DataView/DiagramView/DiagramPrefsDialog.h
index 2e10920bfe9..696e81b577c 100644
--- a/Applications/DataExplorer/DataView/DiagramView/DiagramPrefsDialog.h
+++ b/Applications/DataExplorer/DataView/DiagramView/DiagramPrefsDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef DIAGRAMPREFSDIALOG_H
-#define DIAGRAMPREFSDIALOG_H
+#pragma once
 
 #include "ui_DiagramPrefs.h"
 #include <QMainWindow>
@@ -115,5 +114,3 @@ private slots:
 
 signals:
 };
-
-#endif //DIAGRAMPREFSDIALOG_H
diff --git a/Applications/DataExplorer/DataView/DiagramView/DiagramScene.h b/Applications/DataExplorer/DataView/DiagramView/DiagramScene.h
index 7c7e8b3f6e7..511ed66e63f 100644
--- a/Applications/DataExplorer/DataView/DiagramView/DiagramScene.h
+++ b/Applications/DataExplorer/DataView/DiagramView/DiagramScene.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef DIAGRAMSCENE_H
-#define DIAGRAMSCENE_H
+#pragma once
 
 #include "DiagramList.h"
 #include "QArrow.h"
@@ -79,5 +78,3 @@ private:
     QVector<QNonScalableGraphicsTextItem*> _xTicksText;
     QVector<QNonScalableGraphicsTextItem*> _yTicksText;
 };
-
-#endif //DIAGRAMSCENE_H
diff --git a/Applications/DataExplorer/DataView/DiagramView/DiagramView.h b/Applications/DataExplorer/DataView/DiagramView/DiagramView.h
index a9730818304..927eaa98daa 100644
--- a/Applications/DataExplorer/DataView/DiagramView/DiagramView.h
+++ b/Applications/DataExplorer/DataView/DiagramView/DiagramView.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef DIAGRAMVIEW_H
-#define DIAGRAMVIEW_H
+#pragma once
 
 #include "DiagramScene.h"
 #include <QGraphicsView>
@@ -61,5 +60,3 @@ private:
 
     DiagramScene* _scene;
 };
-
-#endif //DIAGRAMVIEW_H
diff --git a/Applications/DataExplorer/DataView/DiagramView/QArrow.h b/Applications/DataExplorer/DataView/DiagramView/QArrow.h
index 433cf351eb6..8df5ac7f365 100644
--- a/Applications/DataExplorer/DataView/DiagramView/QArrow.h
+++ b/Applications/DataExplorer/DataView/DiagramView/QArrow.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef QARROW_H
-#define QARROW_H
+#pragma once
 
 #include <QGraphicsItem>
 #include <QPen>
@@ -47,5 +46,3 @@ private:
     float _headWidth;
     QPen _arrowPen;
 };
-
-#endif //QARROW_H
diff --git a/Applications/DataExplorer/DataView/DiagramView/QGraphicsGrid.h b/Applications/DataExplorer/DataView/DiagramView/QGraphicsGrid.h
index 80c814686db..ba529f9c648 100644
--- a/Applications/DataExplorer/DataView/DiagramView/QGraphicsGrid.h
+++ b/Applications/DataExplorer/DataView/DiagramView/QGraphicsGrid.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef QGRAPHICSGRID_H
-#define QGRAPHICSGRID_H
+#pragma once
 
 #include <QGraphicsItem>
 #include <QPen>
@@ -68,5 +67,3 @@ private:
     int _numberOfYCells;
     bool _showTicks;
 };
-
-#endif //QGRAPHICSGRID_H
diff --git a/Applications/DataExplorer/DataView/DirectConditionGenerator.h b/Applications/DataExplorer/DataView/DirectConditionGenerator.h
index c4680257eaf..0985f0875a1 100644
--- a/Applications/DataExplorer/DataView/DirectConditionGenerator.h
+++ b/Applications/DataExplorer/DataView/DirectConditionGenerator.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef DIRECTCONDITIONGENERATOR_H
-#define DIRECTCONDITIONGENERATOR_H
+#pragma once
 
 #include <vector>
 #include <string>
@@ -38,6 +37,3 @@ private:
     std::vector< std::pair<std::size_t,double> > _direct_values;
 
 };
-
-#endif // DIRECTCONDITIONGENERATOR_H
-
diff --git a/Applications/DataExplorer/DataView/ElementTreeModel.h b/Applications/DataExplorer/DataView/ElementTreeModel.h
index 054ea455f56..eb860ac9573 100644
--- a/Applications/DataExplorer/DataView/ElementTreeModel.h
+++ b/Applications/DataExplorer/DataView/ElementTreeModel.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef ELEMENTTREEMODEL_H
-#define ELEMENTTREEMODEL_H
+#pragma once
 
 #include <array>
 #include "TreeModel.h"
@@ -52,5 +51,3 @@ private:
     vtkUnstructuredGridAlgorithm const* _mesh_source;
 
 };
-
-#endif //ELEMENTTREEMODEL_H
diff --git a/Applications/DataExplorer/DataView/ElementTreeView.h b/Applications/DataExplorer/DataView/ElementTreeView.h
index c093eed267e..a3531ba226d 100644
--- a/Applications/DataExplorer/DataView/ElementTreeView.h
+++ b/Applications/DataExplorer/DataView/ElementTreeView.h
@@ -11,8 +11,7 @@
  *              http://www.opengeosys.org/project/license
  *
  */
-#ifndef ELEMENTTREEVIEW_H
-#define ELEMENTTREEVIEW_H
+#pragma once
 
 #include <QTreeView>
 
@@ -40,7 +39,3 @@ signals:
     void nodeSelected(vtkUnstructuredGridAlgorithm const*const, unsigned, bool);
     void removeSelectedMeshComponent();
 };
-
-
-#endif // ELEMENTTREEVIEW_H
-
diff --git a/Applications/DataExplorer/DataView/GEOModels.h b/Applications/DataExplorer/DataView/GEOModels.h
index 4e33203348c..eebcf35cba6 100644
--- a/Applications/DataExplorer/DataView/GEOModels.h
+++ b/Applications/DataExplorer/DataView/GEOModels.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef GEOMODELS_H
-#define GEOMODELS_H
+#pragma once
 
 #include <QObject>
 
@@ -170,6 +169,3 @@ public:
 private:
     GEOModels& _geo_models;
 };
-
-
-#endif // GEOMODELS_H
diff --git a/Applications/DataExplorer/DataView/GMSHPrefsDialog.h b/Applications/DataExplorer/DataView/GMSHPrefsDialog.h
index c1b80d1717c..768b7d68862 100644
--- a/Applications/DataExplorer/DataView/GMSHPrefsDialog.h
+++ b/Applications/DataExplorer/DataView/GMSHPrefsDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef GMSHPREFSDIALOG_H
-#define GMSHPREFSDIALOG_H
+#pragma once
 
 #include "ui_GMSHPrefs.h"
 #include <QDialog>
@@ -56,5 +55,3 @@ private slots:
 signals:
     void requestMeshing(std::vector<std::string> &, unsigned, double, double, double, bool);
 };
-
-#endif //GMSHPREFSDIALOG_H
diff --git a/Applications/DataExplorer/DataView/GeoObjectListItem.h b/Applications/DataExplorer/DataView/GeoObjectListItem.h
index 5bf78816912..a85c9b86b89 100644
--- a/Applications/DataExplorer/DataView/GeoObjectListItem.h
+++ b/Applications/DataExplorer/DataView/GeoObjectListItem.h
@@ -12,8 +12,7 @@
  *
  *
  */
-#ifndef GEOOBJECTLISTITEM_H
-#define GEOOBJECTLISTITEM_H
+#pragma once
 
 #include "TreeItem.h"
 
@@ -88,5 +87,3 @@ private:
 
     GeoLib::GEOTYPE _type;
 };
-
-#endif //GEOOBJECTLISTITEM_H
diff --git a/Applications/DataExplorer/DataView/GeoOnMeshMappingDialog.h b/Applications/DataExplorer/DataView/GeoOnMeshMappingDialog.h
index aab8ff19236..985c6cde388 100644
--- a/Applications/DataExplorer/DataView/GeoOnMeshMappingDialog.h
+++ b/Applications/DataExplorer/DataView/GeoOnMeshMappingDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef GEOTOMESHMAPPINGDIALOG_H
-#define GEOTOMESHMAPPINGDIALOG_H
+#pragma once
 
 #include "ui_GeoOnMeshMapping.h"
 #include <QDialog>
@@ -55,5 +54,3 @@ private slots:
     void reject() { this->done(QDialog::Rejected); };
 
 };
-
-#endif //GEOTOMESHMAPPINGDIALOG_H
diff --git a/Applications/DataExplorer/DataView/GeoTabWidget.h b/Applications/DataExplorer/DataView/GeoTabWidget.h
index aa6f5ebd65d..825a3916c68 100644
--- a/Applications/DataExplorer/DataView/GeoTabWidget.h
+++ b/Applications/DataExplorer/DataView/GeoTabWidget.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef GEOTABWIDGET_H
-#define GEOTABWIDGET_H
+#pragma once
 
 // ** INCLUDES **
 #include "ui_GeoTabWidgetBase.h"
@@ -35,5 +34,3 @@ private slots:
     void enableRemoveButton(bool enable) { this->removeGeoPushButton->setEnabled(enable); };
 
 };
-
-#endif // GEOTABWIDGET_H
diff --git a/Applications/DataExplorer/DataView/GeoTreeItem.h b/Applications/DataExplorer/DataView/GeoTreeItem.h
index b113288c4ea..45d3c41a2c9 100644
--- a/Applications/DataExplorer/DataView/GeoTreeItem.h
+++ b/Applications/DataExplorer/DataView/GeoTreeItem.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef GEOTREEITEM_H
-#define GEOTREEITEM_H
+#pragma once
 
 #include "TreeItem.h"
 
@@ -44,5 +43,3 @@ public:
 private:
     const GeoLib::GeoObject* _item;
 };
-
-#endif //GEOTREEITEM_H
diff --git a/Applications/DataExplorer/DataView/GeoTreeModel.h b/Applications/DataExplorer/DataView/GeoTreeModel.h
index 6d380a00674..543a77ef9cf 100644
--- a/Applications/DataExplorer/DataView/GeoTreeModel.h
+++ b/Applications/DataExplorer/DataView/GeoTreeModel.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef GEOTREEMODEL_H
-#define GEOTREEMODEL_H
+#pragma once
 
 #include <vector>
 
@@ -96,5 +95,3 @@ private:
 
     std::vector<GeoTreeItem*> _lists;
 };
-
-#endif //GEOTREEMODEL_H
diff --git a/Applications/DataExplorer/DataView/GeoTreeView.h b/Applications/DataExplorer/DataView/GeoTreeView.h
index 251fa34c840..dd4f27cb9df 100644
--- a/Applications/DataExplorer/DataView/GeoTreeView.h
+++ b/Applications/DataExplorer/DataView/GeoTreeView.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef GEOTREEVIEW_H
-#define GEOTREEVIEW_H
+#pragma once
 
 #include "GeoType.h"
 
@@ -86,5 +85,3 @@ signals:
     void requestNameChangeDialog(const std::string&, const GeoLib::GEOTYPE, const std::size_t);
     //void saveFEMConditionsRequested(QString, QString);
 };
-
-#endif //GEOTREEVIEW_H
diff --git a/Applications/DataExplorer/DataView/LicenseDialog.h b/Applications/DataExplorer/DataView/LicenseDialog.h
index db142c41a05..0e9b60923e7 100644
--- a/Applications/DataExplorer/DataView/LicenseDialog.h
+++ b/Applications/DataExplorer/DataView/LicenseDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef LICENSEDIALOG_H
-#define LICENSEDIALOG_H
+#pragma once
 
 #include "ui_License.h"
 #include <QDialog>
@@ -36,5 +35,3 @@ private slots:
     void on_okPushButton_pressed();
 
 };
-
-#endif //LICENSEDIALOG_H
diff --git a/Applications/DataExplorer/DataView/LineEditDialog.h b/Applications/DataExplorer/DataView/LineEditDialog.h
index 7cb34e28d63..8db79316cf0 100644
--- a/Applications/DataExplorer/DataView/LineEditDialog.h
+++ b/Applications/DataExplorer/DataView/LineEditDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef LINEEDITDIALOG_H
-#define LINEEDITDIALOG_H
+#pragma once
 
 #include "ui_LineEdit.h"
 #include <QDialog>
@@ -64,5 +63,3 @@ signals:
                           bool);
     void triangulateSurface(const GeoLib::Polyline);
 };
-
-#endif //LINEEDITDIALOG_H
diff --git a/Applications/DataExplorer/DataView/LinearEditDialog.h b/Applications/DataExplorer/DataView/LinearEditDialog.h
index fed2d7e71b7..d35d57bb0a1 100644
--- a/Applications/DataExplorer/DataView/LinearEditDialog.h
+++ b/Applications/DataExplorer/DataView/LinearEditDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef LINEAREDITDIALOG_H
-#define LINEAREDITDIALOG_H
+#pragma once
 
 #include "ui_LinearEdit.h"
 #include <QDialog>
@@ -48,5 +47,3 @@ private slots:
 signals:
     void transmitDisValues(std::vector< std::pair<std::size_t,double> >);
 };
-
-#endif //LINEAREDITDIALOG_H
diff --git a/Applications/DataExplorer/DataView/MergeGeometriesDialog.h b/Applications/DataExplorer/DataView/MergeGeometriesDialog.h
index d9d51feb356..ad9c1bac5f5 100644
--- a/Applications/DataExplorer/DataView/MergeGeometriesDialog.h
+++ b/Applications/DataExplorer/DataView/MergeGeometriesDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MERGEGEOMETRIESDIALOG_H
-#define MERGEGEOMETRIESDIALOG_H
+#pragma once
 
 #include "ui_MergeGeometries.h"
 #include <QDialog>
@@ -57,5 +56,3 @@ private slots:
     /// Instructions if the Cancel-Button has been pressed.
     void reject();
 };
-
-#endif //MERGEGEOMETRIESDIALOG_H
diff --git a/Applications/DataExplorer/DataView/MeshAnalysisDialog.h b/Applications/DataExplorer/DataView/MeshAnalysisDialog.h
index a53aa896e7a..7fde240dc43 100644
--- a/Applications/DataExplorer/DataView/MeshAnalysisDialog.h
+++ b/Applications/DataExplorer/DataView/MeshAnalysisDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MESHANALYSISDIALOG_H
-#define MESHANALYSISDIALOG_H
+#pragma once
 
 #include <memory>
 
@@ -55,5 +54,3 @@ private slots:
     /// Closes the dialog
     void on_closeButton_pressed() { this->close(); }
 };
-
-#endif //MESHANALYSISDIALOG_H
diff --git a/Applications/DataExplorer/DataView/MeshElementRemovalDialog.h b/Applications/DataExplorer/DataView/MeshElementRemovalDialog.h
index 3a1078f2d2a..1c0778f3a04 100644
--- a/Applications/DataExplorer/DataView/MeshElementRemovalDialog.h
+++ b/Applications/DataExplorer/DataView/MeshElementRemovalDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MESHELEMENTREMOVALDIALOG_H
-#define MESHELEMENTREMOVALDIALOG_H
+#pragma once
 
 #include "ui_MeshElementRemoval.h"
 #include <QDialog>
@@ -57,5 +56,3 @@ private:
 signals:
     void meshAdded(MeshLib::Mesh* mesh);
 };
-
-#endif //MESHELEMENTREMOVALDIALOG_H
diff --git a/Applications/DataExplorer/DataView/MeshLayerEditDialog.h b/Applications/DataExplorer/DataView/MeshLayerEditDialog.h
index ff07914c41d..bca05f792bf 100644
--- a/Applications/DataExplorer/DataView/MeshLayerEditDialog.h
+++ b/Applications/DataExplorer/DataView/MeshLayerEditDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MESHLAYEREDITDIALOG_H
-#define MESHLAYEREDITDIALOG_H
+#pragma once
 
 #include "ui_MeshLayerEdit.h"
 #include <QDialog>
@@ -81,5 +80,3 @@ private slots:
 signals:
     void mshEditFinished(MeshLib::Mesh*);
 };
-
-#endif //MESHLAYEREDITDIALOG_H
diff --git a/Applications/DataExplorer/DataView/MeshMapping2DDialog.h b/Applications/DataExplorer/DataView/MeshMapping2DDialog.h
index f563c2d8e13..7702cd357b4 100644
--- a/Applications/DataExplorer/DataView/MeshMapping2DDialog.h
+++ b/Applications/DataExplorer/DataView/MeshMapping2DDialog.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MESHMAPPING2DDIALOG_H
-#define MESHMAPPING2DDIALOG_H
+#pragma once
 
 #include "ui_MeshMapping2D.h"
 
@@ -43,5 +42,3 @@ private slots:
     /// Instructions if the Cancel-Button has been pressed.
     void reject() { this->done(QDialog::Rejected); }
 };
-
-#endif //MESHMAPPING2DDIALOG_H
diff --git a/Applications/DataExplorer/DataView/MeshQualitySelectionDialog.h b/Applications/DataExplorer/DataView/MeshQualitySelectionDialog.h
index d92eadb00cb..72502837624 100644
--- a/Applications/DataExplorer/DataView/MeshQualitySelectionDialog.h
+++ b/Applications/DataExplorer/DataView/MeshQualitySelectionDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MESHQUALITYSELECTIONDIALOG_H
-#define MESHQUALITYSELECTIONDIALOG_H
+#pragma once
 
 #include "MeshEnums.h"
 #include "ui_MeshQualitySelection.h"
@@ -52,5 +51,3 @@ private slots:
     void accept();
     void reject();
 };
-
-#endif //MESHQUALITYSELECTIONDIALOG_H
diff --git a/Applications/DataExplorer/DataView/MeshValueEditDialog.h b/Applications/DataExplorer/DataView/MeshValueEditDialog.h
index 75bf93f52bb..df4de5b0a15 100644
--- a/Applications/DataExplorer/DataView/MeshValueEditDialog.h
+++ b/Applications/DataExplorer/DataView/MeshValueEditDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MESHVALUEEDITDIALOG_H
-#define MESHVALUEEDITDIALOG_H
+#pragma once
 
 #include "ui_MeshValueEdit.h"
 
@@ -51,5 +50,3 @@ private slots:
 signals:
     void valueEditFinished(MeshLib::Mesh*);
 };
-
-#endif //MESHVALUEEDITDIALOG_H
diff --git a/Applications/DataExplorer/DataView/ModelTreeItem.h b/Applications/DataExplorer/DataView/ModelTreeItem.h
index 0df9866a298..58a86176b42 100644
--- a/Applications/DataExplorer/DataView/ModelTreeItem.h
+++ b/Applications/DataExplorer/DataView/ModelTreeItem.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef QMODELTREEITEM_H
-#define QMODELTREEITEM_H
+#pragma once
 
 #include "BaseItem.h"
 #include "Station.h"
@@ -52,5 +51,3 @@ private:
     BaseItem* _item;
     GeoLib::Station* _stn;
 };
-
-#endif //QMODELTREEITEM_H
diff --git a/Applications/DataExplorer/DataView/ModellingTabWidget.h b/Applications/DataExplorer/DataView/ModellingTabWidget.h
index 7001914e4b7..87bcb53b388 100644
--- a/Applications/DataExplorer/DataView/ModellingTabWidget.h
+++ b/Applications/DataExplorer/DataView/ModellingTabWidget.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MODELLINGTABWIDGET_H
-#define MODELLINGTABWIDGET_H
+#pragma once
 
 // ** INCLUDES **
 #include "ui_ModellingTabWidgetBase.h"
@@ -32,5 +31,3 @@ private slots:
 
 signals:
 };
-
-#endif // MODELLINGTABWIDGET_H
diff --git a/Applications/DataExplorer/DataView/MshEditDialog.h b/Applications/DataExplorer/DataView/MshEditDialog.h
index 4c8a476d538..48144a717eb 100644
--- a/Applications/DataExplorer/DataView/MshEditDialog.h
+++ b/Applications/DataExplorer/DataView/MshEditDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MSHEDITDIALOG_H
-#define MSHEDITDIALOG_H
+#pragma once
 
 #include "ui_MshEdit.h"
 #include <QDialog>
@@ -82,5 +81,3 @@ private slots:
 signals:
     void mshEditFinished(MeshLib::Mesh*);
 };
-
-#endif //MSHEDITDIALOG_H
diff --git a/Applications/DataExplorer/DataView/MshItem.h b/Applications/DataExplorer/DataView/MshItem.h
index 71a11dc676e..be5eb456eca 100644
--- a/Applications/DataExplorer/DataView/MshItem.h
+++ b/Applications/DataExplorer/DataView/MshItem.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MSHITEM_H
-#define MSHITEM_H
+#pragma once
 
 #include "TreeItem.h"
 
@@ -47,5 +46,3 @@ public:
 private:
     MeshLib::VtkMappedMeshSource * _mesh_source;
 };
-
-#endif //MSHITEM_H
diff --git a/Applications/DataExplorer/DataView/MshModel.h b/Applications/DataExplorer/DataView/MshModel.h
index adcde8ff6cf..a0f4d9bef34 100644
--- a/Applications/DataExplorer/DataView/MshModel.h
+++ b/Applications/DataExplorer/DataView/MshModel.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MSHMODEL_H
-#define MSHMODEL_H
+#pragma once
 
 // ** INCLUDES **
 #ifndef Q_MOC_RUN  // See: https://bugreports.qt-project.org/browse/QTBUG-22829
@@ -84,5 +83,3 @@ signals:
     void meshAdded(MshModel*, const QModelIndex&);
     void meshRemoved(MshModel*, const QModelIndex&);
 };
-
-#endif // MSHMODEL_H
diff --git a/Applications/DataExplorer/DataView/MshTabWidget.h b/Applications/DataExplorer/DataView/MshTabWidget.h
index 69a8c263218..ec7b8196214 100644
--- a/Applications/DataExplorer/DataView/MshTabWidget.h
+++ b/Applications/DataExplorer/DataView/MshTabWidget.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MSHTABWIDGET_H
-#define MSHTABWIDGET_H
+#pragma once
 
 // ** INCLUDES **
 #include "ui_MshTabWidgetBase.h"
@@ -32,5 +31,3 @@ private slots:
     void enableSaveButton(bool enable) { this->saveMeshPushButton->setEnabled(enable); };
     void enableRemoveButton(bool enable) { this->removeMeshPushButton->setEnabled(enable); };
 };
-
-#endif // MSHTABWIDGET_H
diff --git a/Applications/DataExplorer/DataView/MshView.h b/Applications/DataExplorer/DataView/MshView.h
index a187a6c6a87..4eb055ebcd1 100644
--- a/Applications/DataExplorer/DataView/MshView.h
+++ b/Applications/DataExplorer/DataView/MshView.h
@@ -11,8 +11,7 @@
  *              http://www.opengeosys.org/project/license
  *
  */
-#ifndef MSHVIEW_H
-#define MSHVIEW_H
+#pragma once
 
 #include "Point.h"
 #include "GeoType.h"
@@ -110,4 +109,3 @@ signals:
     void saveMeshAction();
 
 };
-#endif // MSHVIEW_H
diff --git a/Applications/DataExplorer/DataView/NetCdfConfigureDialog.h b/Applications/DataExplorer/DataView/NetCdfConfigureDialog.h
index 7e4d500abd0..6371f44127d 100644
--- a/Applications/DataExplorer/DataView/NetCdfConfigureDialog.h
+++ b/Applications/DataExplorer/DataView/NetCdfConfigureDialog.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NETCDFCONFIGUREDIALOG_H
-#define NETCDFCONFIGUREDIALOG_H
+#pragma once
 
 #include <netcdfcpp.h>
 
@@ -73,6 +72,3 @@ private:
     std::string _currentPath;
     std::vector<int> _id_map;
 };
-
-#endif //NETCDFCONFIGUREDIALOG_H
-
diff --git a/Applications/DataExplorer/DataView/SHPImportDialog.h b/Applications/DataExplorer/DataView/SHPImportDialog.h
index 204a86d238c..2b67a363c5d 100644
--- a/Applications/DataExplorer/DataView/SHPImportDialog.h
+++ b/Applications/DataExplorer/DataView/SHPImportDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef SHPIMPORTDIALOG_H
-#define SHPIMPORTDIALOG_H
+#pragma once
 
 #include <QDialog>
 
@@ -71,5 +70,3 @@ private slots:
 signals:
     void shpLoaded(QString);
 };
-
-#endif //SHPIMPORTDIALOG_H
diff --git a/Applications/DataExplorer/DataView/SaveMeshDialog.h b/Applications/DataExplorer/DataView/SaveMeshDialog.h
index 2e0dcd5982c..0e371636be7 100644
--- a/Applications/DataExplorer/DataView/SaveMeshDialog.h
+++ b/Applications/DataExplorer/DataView/SaveMeshDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef SAVEMESHDIALOG_H
-#define SAVEMESHDIALOG_H
+#pragma once
 
 #include "ui_SaveMesh.h"
 #include <QDialog>
@@ -49,5 +48,3 @@ private:
     MeshLib::Mesh const& _mesh;
 
 };
-
-#endif //SAVEMESHDIALOG_H
diff --git a/Applications/DataExplorer/DataView/SelectMeshDialog.h b/Applications/DataExplorer/DataView/SelectMeshDialog.h
index 72d037a2b2c..dcc1c4e1f94 100644
--- a/Applications/DataExplorer/DataView/SelectMeshDialog.h
+++ b/Applications/DataExplorer/DataView/SelectMeshDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef SELECTMESHDIALOG_H
-#define SELECTMESHDIALOG_H
+#pragma once
 
 #include <QDialog>
 
@@ -62,5 +61,3 @@ private slots:
 signals:
     //void requestNameChange(const std::string&, const GeoLib::GEOTYPE, std::size_t, std::string);
 };
-
-#endif //SELECTMESHDIALOG_H
diff --git a/Applications/DataExplorer/DataView/SetNameDialog.h b/Applications/DataExplorer/DataView/SetNameDialog.h
index 3c71dd25041..5afe0ea52d4 100644
--- a/Applications/DataExplorer/DataView/SetNameDialog.h
+++ b/Applications/DataExplorer/DataView/SetNameDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef SETNAMEDIALOG_H
-#define SETNAMEDIALOG_H
+#pragma once
 
 #include "GeoType.h"
 
@@ -54,5 +53,3 @@ private slots:
     /// Instructions if the Cancel-Button has been pressed.
     void reject();
 };
-
-#endif //SETNAMEDIALOG_H
diff --git a/Applications/DataExplorer/DataView/StationTabWidget.h b/Applications/DataExplorer/DataView/StationTabWidget.h
index 2c16648fced..2cfefb80502 100644
--- a/Applications/DataExplorer/DataView/StationTabWidget.h
+++ b/Applications/DataExplorer/DataView/StationTabWidget.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef STATIONTABWIDGET_H
-#define STATIONTABWIDGET_H
+#pragma once
 
 // ** INCLUDES **
 #include "ui_StationTabWidgetBase.h"
@@ -34,5 +33,3 @@ private slots:
     void enableSaveButton(bool enable) { this->saveStnPushButton->setEnabled(enable); };
     void enableRemoveButton(bool enable) { this->removeStnPushButton->setEnabled(enable); };
 };
-
-#endif // STATIONTABWIDGET_H
diff --git a/Applications/DataExplorer/DataView/StationTreeModel.h b/Applications/DataExplorer/DataView/StationTreeModel.h
index 3af6c01a3a3..a303250304a 100644
--- a/Applications/DataExplorer/DataView/StationTreeModel.h
+++ b/Applications/DataExplorer/DataView/StationTreeModel.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef QSTATIONTREEMODEL_H
-#define QSTATIONTREEMODEL_H
+#pragma once
 
 #include <vector>
 
@@ -61,5 +60,3 @@ public:
 private:
     std::vector<ModelTreeItem*> _lists;
 };
-
-#endif //QSTATIONTREEMODEL_H
diff --git a/Applications/DataExplorer/DataView/StationTreeView.h b/Applications/DataExplorer/DataView/StationTreeView.h
index 1ac4339e85e..3b5ed7c73e3 100644
--- a/Applications/DataExplorer/DataView/StationTreeView.h
+++ b/Applications/DataExplorer/DataView/StationTreeView.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef QSTATIONTREEVIEW_H
-#define QSTATIONTREEVIEW_H
+#pragma once
 
 #include "Station.h"
 
@@ -81,5 +80,3 @@ signals:
     void stationListSaved(QString listName, QString fileName);
     void diagramRequested(QModelIndex&);
 };
-
-#endif //QSTATIONTREEVIEW_H
diff --git a/Applications/DataExplorer/DataView/StratView/StratBar.h b/Applications/DataExplorer/DataView/StratView/StratBar.h
index fe118bb114f..66b39987ab2 100644
--- a/Applications/DataExplorer/DataView/StratView/StratBar.h
+++ b/Applications/DataExplorer/DataView/StratView/StratBar.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef STRATBAR_H
-#define STRATBAR_H
+#pragma once
 
 #include <cmath>
 
@@ -63,5 +62,3 @@ private:
     GeoLib::StationBorehole* _station;
     std::map<std::string, DataHolderLib::Color> _stratColors;
 };
-
-#endif //STRATBAR_H
diff --git a/Applications/DataExplorer/DataView/StratView/StratScene.h b/Applications/DataExplorer/DataView/StratView/StratScene.h
index 1bf01aa337f..03fb6688343 100644
--- a/Applications/DataExplorer/DataView/StratView/StratScene.h
+++ b/Applications/DataExplorer/DataView/StratView/StratScene.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef STRATSCENE_H
-#define STRATSCENE_H
+#pragma once
 
 #include <QGraphicsScene>
 
@@ -55,5 +54,3 @@ private:
     StratBar* addStratBar(GeoLib::StationBorehole* station,
                           std::map<std::string, DataHolderLib::Color>* stratColors = nullptr);
 };
-
-#endif //STRATSCENE_H
diff --git a/Applications/DataExplorer/DataView/StratView/StratView.h b/Applications/DataExplorer/DataView/StratView/StratView.h
index 87c61dd6602..b55b30db4eb 100644
--- a/Applications/DataExplorer/DataView/StratView/StratView.h
+++ b/Applications/DataExplorer/DataView/StratView/StratView.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef STRATVIEW_H
-#define STRATVIEW_H
+#pragma once
 
 #include "StratScene.h"
 #include <QGraphicsView>
@@ -69,5 +68,3 @@ private:
 
     StratScene* _scene;
 };
-
-#endif //STRATVIEW_H
diff --git a/Applications/DataExplorer/DataView/StratView/StratWindow.h b/Applications/DataExplorer/DataView/StratView/StratWindow.h
index d3f235ad38f..16da35d466f 100644
--- a/Applications/DataExplorer/DataView/StratView/StratWindow.h
+++ b/Applications/DataExplorer/DataView/StratView/StratWindow.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef STRATWINDOW_H
-#define STRATWINDOW_H
+#pragma once
 
 #include "ui_StratWindow.h"
 #include <QWidget>
@@ -49,5 +48,3 @@ private:
 private slots:
     void on_closeButton_clicked();
 };
-
-#endif //STRATWINDOW_H
diff --git a/Applications/DataExplorer/DataView/SurfaceExtractionDialog.h b/Applications/DataExplorer/DataView/SurfaceExtractionDialog.h
index af3fa26df1c..ad482c3b457 100644
--- a/Applications/DataExplorer/DataView/SurfaceExtractionDialog.h
+++ b/Applications/DataExplorer/DataView/SurfaceExtractionDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef SURFACEEXTRACTIONDIALOG_H
-#define SURFACEEXTRACTIONDIALOG_H
+#pragma once
 
 #include "ui_SurfaceExtraction.h"
 #include <QDialog>
@@ -49,5 +48,3 @@ private:
     int _tolerance;
     MathLib::Vector3 _dir;
 };
-
-#endif //SURFACEEXTRACTIONDIALOG_H
diff --git a/Applications/DataExplorer/VtkAct/VtkCustomInteractorStyle.h b/Applications/DataExplorer/VtkAct/VtkCustomInteractorStyle.h
index 23680e6b753..04b480b6515 100644
--- a/Applications/DataExplorer/VtkAct/VtkCustomInteractorStyle.h
+++ b/Applications/DataExplorer/VtkAct/VtkCustomInteractorStyle.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKCUSTOMINTERACTORSTYLE_H
-#define VTKCUSTOMINTERACTORSTYLE_H
+#pragma once
 
 // ** INCLUDES **
 #include <QObject>
@@ -99,6 +98,3 @@ signals:
     void clearElementView();
 
 };
-
-
-#endif // VTKINTERACTORSTYLE_H
diff --git a/Applications/DataExplorer/VtkAct/VtkPickCallback.h b/Applications/DataExplorer/VtkAct/VtkPickCallback.h
index 774e7f2d816..baaaf9e8b9c 100644
--- a/Applications/DataExplorer/VtkAct/VtkPickCallback.h
+++ b/Applications/DataExplorer/VtkAct/VtkPickCallback.h
@@ -13,8 +13,7 @@
  *
  */
 
-#ifndef VTKPICKCALLBACK_H
-#define VTKPICKCALLBACK_H
+#pragma once
 
 // ** INCLUDES **
 #include <QObject>
@@ -42,5 +41,3 @@ signals:
     /// Is emitted when an vtkActor was picked.
     void actorPicked (vtkProp3D* actor);
 };
-
-#endif // VTKPICKCALLBACK_H
diff --git a/Applications/DataExplorer/VtkVis/MeshFromRasterDialog.h b/Applications/DataExplorer/VtkVis/MeshFromRasterDialog.h
index 80d69a98892..e474792a216 100644
--- a/Applications/DataExplorer/VtkVis/MeshFromRasterDialog.h
+++ b/Applications/DataExplorer/VtkVis/MeshFromRasterDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MSHFROMRASTERDIALOG_H
-#define MSHFROMRASTERDIALOG_H
+#pragma once
 
 #include "ui_MeshFromRaster.h"
 
@@ -57,5 +56,3 @@ private:
     MeshLib::UseIntensityAs _intensity_selection;
 
 };
-
-#endif //MSHFROMRASTERDIALOG_H
diff --git a/Applications/DataExplorer/VtkVis/OGSFilterInfo.h b/Applications/DataExplorer/VtkVis/OGSFilterInfo.h
index f21c9bcff4f..ec99f44a0c0 100644
--- a/Applications/DataExplorer/VtkVis/OGSFilterInfo.h
+++ b/Applications/DataExplorer/VtkVis/OGSFilterInfo.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef OGSFILTERINFO_H
-#define OGSFILTERINFO_H
+#pragma once
 
 #include "VtkOGSFilter.h"
 #include <string>
@@ -41,5 +40,3 @@ private:
     VtkOGSFilter::OGSVisFilter _filter;
     VtkTargetObject _target;
 };
-
-#endif // OGSFILTERINFO_H
diff --git a/Applications/DataExplorer/VtkVis/QVtkDataSetMapper.h b/Applications/DataExplorer/VtkVis/QVtkDataSetMapper.h
index 30419cf90c7..596782ba698 100644
--- a/Applications/DataExplorer/VtkVis/QVtkDataSetMapper.h
+++ b/Applications/DataExplorer/VtkVis/QVtkDataSetMapper.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef QVTKDATASETMAPPER_H
-#define QVTKDATASETMAPPER_H
+#pragma once
 
 #include <QObject>
 #include <vtkDataSetMapper.h>
@@ -48,5 +47,3 @@ private:
     QVtkDataSetMapper(const QVtkDataSetMapper&); // Not implemented.
     void operator=(const QVtkDataSetMapper&); // Not implemented
 };
-
-#endif // QVTKDATASETMAPPER_H
diff --git a/Applications/DataExplorer/VtkVis/VisPrefsDialog.h b/Applications/DataExplorer/VtkVis/VisPrefsDialog.h
index 7bdcb96d538..ac76e0d708c 100644
--- a/Applications/DataExplorer/VtkVis/VisPrefsDialog.h
+++ b/Applications/DataExplorer/VtkVis/VisPrefsDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VISPREFSDIALOG_H
-#define VISPREFSDIALOG_H
+#pragma once
 
 #include "Point.h"
 #include "ui_VisPrefs.h"
@@ -59,5 +58,3 @@ private:
     GeoLib::Point _above;
     GeoLib::Point _below;
 };
-
-#endif //VISPREFSDIALOG_H
diff --git a/Applications/DataExplorer/VtkVis/VisualizationWidget.h b/Applications/DataExplorer/VtkVis/VisualizationWidget.h
index 21e57760d19..68aadb2abcf 100644
--- a/Applications/DataExplorer/VtkVis/VisualizationWidget.h
+++ b/Applications/DataExplorer/VtkVis/VisualizationWidget.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VISUALIZATIONWIDGET_H
-#define VISUALIZATIONWIDGET_H
+#pragma once
 
 // ** INCLUDES **
 #include "ui_VisualizationWidgetBase.h"
@@ -110,5 +109,3 @@ private:
     VtkPickCallback* _vtkPickCallback;
     bool _isShowAllOnLoad;
 };
-
-#endif // VISUALIZATIONWIDGET_H
diff --git a/Applications/DataExplorer/VtkVis/VtkAddFilterDialog.h b/Applications/DataExplorer/VtkVis/VtkAddFilterDialog.h
index 72e36ad60b6..2086a34ed61 100644
--- a/Applications/DataExplorer/VtkVis/VtkAddFilterDialog.h
+++ b/Applications/DataExplorer/VtkVis/VtkAddFilterDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKADDFILTERDIALOG_H
-#define VTKADDFILTERDIALOG_H
+#pragma once
 
 // ** INCLUDES **
 #include "ui_VtkAddFilterDialogBase.h"
@@ -45,5 +44,3 @@ private:
     VtkVisPipeline& _pipeline;
     QModelIndex _parentIndex;
 };
-
-#endif // VTKADDFILTERDIALOG_H
diff --git a/Applications/DataExplorer/VtkVis/VtkAlgorithmProperties.h b/Applications/DataExplorer/VtkVis/VtkAlgorithmProperties.h
index 487425c2455..10dbe7a6bd8 100644
--- a/Applications/DataExplorer/VtkVis/VtkAlgorithmProperties.h
+++ b/Applications/DataExplorer/VtkVis/VtkAlgorithmProperties.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKALGORITHMPROPERTIES_H
-#define VTKALGORITHMPROPERTIES_H
+#pragma once
 
 // ** INCLUDES **
 #include <QList>
@@ -235,5 +234,3 @@ protected:
 signals:
     void ScalarVisibilityChanged(bool on);
 };
-
-#endif // VTKALGORITHMPROPERTIES_H
diff --git a/Applications/DataExplorer/VtkVis/VtkAlgorithmPropertyCheckbox.h b/Applications/DataExplorer/VtkVis/VtkAlgorithmPropertyCheckbox.h
index 4db988b48b3..3ed35df96e3 100644
--- a/Applications/DataExplorer/VtkVis/VtkAlgorithmPropertyCheckbox.h
+++ b/Applications/DataExplorer/VtkVis/VtkAlgorithmPropertyCheckbox.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKALGORITHMPROPERTIESCHECKBOX_H
-#define VTKALGORITHMPROPERTIESCHECKBOX_H
+#pragma once
 
 #include <QCheckBox>
 
@@ -45,5 +44,3 @@ private slots:
     /// @brief This slots is automatically called when the checkbox state changed.
     void setNewValue(int state);
 };
-
-#endif // VTKALGORITHMPROPERTIESCHECKBOX_H
diff --git a/Applications/DataExplorer/VtkVis/VtkAlgorithmPropertyLineEdit.h b/Applications/DataExplorer/VtkVis/VtkAlgorithmPropertyLineEdit.h
index 56f3c340d62..6045b33e291 100644
--- a/Applications/DataExplorer/VtkVis/VtkAlgorithmPropertyLineEdit.h
+++ b/Applications/DataExplorer/VtkVis/VtkAlgorithmPropertyLineEdit.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKALGORITHMPROPERTYLINEEDIT_H
-#define VTKALGORITHMPROPERTYLINEEDIT_H
+#pragma once
 
 #include <QLineEdit>
 #include <QVariant>
@@ -50,5 +49,3 @@ private slots:
     /// @brief This slots is automatically called when the text changed.
     void setNewValue();
 };
-
-#endif // VTKALGORITHMPROPERTYLINEEDIT_H
diff --git a/Applications/DataExplorer/VtkVis/VtkAlgorithmPropertyVectorEdit.h b/Applications/DataExplorer/VtkVis/VtkAlgorithmPropertyVectorEdit.h
index cb78d0ff1cc..c697818960a 100644
--- a/Applications/DataExplorer/VtkVis/VtkAlgorithmPropertyVectorEdit.h
+++ b/Applications/DataExplorer/VtkVis/VtkAlgorithmPropertyVectorEdit.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKALGORITHMPROPERTYVECTOREDIT_H
-#define VTKALGORITHMPROPERTYVECTOREDIT_H
+#pragma once
 
 #include <QList>
 #include <QVariant>
@@ -54,5 +53,3 @@ signals:
     /// @brief Is emitted when text of one the line edits changed.
     void editingFinished();
 };
-
-#endif // VTKALGORITHMPROPERTYVECTOREDIT_H
diff --git a/Applications/DataExplorer/VtkVis/VtkAppendArrayFilter.h b/Applications/DataExplorer/VtkVis/VtkAppendArrayFilter.h
index 604a0430709..60ac3fb2410 100644
--- a/Applications/DataExplorer/VtkVis/VtkAppendArrayFilter.h
+++ b/Applications/DataExplorer/VtkVis/VtkAppendArrayFilter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKAPPENDARRAYFILTER_H
-#define VTKAPPENDARRAYFILTER_H
+#pragma once
 
 // ** INCLUDES **
 #include "VtkAlgorithmProperties.h"
@@ -58,5 +57,3 @@ private:
     std::vector<double> _array;
     std::string _array_name;
 };
-
-#endif // VTKAPPENDARRAYFILTER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkBGImageSource.h b/Applications/DataExplorer/VtkVis/VtkBGImageSource.h
index 509164d8c33..948aedc0889 100644
--- a/Applications/DataExplorer/VtkVis/VtkBGImageSource.h
+++ b/Applications/DataExplorer/VtkVis/VtkBGImageSource.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKBGIMAGESOURCE_H
-#define VTKBGIMAGESOURCE_H
+#pragma once
 
 // ** INCLUDES **
 #include <vtkTextureMapToPlane.h>
@@ -48,5 +47,3 @@ private:
     std::pair<double, double> _origin;
     double _cellsize;
 };
-
-#endif // VTKBGIMAGESOURCE_H
diff --git a/Applications/DataExplorer/VtkVis/VtkColorByHeightFilter.h b/Applications/DataExplorer/VtkVis/VtkColorByHeightFilter.h
index 02b83c2418b..6202918e8ce 100644
--- a/Applications/DataExplorer/VtkVis/VtkColorByHeightFilter.h
+++ b/Applications/DataExplorer/VtkVis/VtkColorByHeightFilter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKCOLORBYHEIGHTFILTER_H
-#define VTKCOLORBYHEIGHTFILTER_H
+#pragma once
 
 // ** INCLUDES **
 #include "VtkAlgorithmProperties.h"
@@ -81,5 +80,3 @@ protected:
     double _tableRange[2];
     double _tableRangeScaling;
 };
-
-#endif // VTKCOLORBYHEIGHTFILTER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkColorLookupTable.h b/Applications/DataExplorer/VtkVis/VtkColorLookupTable.h
index 88b5e028016..5b685fd1178 100644
--- a/Applications/DataExplorer/VtkVis/VtkColorLookupTable.h
+++ b/Applications/DataExplorer/VtkVis/VtkColorLookupTable.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKCOLORLOOKUPTABLE_H
-#define VTKCOLORLOOKUPTABLE_H
+#pragma once
 
 // ** INCLUDES **
 #include <cassert>
@@ -95,5 +94,3 @@ private:
     std::map<double, unsigned char*> _dict;
     DataHolderLib::LUTType _type;
 };
-
-#endif // VTKCOLORLOOKUPTABLE_H
diff --git a/Applications/DataExplorer/VtkVis/VtkCompositeColorByHeightFilter.h b/Applications/DataExplorer/VtkVis/VtkCompositeColorByHeightFilter.h
index 90db8eac7e9..220f31ac8e4 100644
--- a/Applications/DataExplorer/VtkVis/VtkCompositeColorByHeightFilter.h
+++ b/Applications/DataExplorer/VtkVis/VtkCompositeColorByHeightFilter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKCOMPOSITECOLORBYHEIGHTFILTER_H
-#define VTKCOMPOSITECOLORBYHEIGHTFILTER_H
+#pragma once
 
 #include "VtkCompositeFilter.h"
 
@@ -32,5 +31,3 @@ public:
 
 protected:
 };
-
-#endif // VTKCOMPOSITECOLORBYHEIGHTFILTER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkCompositeColormapToImageFilter.h b/Applications/DataExplorer/VtkVis/VtkCompositeColormapToImageFilter.h
index caed44fda1a..68c33443216 100644
--- a/Applications/DataExplorer/VtkVis/VtkCompositeColormapToImageFilter.h
+++ b/Applications/DataExplorer/VtkVis/VtkCompositeColormapToImageFilter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKCOMPOSITECOLORMAPTOIMAGEFILTER_H
-#define VTKCOMPOSITECOLORMAPTOIMAGEFILTER_H
+#pragma once
 
 #include "VtkCompositeFilter.h"
 
@@ -32,5 +31,3 @@ public:
 
 private:
 };
-
-#endif // VTKCOMPOSITECOLORMAPTOIMAGEFILTER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkCompositeContourFilter.h b/Applications/DataExplorer/VtkVis/VtkCompositeContourFilter.h
index 727bd7215d5..17349ba38af 100644
--- a/Applications/DataExplorer/VtkVis/VtkCompositeContourFilter.h
+++ b/Applications/DataExplorer/VtkVis/VtkCompositeContourFilter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKCOMPOSITECONTOURFILTER_H
-#define VTKCOMPOSITECONTOURFILTER_H
+#pragma once
 
 #include "VtkCompositeFilter.h"
 
@@ -34,5 +33,3 @@ public:
 
 private:
 };
-
-#endif // VTKCOMPOSITECONTOURFILTER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkCompositeElementSelectionFilter.h b/Applications/DataExplorer/VtkVis/VtkCompositeElementSelectionFilter.h
index 168ae997ab8..12c9901ba70 100644
--- a/Applications/DataExplorer/VtkVis/VtkCompositeElementSelectionFilter.h
+++ b/Applications/DataExplorer/VtkVis/VtkCompositeElementSelectionFilter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKCOMPOSITESELECTIONFILTER_H
-#define VTKCOMPOSITESELECTIONFILTER_H
+#pragma once
 
 #include "VtkCompositeFilter.h"
 
@@ -47,5 +46,3 @@ private:
     std::string _selection_name;
     std::vector<double> _selection;
 };
-
-#endif // VTKCOMPOSITESELECTIONFILTER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkCompositeFilter.h b/Applications/DataExplorer/VtkVis/VtkCompositeFilter.h
index 19e115fcfdd..d475240b919 100644
--- a/Applications/DataExplorer/VtkVis/VtkCompositeFilter.h
+++ b/Applications/DataExplorer/VtkVis/VtkCompositeFilter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKCOMPOSITEFILTER_H
-#define VTKCOMPOSITEFILTER_H
+#pragma once
 
 #include "VtkAlgorithmProperties.h"
 
@@ -80,5 +79,3 @@ protected:
 
     virtual void init() = 0;
 };
-
-#endif // VTKCOMPOSITEFILTER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkCompositeGeoObjectFilter.h b/Applications/DataExplorer/VtkVis/VtkCompositeGeoObjectFilter.h
index a4e8abd3067..ffada6a6653 100644
--- a/Applications/DataExplorer/VtkVis/VtkCompositeGeoObjectFilter.h
+++ b/Applications/DataExplorer/VtkVis/VtkCompositeGeoObjectFilter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKCOMPOSITEGEOOBJECTFILTER_H
-#define VTKCOMPOSITEGEOOBJECTFILTER_H
+#pragma once
 
 #include "VtkCompositeFilter.h"
 #include "GeoType.h"
@@ -42,5 +41,3 @@ private:
     GeoLib::GEOTYPE _type;
     vtkThreshold* _threshold;
 };
-
-#endif // VTKCOMPOSITEGEOOBJECTFILTER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkCompositeImageToCylindersFilter.h b/Applications/DataExplorer/VtkVis/VtkCompositeImageToCylindersFilter.h
index 595d96aacbf..53b73ec7c82 100644
--- a/Applications/DataExplorer/VtkVis/VtkCompositeImageToCylindersFilter.h
+++ b/Applications/DataExplorer/VtkVis/VtkCompositeImageToCylindersFilter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKCOMPOSITEIMAGETOCYLINDERSFILTER_H
-#define VTKCOMPOSITEIMAGETOCYLINDERSFILTER_H
+#pragma once
 
 #include "VtkCompositeFilter.h"
 
@@ -37,5 +36,3 @@ public:
 private:
     VtkImageDataToLinePolyDataFilter* _lineFilter;
 };
-
-#endif // VTKCOMPOSITEIMAGETOCYLINDERSFILTER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkCompositeLineToTubeFilter.h b/Applications/DataExplorer/VtkVis/VtkCompositeLineToTubeFilter.h
index 7b75246968d..68f4bae8ee6 100644
--- a/Applications/DataExplorer/VtkVis/VtkCompositeLineToTubeFilter.h
+++ b/Applications/DataExplorer/VtkVis/VtkCompositeLineToTubeFilter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKCOMPOSITELINETOTUBEFILTER_H
-#define VTKCOMPOSITELINETOTUBEFILTER_H
+#pragma once
 
 #include "VtkCompositeFilter.h"
 
@@ -31,5 +30,3 @@ public:
 private:
 
 };
-
-#endif // VTKCOMPOSITELINETOTUBEFILTER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkCompositeNodeSelectionFilter.h b/Applications/DataExplorer/VtkVis/VtkCompositeNodeSelectionFilter.h
index faca42688e1..d3dce1d7d43 100644
--- a/Applications/DataExplorer/VtkVis/VtkCompositeNodeSelectionFilter.h
+++ b/Applications/DataExplorer/VtkVis/VtkCompositeNodeSelectionFilter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKCOMPOSITENODESELECTIONFILTER_H
-#define VTKCOMPOSITENODESELECTIONFILTER_H
+#pragma once
 
 #include "VtkCompositeFilter.h"
 #include "Point.h"
@@ -35,5 +34,3 @@ public:
 private:
     std::vector<GeoLib::Point*> _selection;
 };
-
-#endif // VTKCOMPOSITENODESELECTIONFILTER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkCompositePointToGlyphFilter.h b/Applications/DataExplorer/VtkVis/VtkCompositePointToGlyphFilter.h
index cbb0f58f70b..4e277040a55 100644
--- a/Applications/DataExplorer/VtkVis/VtkCompositePointToGlyphFilter.h
+++ b/Applications/DataExplorer/VtkVis/VtkCompositePointToGlyphFilter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKCOMPOSITEPOINTTOGLYPHFILTER_H
-#define VTKCOMPOSITEPOINTTOGLYPHFILTER_H
+#pragma once
 
 #include "VtkCompositeFilter.h"
 
@@ -33,5 +32,3 @@ public:
 private:
     vtkSphereSource* _glyphSource;
 };
-
-#endif // VTKCOMPOSITEPOINTTOGLYPHFILTER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkCompositeTextureOnSurfaceFilter.h b/Applications/DataExplorer/VtkVis/VtkCompositeTextureOnSurfaceFilter.h
index b704418938c..98eef699b2e 100644
--- a/Applications/DataExplorer/VtkVis/VtkCompositeTextureOnSurfaceFilter.h
+++ b/Applications/DataExplorer/VtkVis/VtkCompositeTextureOnSurfaceFilter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKCOMPOSITETEXTUREONSURFACEFILTER_H
-#define VTKCOMPOSITETEXTUREONSURFACEFILTER_H
+#pragma once
 
 #include "VtkCompositeFilter.h"
 
@@ -32,5 +31,3 @@ public:
 
 private:
 };
-
-#endif // VTKCOMPOSITETEXTUREONSURFACEFILTER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkCompositeThresholdFilter.h b/Applications/DataExplorer/VtkVis/VtkCompositeThresholdFilter.h
index a5ca60c2ffd..0e7556a17c3 100644
--- a/Applications/DataExplorer/VtkVis/VtkCompositeThresholdFilter.h
+++ b/Applications/DataExplorer/VtkVis/VtkCompositeThresholdFilter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKCOMPOSITETHRESHOLDFILTER_H
-#define VTKCOMPOSITETHRESHOLDFILTER_H
+#pragma once
 
 #include "VtkCompositeFilter.h"
 
@@ -34,5 +33,3 @@ public:
 
 private:
 };
-
-#endif // VTKCOMPOSITETHRESHOLDFILTER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkConsoleOutputWindow.h b/Applications/DataExplorer/VtkVis/VtkConsoleOutputWindow.h
index d7012ce7c56..5cf19696cca 100644
--- a/Applications/DataExplorer/VtkVis/VtkConsoleOutputWindow.h
+++ b/Applications/DataExplorer/VtkVis/VtkConsoleOutputWindow.h
@@ -9,8 +9,7 @@
 *
 */
 
-#ifndef VTKCONSOLEOUTPUTWINDOW_H_
-#define VTKCONSOLEOUTPUTWINDOW_H_
+#pragma once
 
 #include "vtkOutputWindow.h"
 
@@ -34,5 +33,3 @@ private:
     VtkConsoleOutputWindow(const VtkConsoleOutputWindow &);  // Not implemented.
     void operator=(const VtkConsoleOutputWindow &);  // Not implemented.
 };
-
-#endif // VTKCONSOLEOUTPUTWINDOW_H_
diff --git a/Applications/DataExplorer/VtkVis/VtkFilterFactory.h b/Applications/DataExplorer/VtkVis/VtkFilterFactory.h
index 53d610773c0..0007ea077c5 100644
--- a/Applications/DataExplorer/VtkVis/VtkFilterFactory.h
+++ b/Applications/DataExplorer/VtkVis/VtkFilterFactory.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKFILTERFACTORY_H
-#define VTKFILTERFACTORY_H
+#pragma once
 
 #include <QString>
 #include <QVector>
@@ -93,5 +92,3 @@ struct VtkFilterInfo
     int inputDataObjectType;
     int outputDataObjectType;
 };
-
-#endif // VTKFILTERFACTORY_H
diff --git a/Applications/DataExplorer/VtkVis/VtkGeoImageSource.h b/Applications/DataExplorer/VtkVis/VtkGeoImageSource.h
index 6f9fb6c2825..93a72a95e72 100644
--- a/Applications/DataExplorer/VtkVis/VtkGeoImageSource.h
+++ b/Applications/DataExplorer/VtkVis/VtkGeoImageSource.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKGEOIMAGESOURCE_H
-#define VTKGEOIMAGESOURCE_H
+#pragma once
 
 #include "VtkAlgorithmProperties.h"
 #include <vtkSimpleImageToImageFilter.h>
@@ -77,5 +76,3 @@ private:
 
     double _x0, _y0, _z0, _spacing;
 };
-
-#endif // VTKGEOIMAGESOURCE_H
diff --git a/Applications/DataExplorer/VtkVis/VtkImageDataToLinePolyDataFilter.h b/Applications/DataExplorer/VtkVis/VtkImageDataToLinePolyDataFilter.h
index 7155829afe8..2cc7247e594 100644
--- a/Applications/DataExplorer/VtkVis/VtkImageDataToLinePolyDataFilter.h
+++ b/Applications/DataExplorer/VtkVis/VtkImageDataToLinePolyDataFilter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKIMAGEDATATOLINEPOLYDATAFILTER_H
-#define VTKIMAGEDATATOLINEPOLYDATAFILTER_H
+#pragma once
 
 #include "VtkAlgorithmProperties.h"
 #include <vtkPolyDataAlgorithm.h>
@@ -70,5 +69,3 @@ private:
     VtkImageDataToLinePolyDataFilter(const VtkImageDataToLinePolyDataFilter&); // Not implemented.
     void operator=(const VtkImageDataToLinePolyDataFilter&); // Not implemented
 };
-
-#endif // VTKIMAGEDATATOLINEPOLYDATAFILTER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkPointsSource.h b/Applications/DataExplorer/VtkVis/VtkPointsSource.h
index 640d5ade9bf..a9e50ddca50 100644
--- a/Applications/DataExplorer/VtkVis/VtkPointsSource.h
+++ b/Applications/DataExplorer/VtkVis/VtkPointsSource.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKPOINTSSOURCE_H
-#define VTKPOINTSSOURCE_H
+#pragma once
 
 // ** INCLUDES **
 #include "VtkAlgorithmProperties.h"
@@ -60,5 +59,3 @@ protected:
 
 private:
 };
-
-#endif // VTKPOINTSSOURCE_H
diff --git a/Applications/DataExplorer/VtkVis/VtkPolylinesSource.h b/Applications/DataExplorer/VtkVis/VtkPolylinesSource.h
index ff071cc83b0..b8e03bc8329 100644
--- a/Applications/DataExplorer/VtkVis/VtkPolylinesSource.h
+++ b/Applications/DataExplorer/VtkVis/VtkPolylinesSource.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKPOLYLINESSOURCE_H
-#define VTKPOLYLINESSOURCE_H
+#pragma once
 
 // ** INCLUDES **
 #include "VtkAlgorithmProperties.h"
@@ -63,5 +62,3 @@ protected:
 
 private:
 };
-
-#endif // VTKPOLYLINESSOURCE_H
diff --git a/Applications/DataExplorer/VtkVis/VtkRaster.h b/Applications/DataExplorer/VtkVis/VtkRaster.h
index bb7f1f92308..74a8fbcb857 100644
--- a/Applications/DataExplorer/VtkVis/VtkRaster.h
+++ b/Applications/DataExplorer/VtkVis/VtkRaster.h
@@ -11,8 +11,7 @@
  *              http://www.opengeosys.org/project/license
  *
  */
-#ifndef VTKRASTER_H
-#define VTKRASTER_H
+#pragma once
 
 #include <string>
 #include "GeoLib/Raster.h"
@@ -73,5 +72,3 @@ private:
     /// Converts an uint32-number into a quadruple representing RGBA-colours for a pixel.
     static void uint32toRGBA(const unsigned int s, int* p);
 };
-
-#endif //VTKRASTER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkStationSource.h b/Applications/DataExplorer/VtkVis/VtkStationSource.h
index 1f5417d506e..da7e5619840 100644
--- a/Applications/DataExplorer/VtkVis/VtkStationSource.h
+++ b/Applications/DataExplorer/VtkVis/VtkStationSource.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKSTATIONSOURCE_H
-#define VTKSTATIONSOURCE_H
+#pragma once
 
 #include <vtkPolyDataAlgorithm.h>
 
@@ -77,5 +76,3 @@ private:
 
     std::map<std::string, vtkIdType> _id_map;
 };
-
-#endif // VTKSTATIONSOURCE_H
diff --git a/Applications/DataExplorer/VtkVis/VtkSurfacesSource.h b/Applications/DataExplorer/VtkVis/VtkSurfacesSource.h
index c385ef495c1..f3b3b21e517 100644
--- a/Applications/DataExplorer/VtkVis/VtkSurfacesSource.h
+++ b/Applications/DataExplorer/VtkVis/VtkSurfacesSource.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKSURFACESSOURCE_H
-#define VTKSURFACESSOURCE_H
+#pragma once
 
 // ** INCLUDES **
 #include "VtkAlgorithmProperties.h"
@@ -64,5 +63,3 @@ protected:
 
 private:
 };
-
-#endif // VTKSURFACESSOURCE_H
diff --git a/Applications/DataExplorer/VtkVis/VtkTextureOnSurfaceFilter.h b/Applications/DataExplorer/VtkVis/VtkTextureOnSurfaceFilter.h
index 9298553589b..0fb02d095e2 100644
--- a/Applications/DataExplorer/VtkVis/VtkTextureOnSurfaceFilter.h
+++ b/Applications/DataExplorer/VtkVis/VtkTextureOnSurfaceFilter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKOGSPOLYDATAALGORITHM_H
-#define VTKOGSPOLYDATAALGORITHM_H
+#pragma once
 
 // ** INCLUDES **
 #include "VtkAlgorithmProperties.h"
@@ -65,5 +64,3 @@ private:
     std::pair<float, float> _origin;
     double _scalingFactor;
 };
-
-#endif // VTKOGSPOLYDATAALGORITHM_H
diff --git a/Applications/DataExplorer/VtkVis/VtkVisHelper.h b/Applications/DataExplorer/VtkVis/VtkVisHelper.h
index 8561fe593dc..1ba17e91039 100644
--- a/Applications/DataExplorer/VtkVis/VtkVisHelper.h
+++ b/Applications/DataExplorer/VtkVis/VtkVisHelper.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKVISHELPER_H
-#define VTKVISHELPER_H
+#pragma once
 
 class QImage;
 class vtkTexture;
@@ -31,5 +30,3 @@ public:
     /// @brief Converts a QImage-object into a vtkTexture-object
     static vtkTexture* QImageToVtkTexture(QImage &img);
 };
-
-#endif // VTKVISHELPER_H
diff --git a/Applications/DataExplorer/VtkVis/VtkVisImageItem.h b/Applications/DataExplorer/VtkVis/VtkVisImageItem.h
index d0f1bd91af1..e24a9098d94 100644
--- a/Applications/DataExplorer/VtkVis/VtkVisImageItem.h
+++ b/Applications/DataExplorer/VtkVis/VtkVisImageItem.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKVISIMAGEITEM_H
-#define VTKVISIMAGEITEM_H
+#pragma once
 
 // ** INCLUDES **
 #include "VtkVisPipelineItem.h"
@@ -64,5 +63,3 @@ protected:
 private:
     vtkImageChangeInformation* _transformFilter;
 };
-
-#endif // VTKVISIMAGEITEM_H
diff --git a/Applications/DataExplorer/VtkVis/VtkVisPipeline.h b/Applications/DataExplorer/VtkVis/VtkVisPipeline.h
index e3589de1a91..4c496755311 100644
--- a/Applications/DataExplorer/VtkVis/VtkVisPipeline.h
+++ b/Applications/DataExplorer/VtkVis/VtkVisPipeline.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKVISPIPELINE_H
-#define VTKVISPIPELINE_H
+#pragma once
 
 #include <QMap>
 #include <QVector>
@@ -149,5 +148,3 @@ signals:
     void vtkVisPipelineChanged() const;
     void itemSelected(const QModelIndex&) const;
 };
-
-#endif // VTKVISPIPELINE_H
diff --git a/Applications/DataExplorer/VtkVis/VtkVisPipelineItem.h b/Applications/DataExplorer/VtkVis/VtkVisPipelineItem.h
index 1a7ff3b53f3..e0393d886a0 100644
--- a/Applications/DataExplorer/VtkVis/VtkVisPipelineItem.h
+++ b/Applications/DataExplorer/VtkVis/VtkVisPipelineItem.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKVISPIPELINEITEM_H
-#define VTKVISPIPELINEITEM_H
+#pragma once
 
 // ** INCLUDES **
 #include "BuildInfo.h"
@@ -147,5 +146,3 @@ protected:
 
 private:
 };
-
-#endif // VTKVISPIPELINEITEM_H
diff --git a/Applications/DataExplorer/VtkVis/VtkVisPipelineView.h b/Applications/DataExplorer/VtkVis/VtkVisPipelineView.h
index 0b0228503c6..cf93faf6725 100644
--- a/Applications/DataExplorer/VtkVis/VtkVisPipelineView.h
+++ b/Applications/DataExplorer/VtkVis/VtkVisPipelineView.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKVISPIPELINEVIEW_H
-#define VTKVISPIPELINEVIEW_H
+#pragma once
 
 // ** INCLUDES **
 #include <QTreeView>
@@ -88,5 +87,3 @@ signals:
     void dataObjectSelected(vtkDataObject*);
     void meshAdded(MeshLib::Mesh*);
 };
-
-#endif // VTKVISPIPELINEVIEW_H
diff --git a/Applications/DataExplorer/VtkVis/VtkVisPointSetItem.h b/Applications/DataExplorer/VtkVis/VtkVisPointSetItem.h
index 8f9f4b95106..3c5e37d15ea 100644
--- a/Applications/DataExplorer/VtkVis/VtkVisPointSetItem.h
+++ b/Applications/DataExplorer/VtkVis/VtkVisPointSetItem.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTKVISPOINTSETITEM_H
-#define VTKVISPOINTSETITEM_H
+#pragma once
 
 // ** INCLUDES **
 #include "VtkVisPipelineItem.h"
@@ -95,5 +94,3 @@ private:
     bool activeAttributeExists(vtkDataSetAttributes* data, std::string& name);
 
 };
-
-#endif // VTKVISPOINTSETITEM_H
diff --git a/Applications/DataExplorer/VtkVis/VtkVisTabWidget.h b/Applications/DataExplorer/VtkVis/VtkVisTabWidget.h
index 6a935881614..d815a25ecc7 100644
--- a/Applications/DataExplorer/VtkVis/VtkVisTabWidget.h
+++ b/Applications/DataExplorer/VtkVis/VtkVisTabWidget.h
@@ -13,8 +13,7 @@
  *
  */
 
-#ifndef VTKVISTABWIDGET_H
-#define VTKVISTABWIDGET_H
+#pragma once
 
 // ** INCLUDES **
 #include "ui_VtkVisTabWidgetBase.h"
@@ -76,5 +75,3 @@ signals:
     /// Is emitted when a property was changed.
     void requestViewUpdate();
 };
-
-#endif // VTKVISTABWIDGET_H
diff --git a/Applications/DataExplorer/mainwindow.h b/Applications/DataExplorer/mainwindow.h
index c09d1294a44..e1fc2fb9153 100644
--- a/Applications/DataExplorer/mainwindow.h
+++ b/Applications/DataExplorer/mainwindow.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MAINWINDOW_H
-#define MAINWINDOW_H
+#pragma once
 
 #include <memory>
 
@@ -156,5 +155,3 @@ public:
         qapp->exec();
     }
 };
-
-#endif // MAINWINDOW_H
diff --git a/Applications/DataHolderLib/Color.h b/Applications/DataHolderLib/Color.h
index 07c421ef3aa..bce09bb8309 100644
--- a/Applications/DataHolderLib/Color.h
+++ b/Applications/DataHolderLib/Color.h
@@ -13,8 +13,7 @@
  *
  */
 
-#ifndef COLOR_H_
-#define COLOR_H_
+#pragma once
 
 #include <array>
 #include <map>
@@ -38,5 +37,3 @@ Color const getColor(const std::string &id, std::map<std::string, DataHolderLib:
 /// Convenience function to use the getColor method with numbers as identifiers.
 Color const getColor(double id, std::map<std::string, DataHolderLib::Color> &colors);
 } // namespace
-
-#endif /* COLOR_H_ */
diff --git a/Applications/DataHolderLib/ColorLookupTable.h b/Applications/DataHolderLib/ColorLookupTable.h
index da3e2970837..f71c178134c 100644
--- a/Applications/DataHolderLib/ColorLookupTable.h
+++ b/Applications/DataHolderLib/ColorLookupTable.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef COLORLOOKUPTABLE_H
-#define COLORLOOKUPTABLE_H
+#pragma once
 
 #include <cassert>
 #include <tuple>
@@ -67,5 +66,3 @@ private:
 };
 
 } // namespace
-
-#endif //COLORLOOKUPTABLE_H
diff --git a/Applications/DataHolderLib/Project.h b/Applications/DataHolderLib/Project.h
index 7f240e6a6aa..c3087039695 100644
--- a/Applications/DataHolderLib/Project.h
+++ b/Applications/DataHolderLib/Project.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef DATAEXPLORERPROJECT_H_
-#define DATAEXPLORERPROJECT_H_
+#pragma once
 
 #include <memory>
 
@@ -81,5 +80,3 @@ private:
 };
 
 } // namespace
-
-#endif //DATAEXPLORERPROJECT_H_
diff --git a/Applications/FileIO/AsciiRasterInterface.h b/Applications/FileIO/AsciiRasterInterface.h
index cf653a9f4e6..baa80fb9e17 100644
--- a/Applications/FileIO/AsciiRasterInterface.h
+++ b/Applications/FileIO/AsciiRasterInterface.h
@@ -11,8 +11,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef ASCIIRASTERINTERFACE_H_
-#define ASCIIRASTERINTERFACE_H_
+#pragma once
 
 #include <fstream>
 #include <vector>
@@ -57,5 +56,3 @@ private:
 boost::optional<std::vector<GeoLib::Raster const*>> readRasters(
     std::vector<std::string> const& raster_paths);
 } // end namespace FileIO
-
-#endif /* ASCIIRASTERINTERFACE_H_ */
diff --git a/Applications/FileIO/CsvInterface.h b/Applications/FileIO/CsvInterface.h
index cca9cdc2b4b..fe87228764e 100644
--- a/Applications/FileIO/CsvInterface.h
+++ b/Applications/FileIO/CsvInterface.h
@@ -11,8 +11,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef CSVINTERFACE_H_
-#define CSVINTERFACE_H_
+#pragma once
 
 #include <logog/include/logog.hpp>
 #include <boost/any.hpp>
@@ -240,5 +239,3 @@ private:
 };
 
 } // FileIO
-
-#endif /* CSVINTERFACE_H_ */
diff --git a/Applications/FileIO/FEFLOW/FEFLOWGeoInterface.h b/Applications/FileIO/FEFLOW/FEFLOWGeoInterface.h
index 2c9079b8a9b..e98aa410e64 100644
--- a/Applications/FileIO/FEFLOW/FEFLOWGeoInterface.h
+++ b/Applications/FileIO/FEFLOW/FEFLOWGeoInterface.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef FEFLOWGEOINTERFACE_H_
-#define FEFLOWGEOINTERFACE_H_
+#pragma once
 
 #include <iosfwd>
 #include <string>
@@ -57,5 +56,3 @@ private:
                            int dim, std::vector<GeoLib::Point*>& points);
 };
 }  // FileIO
-
-#endif /* FEFLOWGEOINTERFACE_H_ */
diff --git a/Applications/FileIO/FEFLOW/FEFLOWMeshInterface.h b/Applications/FileIO/FEFLOW/FEFLOWMeshInterface.h
index 82c21b89252..67d20008ff7 100644
--- a/Applications/FileIO/FEFLOW/FEFLOWMeshInterface.h
+++ b/Applications/FileIO/FEFLOW/FEFLOWMeshInterface.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef FEFLOWMESHINTERFACE_H_
-#define FEFLOWMESHINTERFACE_H_
+#pragma once
 
 #include <iosfwd>
 #include <string>
@@ -125,5 +124,3 @@ private:
         std::vector<int>& material_ids);
 };
 }  // FileIO
-
-#endif /* FEFLOWMESHINTERFACE_H_ */
diff --git a/Applications/FileIO/GMSInterface.h b/Applications/FileIO/GMSInterface.h
index 30f3a89cd4a..591ebd84569 100644
--- a/Applications/FileIO/GMSInterface.h
+++ b/Applications/FileIO/GMSInterface.h
@@ -15,8 +15,7 @@
  * @author Lars Bilke
  */
 
-#ifndef GMSINTERFACE_H_
-#define GMSINTERFACE_H_
+#pragma once
 
 #include <list>
 #include <string>
@@ -80,5 +79,3 @@ private:
 };
 
 }
-
-#endif /* GMSINTERFACE_H_ */
diff --git a/Applications/FileIO/Gmsh/GMSHAdaptiveMeshDensity.h b/Applications/FileIO/Gmsh/GMSHAdaptiveMeshDensity.h
index 410d4d94177..3b3680eff77 100644
--- a/Applications/FileIO/Gmsh/GMSHAdaptiveMeshDensity.h
+++ b/Applications/FileIO/Gmsh/GMSHAdaptiveMeshDensity.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef GMSHADAPTIVEMESHDENSITY_H_
-#define GMSHADAPTIVEMESHDENSITY_H_
+#pragma once
 
 #include "GMSHMeshDensityStrategy.h"
 
@@ -55,5 +54,3 @@ private:
 
 }
 } // end namespace FileIO
-
-#endif /* GMSHADAPTIVEMESHDENSITY_H_ */
diff --git a/Applications/FileIO/Gmsh/GMSHFixedMeshDensity.h b/Applications/FileIO/Gmsh/GMSHFixedMeshDensity.h
index d68b23a0981..fb4fb2bea08 100644
--- a/Applications/FileIO/Gmsh/GMSHFixedMeshDensity.h
+++ b/Applications/FileIO/Gmsh/GMSHFixedMeshDensity.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef GMSHFIXEDMESHDENSITY_H_
-#define GMSHFIXEDMESHDENSITY_H_
+#pragma once
 
 #include "GMSHMeshDensityStrategy.h"
 
@@ -33,5 +32,3 @@ private:
 
 }
 } // end namespace FileIO
-
-#endif /* GMSHFIXEDMESHDENSITY_H_ */
diff --git a/Applications/FileIO/Gmsh/GMSHInterface.h b/Applications/FileIO/Gmsh/GMSHInterface.h
index d687a893e1b..ef6a7dc5c59 100644
--- a/Applications/FileIO/Gmsh/GMSHInterface.h
+++ b/Applications/FileIO/Gmsh/GMSHInterface.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef GMSHINTERFACE_H_
-#define GMSHINTERFACE_H_
+#pragma once
 
 #include <iosfwd>
 
@@ -116,5 +115,3 @@ private:
 };
 } // end namespace GMSH
 } // end namespace FileIO
-
-#endif /* GMSHINTERFACE_H_ */
diff --git a/Applications/FileIO/Gmsh/GMSHLine.h b/Applications/FileIO/Gmsh/GMSHLine.h
index 58b9c36960b..994e5d861d6 100644
--- a/Applications/FileIO/Gmsh/GMSHLine.h
+++ b/Applications/FileIO/Gmsh/GMSHLine.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef GMSHLINE_H_
-#define GMSHLINE_H_
+#pragma once
 
 #include <iosfwd>
 
@@ -31,5 +30,3 @@ private:
 
 } // end namespace GMSH
 } // end namespace FileIO
-
-#endif /* GMSHLINE_H_ */
diff --git a/Applications/FileIO/Gmsh/GMSHLineLoop.h b/Applications/FileIO/Gmsh/GMSHLineLoop.h
index c5a0d064b72..1c156d4268a 100644
--- a/Applications/FileIO/Gmsh/GMSHLineLoop.h
+++ b/Applications/FileIO/Gmsh/GMSHLineLoop.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef GMSHLINELOOP_H_
-#define GMSHLINELOOP_H_
+#pragma once
 
 #include <vector>
 #include <iosfwd>
@@ -37,5 +36,3 @@ private:
 
 }  // end namespace GMSH
 }  // end namespace FileIO
-
-#endif /* GMSHLINELOOP_H_ */
diff --git a/Applications/FileIO/Gmsh/GMSHMeshDensityStrategy.h b/Applications/FileIO/Gmsh/GMSHMeshDensityStrategy.h
index 682e1de84a8..3b14475dabf 100644
--- a/Applications/FileIO/Gmsh/GMSHMeshDensityStrategy.h
+++ b/Applications/FileIO/Gmsh/GMSHMeshDensityStrategy.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef GMSHMESHDENSITYSTRATEGY_H_
-#define GMSHMESHDENSITYSTRATEGY_H_
+#pragma once
 
 #include <vector>
 
@@ -37,5 +36,3 @@ public:
 
 }  // end namespace GMSH
 }  // end namespace FileIO
-
-#endif /* GMSHMESHDENSITYSTRATEGY_H_ */
diff --git a/Applications/FileIO/Gmsh/GMSHPoint.h b/Applications/FileIO/Gmsh/GMSHPoint.h
index 4441b49f9c5..f1a4f11c1d9 100644
--- a/Applications/FileIO/Gmsh/GMSHPoint.h
+++ b/Applications/FileIO/Gmsh/GMSHPoint.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef GMSHPOINT_H_
-#define GMSHPOINT_H_
+#pragma once
 
 // GeoLib
 #include "GeoLib/Point.h"
@@ -32,5 +31,3 @@ std::ostream& operator<< (std::ostream &os, GMSHPoint const& p);
 
 }  // end namespace GMSH
 }  // end namespace FileIO
-
-#endif /* GMSHPOINT_H_ */
diff --git a/Applications/FileIO/Gmsh/GMSHPolygonTree.h b/Applications/FileIO/Gmsh/GMSHPolygonTree.h
index 2094bdd31f5..0ed605482b7 100644
--- a/Applications/FileIO/Gmsh/GMSHPolygonTree.h
+++ b/Applications/FileIO/Gmsh/GMSHPolygonTree.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef GMSHPOLYGONTREE_H_
-#define GMSHPOLYGONTREE_H_
+#pragma once
 
 #include <vector>
 #include <string>
@@ -102,5 +101,3 @@ private:
 
 }  // end namespace GMSH
 }  // end namespace FileIO
-
-#endif /* GMSHPOLYGONTREE_H_ */
diff --git a/Applications/FileIO/PetrelInterface.h b/Applications/FileIO/PetrelInterface.h
index 84618b8b96b..6c071df9c0b 100644
--- a/Applications/FileIO/PetrelInterface.h
+++ b/Applications/FileIO/PetrelInterface.h
@@ -15,8 +15,7 @@
  * @author Thomas Fischer
  */
 
-#ifndef PETRELIO_H_
-#define PETRELIO_H_
+#pragma once
 
 #include <iosfwd>
 #include <list>
@@ -51,5 +50,3 @@ private:
     static const std::size_t MAX_COLS_PER_ROW = 256;
 };
 } // end namespace FileIO
-
-#endif /* PETRELIO_H_ */
diff --git a/Applications/FileIO/SHPInterface.h b/Applications/FileIO/SHPInterface.h
index 14188b49ac8..4c484cfae0d 100644
--- a/Applications/FileIO/SHPInterface.h
+++ b/Applications/FileIO/SHPInterface.h
@@ -15,8 +15,7 @@
  * @author Karsten Rink
  */
 
-#ifndef SHPINTERFACE_H
-#define SHPINTERFACE_H
+#pragma once
 
 #include <string>
 #include <vector>
@@ -85,5 +84,3 @@ private:
 };
 
 }
-
-#endif //SHPINTERFACE_H
diff --git a/Applications/FileIO/SWMM/SWMMInterface.h b/Applications/FileIO/SWMM/SWMMInterface.h
index 8b050484ce3..da001e9d810 100644
--- a/Applications/FileIO/SWMM/SWMMInterface.h
+++ b/Applications/FileIO/SWMM/SWMMInterface.h
@@ -5,8 +5,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef SWMMINTERFACE_H_
-#define SWMMINTERFACE_H_
+#pragma once
 
 #include <map>
 #include <memory>
@@ -214,5 +213,3 @@ private:
 };
 
 } // namespace FileIO
-
-#endif // SWMMINTERFACE_H_
diff --git a/Applications/FileIO/TetGenInterface.h b/Applications/FileIO/TetGenInterface.h
index dd665b7fcae..05896a60b72 100644
--- a/Applications/FileIO/TetGenInterface.h
+++ b/Applications/FileIO/TetGenInterface.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef TETGENINTERFACE_H_
-#define TETGENINTERFACE_H_
+#pragma once
 
 #include <vector>
 
@@ -216,5 +215,3 @@ private:
     bool _boundary_markers;
 };
 }
-
-#endif /* TETGENINTERFACE_H_ */
diff --git a/Applications/FileIO/XmlIO/Qt/XmlGspInterface.h b/Applications/FileIO/XmlIO/Qt/XmlGspInterface.h
index a3fbb440695..720a1ad53a1 100644
--- a/Applications/FileIO/XmlIO/Qt/XmlGspInterface.h
+++ b/Applications/FileIO/XmlIO/Qt/XmlGspInterface.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef XMLGSPINTERFACE_H
-#define XMLGSPINTERFACE_H
+#pragma once
 
 #include <vector>
 #include <string>
@@ -56,5 +55,3 @@ private:
 };
 
 } // end namespace FileIO
-
-#endif // XMLGSPINTERFACE_H
diff --git a/Applications/FileIO/XmlIO/Qt/XmlLutReader.h b/Applications/FileIO/XmlIO/Qt/XmlLutReader.h
index 5cd3f7db7ea..2b52c964dd9 100644
--- a/Applications/FileIO/XmlIO/Qt/XmlLutReader.h
+++ b/Applications/FileIO/XmlIO/Qt/XmlLutReader.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef XMLLUTREADER_H
-#define XMLLUTREADER_H
+#pragma once
 
 #include <QFile>
 #include <QtXml/QDomDocument>
@@ -101,5 +100,3 @@ public:
 };
 
  }
-
-#endif // XMLLUTREADER_H
diff --git a/Applications/FileIO/XmlIO/Qt/XmlNumInterface.h b/Applications/FileIO/XmlIO/Qt/XmlNumInterface.h
index 25221d1b730..e4a10027469 100644
--- a/Applications/FileIO/XmlIO/Qt/XmlNumInterface.h
+++ b/Applications/FileIO/XmlIO/Qt/XmlNumInterface.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef XMLNUMINTERFACE_H
-#define XMLNUMINTERFACE_H
+#pragma once
 
 #include "BaseLib/IO/XmlIO/XMLInterface.h"
 #include "BaseLib/IO/XmlIO/Qt/XMLQtInterface.h"
@@ -41,5 +40,3 @@ protected:
 };
 
 }
-
-#endif // XMLNUMINTERFACE_H
diff --git a/Applications/Utils/ModelPreparation/PartitionMesh/NodeWiseMeshPartitioner.h b/Applications/Utils/ModelPreparation/PartitionMesh/NodeWiseMeshPartitioner.h
index 8666f0da852..c1505252263 100644
--- a/Applications/Utils/ModelPreparation/PartitionMesh/NodeWiseMeshPartitioner.h
+++ b/Applications/Utils/ModelPreparation/PartitionMesh/NodeWiseMeshPartitioner.h
@@ -12,8 +12,7 @@
 
 */
 
-#ifndef NODE_WISE_MESH_PARTITIONER_H_
-#define NODE_WISE_MESH_PARTITIONER_H_
+#pragma once
 
 #include <memory>
 #include <tuple>
@@ -192,5 +191,3 @@ private:
 };
 
 }  // namespace MeshLib
-
-#endif  // NODE_WISE_MESH_PARTITIONER_H_
diff --git a/Applications/Utils/OGSFileConverter/FileListDialog.h b/Applications/Utils/OGSFileConverter/FileListDialog.h
index a574dafc410..cfe7b079250 100644
--- a/Applications/Utils/OGSFileConverter/FileListDialog.h
+++ b/Applications/Utils/OGSFileConverter/FileListDialog.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef FILELISTDIALOG_H
-#define FILELISTDIALOG_H
+#pragma once
 
 #include "ui_FileList.h"
 #include <QDialog>
@@ -68,5 +67,3 @@ private slots:
     void reject();
 
 };
-
-#endif //FILELISTDIALOG_H
diff --git a/Applications/Utils/OGSFileConverter/OGSFileConverter.h b/Applications/Utils/OGSFileConverter/OGSFileConverter.h
index 92d24cc4d40..99f6ed02271 100644
--- a/Applications/Utils/OGSFileConverter/OGSFileConverter.h
+++ b/Applications/Utils/OGSFileConverter/OGSFileConverter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef OGSFILECONVERTER_H
-#define OGSFILECONVERTER_H
+#pragma once
 
 #include "ui_OGSFileConverter.h"
 #include <QDialog>
@@ -48,5 +47,3 @@ private slots:
     void on_msh2vtuButton_pressed() const;
     void on_closeDialogButton_pressed();
 };
-
-#endif //OGSFILECONVERTER_H
diff --git a/BaseLib/BuildInfo.h b/BaseLib/BuildInfo.h
index 95e412b1170..cc888557d63 100644
--- a/BaseLib/BuildInfo.h
+++ b/BaseLib/BuildInfo.h
@@ -9,8 +9,7 @@
  *
  */
 
-#ifndef BASE_LIB_BUILD_INFO_H_
-#define BASE_LIB_BUILD_INFO_H_
+#pragma once
 
 #include <string>
 
@@ -40,5 +39,3 @@ namespace BuildInfo
     extern const std::string tests_tmp_path;
 }
 }
-
-#endif  // BASE_LIB_BUILD_INFO_H_
diff --git a/BaseLib/CPUTime.h b/BaseLib/CPUTime.h
index cfaa2c8f80d..6905c4508c6 100644
--- a/BaseLib/CPUTime.h
+++ b/BaseLib/CPUTime.h
@@ -13,8 +13,7 @@
  *
  */
 
-#ifndef CPUTIME_H
-#define CPUTIME_H
+#pragma once
 
 #include <ctime>
 
@@ -41,6 +40,3 @@ class CPUTime
 };
 
 } // end namespace BaseLib
-
-#endif
-
diff --git a/BaseLib/CodingTools.h b/BaseLib/CodingTools.h
index aa3f3c76499..ddc930a1a12 100644
--- a/BaseLib/CodingTools.h
+++ b/BaseLib/CodingTools.h
@@ -12,11 +12,8 @@
  *
  */
 
-#ifndef CODINGTOOLS_H
-#define CODINGTOOLS_H
+#pragma once
 
 #define DISALLOW_COPY_AND_ASSIGN(TypeName) \
     TypeName(const TypeName&);   \
     TypeName &operator=(const TypeName&)
-
-#endif
diff --git a/BaseLib/ConfigTree.h b/BaseLib/ConfigTree.h
index 5ca4a062068..8f8bcc20fb0 100644
--- a/BaseLib/ConfigTree.h
+++ b/BaseLib/ConfigTree.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef BASELIB_CONFIGTREE_H_
-#define BASELIB_CONFIGTREE_H_
+#pragma once
 
 #include <typeindex>
 #include <map>
@@ -645,7 +644,3 @@ private:
 }
 
 #include "ConfigTree-impl.h"
-
-
-#endif // BASELIB_CONFIGTREE_H_
-
diff --git a/BaseLib/ConfigTreeUtil.h b/BaseLib/ConfigTreeUtil.h
index e783fc2ec8b..17d80e7760b 100644
--- a/BaseLib/ConfigTreeUtil.h
+++ b/BaseLib/ConfigTreeUtil.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef BASELIB_CONFIGTREEUTIL
-#define BASELIB_CONFIGTREEUTIL
+#pragma once
 
 #include "ConfigTree.h"
 
@@ -89,5 +88,3 @@ makeConfigTree(std::string const& filepath, bool const be_ruthless,
                std::string const& toplevel_tag);
 
 }
-
-#endif
diff --git a/BaseLib/Counter.h b/BaseLib/Counter.h
index 355ee838433..63524281375 100644
--- a/BaseLib/Counter.h
+++ b/BaseLib/Counter.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef BASELIB_GLOBALCOUNTER_H
-#define BASELIB_GLOBALCOUNTER_H
+#pragma once
 
 #include <cstddef>
 
@@ -27,5 +26,3 @@ struct Counter
 template <typename X> std::size_t Counter<X>::_counter_value(0);
 
 } // end namespace BaseLib
-
-#endif  // BASELIB_GLOBALCOUNTER_H
diff --git a/BaseLib/DateTools.h b/BaseLib/DateTools.h
index d9cf93510ff..783b60d611a 100644
--- a/BaseLib/DateTools.h
+++ b/BaseLib/DateTools.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef DATETOOLS_H
-#define DATETOOLS_H
+#pragma once
 
 #include <chrono>
 #include <string>
@@ -67,5 +66,3 @@ std::string formatDate(
     std::chrono::time_point<std::chrono::system_clock> const& time);
 
 } // namespace BaseLib
-
-#endif //DATETOOLS_H
diff --git a/BaseLib/DebugTools.h b/BaseLib/DebugTools.h
index f2695c1648c..1d20d528af3 100644
--- a/BaseLib/DebugTools.h
+++ b/BaseLib/DebugTools.h
@@ -11,8 +11,7 @@
  *
  */
 
-#ifndef DEBUGTOOLS_H
-#define DEBUGTOOLS_H
+#pragma once
 
 #include <ostream>
 #include <algorithm>
@@ -24,6 +23,3 @@ std::ostream &operator <<(std::ostream &os, const std::vector<T> &v) {
     os << "\n";
     return os;
 }
-
-#endif //DEBUGTOOLS_H
-
diff --git a/BaseLib/Error.h b/BaseLib/Error.h
index c418204d4cd..517c051bca2 100644
--- a/BaseLib/Error.h
+++ b/BaseLib/Error.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef BASELIB_ERROR_H
-#define BASELIB_ERROR_H
+#pragma once
 
 #ifdef OGS_FATAL_ABORT
 
@@ -36,5 +35,3 @@
     throw std::runtime_error(BaseLib::format(fmt, ##__VA_ARGS__) + OGS_LOCATION);
 
 #endif // OGS_FATAL_ABORT
-
-#endif //BASELIB_ERROR_H
diff --git a/BaseLib/FileFinder.h b/BaseLib/FileFinder.h
index f9a8fee7d18..02c412aa2d7 100644
--- a/BaseLib/FileFinder.h
+++ b/BaseLib/FileFinder.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef FILEFINDER_H
-#define FILEFINDER_H
+#pragma once
 
 #include <initializer_list>
 #include <string>
@@ -57,5 +56,3 @@ private:
     std::vector<std::string> _directories;
 };
 } // end namespace BaseLib
-
-#endif // FILEFINDER_H
diff --git a/BaseLib/FileTools.h b/BaseLib/FileTools.h
index 920864b2b5b..c4cb8e6f77e 100644
--- a/BaseLib/FileTools.h
+++ b/BaseLib/FileTools.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef FILETOOLS_H
-#define FILETOOLS_H
+#pragma once
 
 #include <fstream>
 #include <string>
@@ -163,5 +162,3 @@ std::string appendPathSeparator(std::string const& path);
 std::string joinPaths(std::string const& pathA, std::string const& pathB);
 
 } // end namespace BaseLib
-
-#endif // FILETOOLS_H
diff --git a/BaseLib/Functional.h b/BaseLib/Functional.h
index 55b4b453a51..000a2c9e5f8 100644
--- a/BaseLib/Functional.h
+++ b/BaseLib/Functional.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef BASELIB_FUNCTIONAL_H
-#define BASELIB_FUNCTIONAL_H
+#pragma once
 
 #include <functional>
 #include "BaseLib/TMPUtil.h"
@@ -212,5 +211,3 @@ typename detail::FunctionTraits<Object>::FunctionType easyBind(Object&& obj)
 }
 
 }  // namespace BaseLib
-
-#endif  // BASELIB_FUNCTIONAL_H
diff --git a/BaseLib/Histogram.h b/BaseLib/Histogram.h
index 88218b7b835..5c7155a896f 100644
--- a/BaseLib/Histogram.h
+++ b/BaseLib/Histogram.h
@@ -10,8 +10,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef BASELIB_HISTOGRAM_H
-#define BASELIB_HISTOGRAM_H
+#pragma once
 
 #include <algorithm>
 #include <cmath>
@@ -196,5 +195,3 @@ operator<<(std::ostream& os, const Histogram<T>& h)
     return os << std::endl;
 }
 }   // namespace BaseLib
-
-#endif  // BASELIB_HISTOGRAM_H
diff --git a/BaseLib/IO/Writer.h b/BaseLib/IO/Writer.h
index a1c7f3db743..0dabb332349 100644
--- a/BaseLib/IO/Writer.h
+++ b/BaseLib/IO/Writer.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef WRITER_H
-#define WRITER_H
+#pragma once
 
 #include <string>
 #include <sstream>
@@ -62,5 +61,3 @@ private:
 
 } // namespace IO
 } // namespace BaseLib
-
-#endif // WRITER_H
diff --git a/BaseLib/IO/XmlIO/Qt/XMLQtInterface.h b/BaseLib/IO/XmlIO/Qt/XMLQtInterface.h
index 2e85768f9ba..e290c064339 100644
--- a/BaseLib/IO/XmlIO/Qt/XMLQtInterface.h
+++ b/BaseLib/IO/XmlIO/Qt/XMLQtInterface.h
@@ -10,8 +10,7 @@
  *              See accompanying file LICENSE.txt or
  *              http://www.opengeosys.org/LICENSE.txt
  */
-#ifndef XMLQTINTERFACE_H_
-#define XMLQTINTERFACE_H_
+#pragma once
 
 #include <string>
 
@@ -64,5 +63,3 @@ protected:
 
 } // end namespace IO
 } // end namespace BaseLib
-
-#endif /* XMLQTINTERFACE_H_ */
diff --git a/BaseLib/IO/XmlIO/XMLInterface.h b/BaseLib/IO/XmlIO/XMLInterface.h
index 5f8a4d499d7..d8c8cbb9870 100644
--- a/BaseLib/IO/XmlIO/XMLInterface.h
+++ b/BaseLib/IO/XmlIO/XMLInterface.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef XMLINTERFACE_H
-#define XMLINTERFACE_H
+#pragma once
 
 #include <string>
 
@@ -41,5 +40,3 @@ protected:
 
 }
 }
-
-#endif // XMLINTERFACE_H
diff --git a/BaseLib/LogogCustomCout.h b/BaseLib/LogogCustomCout.h
index 19903bb0287..750a4e2513d 100644
--- a/BaseLib/LogogCustomCout.h
+++ b/BaseLib/LogogCustomCout.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef LOGOGCUSTOMCOUT_H_
-#define LOGOGCUSTOMCOUT_H_
+#pragma once
 
 #include <ostream>
 
@@ -66,6 +65,4 @@ private:
 #endif
 };
 
-#endif // LOGOGCUSTOMCOUT_H_
-
 } // namespace BaseLib
diff --git a/BaseLib/LogogSimpleFormatter.h b/BaseLib/LogogSimpleFormatter.h
index c805a1c4f5e..eeaab28468e 100644
--- a/BaseLib/LogogSimpleFormatter.h
+++ b/BaseLib/LogogSimpleFormatter.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef LOGOGSIMPLEFORMATTER_H
-#define LOGOGSIMPLEFORMATTER_H
+#pragma once
 
 #include <logog/include/logog.hpp>
 
@@ -34,5 +33,3 @@ class LogogSimpleFormatter : public logog::FormatterMSVC
 };
 
 }  // namespace BaseLib
-
-#endif  // LOGOGSIMPLEFORMATTER_H
diff --git a/BaseLib/MemWatch.h b/BaseLib/MemWatch.h
index 3afd3fcd471..cfbb92d8818 100644
--- a/BaseLib/MemWatch.h
+++ b/BaseLib/MemWatch.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MEMWATCH_H_
-#define MEMWATCH_H_
+#pragma once
 
 namespace BaseLib {
 
@@ -34,5 +33,3 @@ private:
 };
 
 }
-
-#endif /* MEMWATCH_H_ */
diff --git a/BaseLib/RunTime.h b/BaseLib/RunTime.h
index 91ead6496cc..197ec678baf 100644
--- a/BaseLib/RunTime.h
+++ b/BaseLib/RunTime.h
@@ -13,8 +13,7 @@
  *
  */
 
-#ifndef RUNTIME_H
-#define RUNTIME_H
+#pragma once
 
 #if defined(USE_MPI)
 #include <mpi.h>
@@ -70,5 +69,3 @@ class RunTime
 };
 
 } // end namespace BaseLib
-
-#endif
diff --git a/BaseLib/StringTools.h b/BaseLib/StringTools.h
index 4138e36053a..7702d794a5f 100644
--- a/BaseLib/StringTools.h
+++ b/BaseLib/StringTools.h
@@ -12,9 +12,7 @@
  *
  */
 
-#ifndef STRINGTOOLS_H
-#define STRINGTOOLS_H
-
+#pragma once
 
 #include <string>
 #include <list>
@@ -96,5 +94,3 @@ std::string format(const char* format_string, ... );
 #ifdef MSVC
 void correctScientificNotation(std::string filename, std::size_t precision = 0);
 #endif
-
-#endif //STRINGTOOLS_H
diff --git a/BaseLib/Subdivision.h b/BaseLib/Subdivision.h
index 370b308a93c..dbfa4c576e0 100644
--- a/BaseLib/Subdivision.h
+++ b/BaseLib/Subdivision.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef SUBDIVISION_H_
-#define SUBDIVISION_H_
+#pragma once
 
 #include <cmath>
 
@@ -108,5 +107,3 @@ private:
 };
 
 } // BaseLib
-
-#endif /* SUBDIVISION_H_ */
diff --git a/BaseLib/TCLAPCustomOutput.h b/BaseLib/TCLAPCustomOutput.h
index 20b3daa186f..dea0f3c0070 100644
--- a/BaseLib/TCLAPCustomOutput.h
+++ b/BaseLib/TCLAPCustomOutput.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef TCLAPCUSTOMOUTPUT_H_
-#define TCLAPCUSTOMOUTPUT_H_
+#pragma once
 
 #include <string>
 #include <vector>
@@ -179,6 +178,3 @@ TCLAPCustomOutput::_longUsage( TCLAP::CmdLineInterface& _cmd,
 }
 
 } //namespace BaseLib
-
-#endif /* TCLAPCUSTOMOUTPUT_H_ */
-
diff --git a/BaseLib/TMPUtil.h b/BaseLib/TMPUtil.h
index 5297bea5ed9..1b0d8fdb0a3 100644
--- a/BaseLib/TMPUtil.h
+++ b/BaseLib/TMPUtil.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef BASELIB_TMPUTIL_H
-#define BASELIB_TMPUTIL_H
+#pragma once
 
 namespace BaseLib
 {
@@ -42,5 +41,3 @@ struct GenerateIntegerSequence<0, S...> {
  */
 
 }  // namespace BaseLib
-
-#endif  // BASELIB_TMPUTIL_H
diff --git a/BaseLib/TemplateLogogFormatterSuppressedGCC.h b/BaseLib/TemplateLogogFormatterSuppressedGCC.h
index 7e4d736cb57..52730d867da 100644
--- a/BaseLib/TemplateLogogFormatterSuppressedGCC.h
+++ b/BaseLib/TemplateLogogFormatterSuppressedGCC.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef TEMPLATELOGOGFORMATTERSUPPRESSEDGCC_H_
-#define TEMPLATELOGOGFORMATTERSUPPRESSEDGCC_H_
+#pragma once
 
 #include <string>
 
@@ -56,5 +55,3 @@ private:
 } // namespace BaseLib
 
 #include "TemplateLogogFormatterSuppressedGCC-impl.h"
-
-#endif // TEMPLATELOGOGFORMATTERSUPPRESSEDGCC_H_
diff --git a/BaseLib/excludeObjectCopy.h b/BaseLib/excludeObjectCopy.h
index d8dc41fce75..65fed57969a 100644
--- a/BaseLib/excludeObjectCopy.h
+++ b/BaseLib/excludeObjectCopy.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef EXCLUDEOBJECTCOPIER_H_
-#define EXCLUDEOBJECTCOPIER_H_
+#pragma once
 
 #include <vector>
 #include <algorithm>
@@ -61,6 +60,3 @@ void excludeObjectCopy(std::vector<T> const& src_vec,
 
 
 } // end namespace BaseLib
-
-#endif
-
diff --git a/BaseLib/makeVectorUnique.h b/BaseLib/makeVectorUnique.h
index 7efbb1251a0..cc6bf7ae27a 100644
--- a/BaseLib/makeVectorUnique.h
+++ b/BaseLib/makeVectorUnique.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef MAKEVECTORUNIQUE_H
-#define MAKEVECTORUNIQUE_H
+#pragma once
 
 #include <algorithm>
 #include <vector>
@@ -38,4 +37,3 @@ void makeVectorUnique(std::vector<T>& v, Compare comp)
 }
 
 } // end namespace BaseLib
-#endif
diff --git a/BaseLib/quicksort.h b/BaseLib/quicksort.h
index 02960b98c3f..a5f0e9905ce 100644
--- a/BaseLib/quicksort.h
+++ b/BaseLib/quicksort.h
@@ -9,8 +9,7 @@
  *
  */
 
-#ifndef QUICKSORT_H_
-#define QUICKSORT_H_
+#pragma once
 
 #include <algorithm>
 #include <cassert>
@@ -95,5 +94,3 @@ void quicksort(std::vector<T1*>& array, std::size_t beg, std::size_t end, std::v
 }
 
 } // end namespace BaseLib
-
-#endif /* QUICKSORT_H_ */
diff --git a/BaseLib/reorderVector.h b/BaseLib/reorderVector.h
index e6dfbac62bb..230cf6ee107 100644
--- a/BaseLib/reorderVector.h
+++ b/BaseLib/reorderVector.h
@@ -11,8 +11,7 @@
  * Created on October 13, 2016, 5:37 PM
  */
 
-#ifndef OGS_BASELIB_REORDERVECTOR_H
-#define OGS_BASELIB_REORDERVECTOR_H
+#pragma once
 
 namespace BaseLib
 {
@@ -35,5 +34,3 @@ void reorderVector(std::vector<ValueType>& v,
 }
 
 } // end of namespace
-#endif /* OGS_BASELIB_REORDERVECTOR_H */
-
diff --git a/BaseLib/uniqueInsert.h b/BaseLib/uniqueInsert.h
index e7b4c2693d0..25aa7e28479 100644
--- a/BaseLib/uniqueInsert.h
+++ b/BaseLib/uniqueInsert.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef UNIQUELISTINSERT_H_
-#define UNIQUELISTINSERT_H_
+#pragma once
 
 #include <algorithm>
 
@@ -99,5 +98,3 @@ getOrError(
 }
 
 } // end namespace BaseLib
-
-#endif /* UNIQUELISTINSERT_H_ */
diff --git a/GeoLib/AABB.h b/GeoLib/AABB.h
index 617c838a49e..4abf643ff39 100644
--- a/GeoLib/AABB.h
+++ b/GeoLib/AABB.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef AABB_H_
-#define AABB_H_
+#pragma once
 
 #include <bitset>
 #include <cassert>
@@ -246,5 +245,3 @@ private:
     }
 };
 } // end namespace
-
-#endif /* AABB_H_ */
diff --git a/GeoLib/AnalyticalGeometry.h b/GeoLib/AnalyticalGeometry.h
index 99d8ac0e0f3..6a2d544a069 100644
--- a/GeoLib/AnalyticalGeometry.h
+++ b/GeoLib/AnalyticalGeometry.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef ANALYTICAL_GEOMETRY_H_
-#define ANALYTICAL_GEOMETRY_H_
+#pragma once
 
 #include <memory>
 
@@ -260,5 +259,3 @@ void sortSegments(MathLib::Point3d const& seg_beg_pnt,
 } // end namespace GeoLib
 
 #include "AnalyticalGeometry-impl.h"
-
-#endif /* ANALYTICAL_GEOMETRY_H_ */
diff --git a/GeoLib/ClosestPair.h b/GeoLib/ClosestPair.h
index a7ea954ab48..33c4f4b799b 100644
--- a/GeoLib/ClosestPair.h
+++ b/GeoLib/ClosestPair.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef CLOSESTPAIR_H_
-#define CLOSESTPAIR_H_
+#pragma once
 
 // STL
 #include <vector>
@@ -37,5 +36,3 @@ protected:
 };
 
 } // end namespace GeoLib
-
-#endif /* CLOSESTPAIR_H_ */
diff --git a/GeoLib/DuplicateGeometry.h b/GeoLib/DuplicateGeometry.h
index d501028e835..820f09a3df5 100644
--- a/GeoLib/DuplicateGeometry.h
+++ b/GeoLib/DuplicateGeometry.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef DUPLICATEGEOMETRY_H_
-#define DUPLICATEGEOMETRY_H_
+#pragma once
 
 #include <memory>
 #include <string>
@@ -65,5 +64,3 @@ private:
 }; // class
 
 } // namespace
-
-#endif /* DUPLICATEGEOMETRY_H_ */
diff --git a/GeoLib/EarClippingTriangulation.h b/GeoLib/EarClippingTriangulation.h
index ad097ad156b..839887766bd 100644
--- a/GeoLib/EarClippingTriangulation.h
+++ b/GeoLib/EarClippingTriangulation.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef EARCLIPPINGTRIANGULATION_H_
-#define EARCLIPPINGTRIANGULATION_H_
+#pragma once
 
 #include <list>
 #include <vector>
@@ -62,5 +61,3 @@ private:
     GeoLib::Orientation _original_orient;
 };
 } // end namespace GeoLib
-
-#endif /* EARCLIPPINGTRIANGULATION_H_ */
diff --git a/GeoLib/GEOObjects.h b/GeoLib/GEOObjects.h
index 5bec7f7398a..911ec685c72 100644
--- a/GeoLib/GEOObjects.h
+++ b/GeoLib/GEOObjects.h
@@ -11,8 +11,7 @@
  *
  */
 
-#ifndef GEOOBJECTS_H_
-#define GEOOBJECTS_H_
+#pragma once
 
 #include <map>
 #include <functional>
@@ -352,5 +351,3 @@ private:
             std::string & merged_geo_name, std::vector<std::size_t> const& pnt_offsets);
 };
 } // end namespace
-
-#endif /* GEOOBJECTS_H_ */
diff --git a/GeoLib/GeoObject.h b/GeoLib/GeoObject.h
index 21952b4717c..0fd6caac36b 100644
--- a/GeoLib/GeoObject.h
+++ b/GeoLib/GeoObject.h
@@ -13,8 +13,7 @@
  *
  */
 
-#ifndef GEOOBJECT_H_
-#define GEOOBJECT_H_
+#pragma once
 
 #include "GeoType.h"
 
@@ -31,5 +30,3 @@ public:
     virtual GEOTYPE getGeoType() const = 0;
 };
 } // end namespace GeoLib
-
-#endif /* GEOOBJECT_H_ */
diff --git a/GeoLib/GeoType.h b/GeoLib/GeoType.h
index 8a61ff9ab47..0051fc33956 100644
--- a/GeoLib/GeoType.h
+++ b/GeoLib/GeoType.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef GEOTYPE_H_
-#define GEOTYPE_H_
+#pragma once
 
 #include <string>
 
@@ -32,5 +31,3 @@ enum class GEOTYPE {
 std::string convertGeoTypeToString (GEOTYPE geo_type);
 
 } // end namespace GeoLib
-
-#endif /* GEOTYPE_H_ */
diff --git a/GeoLib/Grid.h b/GeoLib/Grid.h
index 43f8c6f5d9d..fba64e6089b 100644
--- a/GeoLib/Grid.h
+++ b/GeoLib/Grid.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef GRID_H_
-#define GRID_H_
+#pragma once
 
 #include <bitset>
 #include <vector>
@@ -603,5 +602,3 @@ Grid<POINT>::getPointsInEpsilonEnvironment(P const& pnt, double eps) const
 }
 
 } // end namespace GeoLib
-
-#endif /* MESHGRID_H_ */
diff --git a/GeoLib/IO/Legacy/OGSIOVer4.h b/GeoLib/IO/Legacy/OGSIOVer4.h
index 2a369aea39a..8e1f9ab992b 100644
--- a/GeoLib/IO/Legacy/OGSIOVer4.h
+++ b/GeoLib/IO/Legacy/OGSIOVer4.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef OGSIOVER4_H_
-#define OGSIOVER4_H_
+#pragma once
 
 #include <string>
 #include <vector>
@@ -45,5 +44,3 @@ void writeAllDataToGLIFileV4 (const std::string& fname, const GeoLib::GEOObjects
 }
 } // end namespace IO
 } // end namespace GeoLib
-
-#endif /* OGSIOVER4_H_ */
diff --git a/GeoLib/IO/TINInterface.h b/GeoLib/IO/TINInterface.h
index 850d74a80f3..51962fe2f80 100644
--- a/GeoLib/IO/TINInterface.h
+++ b/GeoLib/IO/TINInterface.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef TININTERFACE_H_
-#define TININTERFACE_H_
+#pragma once
 
 #include <string>
 #include <vector>
@@ -49,5 +48,3 @@ public:
 
 } // end namespace IO
 } // end namespace GeoLib
-
-#endif /* TININTERFACE_H_ */
diff --git a/GeoLib/IO/XmlIO/Boost/BoostXmlGmlInterface.h b/GeoLib/IO/XmlIO/Boost/BoostXmlGmlInterface.h
index e6ea4aa7f50..9e478ba4285 100644
--- a/GeoLib/IO/XmlIO/Boost/BoostXmlGmlInterface.h
+++ b/GeoLib/IO/XmlIO/Boost/BoostXmlGmlInterface.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef BOOSTXMLGMLINTERFACE_H_
-#define BOOSTXMLGMLINTERFACE_H_
+#pragma once
 
 #include <map>
 #include <string>
@@ -75,5 +74,3 @@ private:
 
 } // end namespace IO
 } // end namespace GeoLib
-
-#endif /* BOOSTXMLGMLINTERFACE_H_ */
diff --git a/GeoLib/IO/XmlIO/Qt/XmlGmlInterface.h b/GeoLib/IO/XmlIO/Qt/XmlGmlInterface.h
index 92abf6943d3..1f41bb3d948 100644
--- a/GeoLib/IO/XmlIO/Qt/XmlGmlInterface.h
+++ b/GeoLib/IO/XmlIO/Qt/XmlGmlInterface.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef XMLGMLINTERFACE_H
-#define XMLGMLINTERFACE_H
+#pragma once
 
 #include <QString>
 
@@ -90,5 +89,3 @@ private:
 
 } // end namespace IO
 } // end namespace BaseLib
-
-#endif // XMLGMLINTERFACE_H
diff --git a/GeoLib/IO/XmlIO/Qt/XmlStnInterface.h b/GeoLib/IO/XmlIO/Qt/XmlStnInterface.h
index 6f2372a50ad..c9e0bff0d8d 100644
--- a/GeoLib/IO/XmlIO/Qt/XmlStnInterface.h
+++ b/GeoLib/IO/XmlIO/Qt/XmlStnInterface.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef XMLSTNINTERFACE_H
-#define XMLSTNINTERFACE_H
+#pragma once
 
 #include <vector>
 
@@ -73,5 +72,3 @@ private:
 
 } // end namespace IO
 } // end namespace GeoLib
-
-#endif // XMLSTNINTERFACE_H
diff --git a/GeoLib/IO/XmlIO/Rapid/RapidStnInterface.h b/GeoLib/IO/XmlIO/Rapid/RapidStnInterface.h
index 70a32ae5d38..0bf24f40c46 100644
--- a/GeoLib/IO/XmlIO/Rapid/RapidStnInterface.h
+++ b/GeoLib/IO/XmlIO/Rapid/RapidStnInterface.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef RAPIDXMLINTERFACE_H
-#define RAPIDXMLINTERFACE_H
+#pragma once
 
 #include <string>
 #include <vector>
@@ -51,5 +50,3 @@ private:
 
 } // IO
 } // GeoLib
-
-#endif // RAPIDXMLINTERFACE_H
diff --git a/GeoLib/IO/readGeometryFromFile.h b/GeoLib/IO/readGeometryFromFile.h
index 584b9aea2bf..15c40fdccd4 100644
--- a/GeoLib/IO/readGeometryFromFile.h
+++ b/GeoLib/IO/readGeometryFromFile.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef READGEOMETRYFROMFILE_H
-#define READGEOMETRYFROMFILE_H
+#pragma once
 
 #include <string>
 
@@ -26,5 +25,3 @@ namespace IO
     readGeometryFromFile(std::string const& fname, GeoLib::GEOObjects & geo_objs);
 }
 }
-
-#endif // READGEOMETRYFROMFILE_H
diff --git a/GeoLib/IO/writeGeometryToFile.h b/GeoLib/IO/writeGeometryToFile.h
index ab1da24cdc8..a669cee45bc 100644
--- a/GeoLib/IO/writeGeometryToFile.h
+++ b/GeoLib/IO/writeGeometryToFile.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef WRITEGEOMETRYTOFILE_H
-#define WRITEGEOMETRYTOFILE_H
+#pragma once
 
 #include <string>
 
@@ -28,5 +27,3 @@ void writeGeometryToFile(std::string const& geo_name,
     GeoLib::GEOObjects& geo_objs, std::string const& fname);
 }
 }
-
-#endif // WRITEGEOMETRYTOFILE_H
diff --git a/GeoLib/LineSegment.h b/GeoLib/LineSegment.h
index 76800a06339..bb04e127c49 100644
--- a/GeoLib/LineSegment.h
+++ b/GeoLib/LineSegment.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef LINESEGMENT_H_
-#define LINESEGMENT_H_
+#pragma once
 
 #include "Point.h"
 
@@ -60,4 +59,3 @@ std::ostream& operator<<(std::ostream& os,
 bool operator==(LineSegment const& s0, LineSegment const& s1);
 
 }
-#endif
diff --git a/GeoLib/MinimalBoundingSphere.h b/GeoLib/MinimalBoundingSphere.h
index d23882e6e75..b16b5e2d2f2 100644
--- a/GeoLib/MinimalBoundingSphere.h
+++ b/GeoLib/MinimalBoundingSphere.h
@@ -13,8 +13,7 @@
  *
  */
 
-#ifndef MINIMALBOUNDINGSPHERE_H_
-#define MINIMALBOUNDINGSPHERE_H_
+#pragma once
 
 #include <vector>
 
@@ -86,5 +85,3 @@ private:
 };
 
 } // namespace
-
-#endif /* MINIMALBOUNDINGSPHERE_H_ */
diff --git a/GeoLib/OctTree.h b/GeoLib/OctTree.h
index ad9c32491ff..54dde3f2de1 100644
--- a/GeoLib/OctTree.h
+++ b/GeoLib/OctTree.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef OCTTREE_H_
-#define OCTTREE_H_
+#pragma once
 
 #include <cstdint>
 
@@ -149,5 +148,3 @@ private:
 } // end namespace GeoLib
 
 #include "OctTree-impl.h"
-
-#endif /* OCTTREE_H_ */
diff --git a/GeoLib/Point.h b/GeoLib/Point.h
index 0645e91af06..3d61d4ee2b1 100644
--- a/GeoLib/Point.h
+++ b/GeoLib/Point.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef POINT_H_
-#define POINT_H_
+#pragma once
 
 // GeoLib
 #include "GeoObject.h"
@@ -62,6 +61,3 @@ protected:
 };
 
 }
-
-#endif /* POINT_H_ */
-
diff --git a/GeoLib/PointVec.h b/GeoLib/PointVec.h
index d382ac1628d..3c26bf00750 100644
--- a/GeoLib/PointVec.h
+++ b/GeoLib/PointVec.h
@@ -22,8 +22,7 @@
 #include <string>
 #include <vector>
 
-#ifndef POINTVEC_H_
-#define POINTVEC_H_
+#pragma once
 
 #include "TemplateVec.h"
 #include "OctTree.h"
@@ -146,5 +145,3 @@ private:
     std::unique_ptr<GeoLib::OctTree<GeoLib::Point, 16>> _oct_tree;
 };
 } // end namespace
-
-#endif /* POINTVEC_H_ */
diff --git a/GeoLib/Polygon.h b/GeoLib/Polygon.h
index 617304ff918..08a7267f4b8 100644
--- a/GeoLib/Polygon.h
+++ b/GeoLib/Polygon.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef POLYGON_H_
-#define POLYGON_H_
+#pragma once
 
 #include <list>
 #include <vector>
@@ -167,5 +166,3 @@ GeoLib::Polygon* createPolygonFromCircle (GeoLib::Point const& middle_pnt,
 bool operator==(Polygon const& lhs, Polygon const& rhs);
 
 } // end namespace GeoLib
-
-#endif /* POLYGON_H_ */
diff --git a/GeoLib/PolygonWithSegmentMarker.h b/GeoLib/PolygonWithSegmentMarker.h
index b61ad2830b3..6d91c215ad8 100644
--- a/GeoLib/PolygonWithSegmentMarker.h
+++ b/GeoLib/PolygonWithSegmentMarker.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef POLYGONWITHSEGMENTMARKER_H_
-#define POLYGONWITHSEGMENTMARKER_H_
+#pragma once
 
 #include "Polygon.h"
 
@@ -53,5 +52,3 @@ private:
 };
 
 } // end namespace GeoLib
-
-#endif /* POLYGONWITHSEGMENTMARKER_H_ */
diff --git a/GeoLib/Polyline.h b/GeoLib/Polyline.h
index 72fc6ce30c7..5113d1e085f 100644
--- a/GeoLib/Polyline.h
+++ b/GeoLib/Polyline.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef POLYLINE_H_
-#define POLYLINE_H_
+#pragma once
 
 #include <cmath>
 #include <vector>
@@ -264,5 +263,3 @@ bool operator==(Polyline const& lhs, Polyline const& rhs);
 bool pointsAreIdentical(const std::vector<Point*> &pnt_vec, std::size_t i, std::size_t j,
                         double prox);
 } // end namespace
-
-#endif /* POLYLINE_H_ */
diff --git a/GeoLib/PolylineVec.h b/GeoLib/PolylineVec.h
index 2e73fb3b1db..cd09252f3ae 100644
--- a/GeoLib/PolylineVec.h
+++ b/GeoLib/PolylineVec.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef POLYLINEVEC_H_
-#define POLYLINEVEC_H_
+#pragma once
 
 #include "TemplateVec.h"
 #include "Polyline.h"
@@ -30,5 +29,3 @@ namespace GeoLib {
 typedef TemplateVec<Polyline> PolylineVec;
 
 } // end namespace
-
-#endif /* POLYLINEVEC_H_ */
diff --git a/GeoLib/PolylineWithSegmentMarker.h b/GeoLib/PolylineWithSegmentMarker.h
index f5e794a2c04..a7f72b4da0d 100644
--- a/GeoLib/PolylineWithSegmentMarker.h
+++ b/GeoLib/PolylineWithSegmentMarker.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef POLYLINEWITHSEGMENTMARKER_H_
-#define POLYLINEWITHSEGMENTMARKER_H_
+#pragma once
 
 #include "Polyline.h"
 
@@ -59,5 +58,3 @@ private:
 };
 
 }
-
-#endif /* POLYLINEWITHSEGMENTMARKER_H_ */
diff --git a/GeoLib/QuadTree.h b/GeoLib/QuadTree.h
index 37d90748c7b..de71d952ef1 100644
--- a/GeoLib/QuadTree.h
+++ b/GeoLib/QuadTree.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef QUADTREE_H_
-#define QUADTREE_H_
+#pragma once
 
 #include <limits>
 
@@ -494,5 +493,3 @@ private:
     const std::size_t _max_points_per_leaf;
 };
 }
-
-#endif /* QUADTREE_H_ */
diff --git a/GeoLib/Raster.h b/GeoLib/Raster.h
index a69a44a3db1..386ab2ecb59 100644
--- a/GeoLib/Raster.h
+++ b/GeoLib/Raster.h
@@ -11,8 +11,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef RASTER_H_
-#define RASTER_H_
+#pragma once
 
 #include "Surface.h"
 
@@ -105,5 +104,3 @@ private:
 };
 
 }
-
-#endif /* RASTER_H_ */
diff --git a/GeoLib/SensorData.h b/GeoLib/SensorData.h
index c5050e055c5..b8ec6186fe3 100644
--- a/GeoLib/SensorData.h
+++ b/GeoLib/SensorData.h
@@ -12,9 +12,7 @@
  *
  */
 
-
-#ifndef SENSORDATA_H
-#define SENSORDATA_H
+#pragma once
 
 #include <cstddef>
 #include <string>
@@ -130,6 +128,3 @@ private:
     std::vector< std::vector<float>* > _data_vecs;
 
 };
-
-#endif //SENSORDATA_H
-
diff --git a/GeoLib/SimplePolygonTree.h b/GeoLib/SimplePolygonTree.h
index f7f581174d6..eb53dd8a786 100644
--- a/GeoLib/SimplePolygonTree.h
+++ b/GeoLib/SimplePolygonTree.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef SIMPLEPOLYGONTREE_H_
-#define SIMPLEPOLYGONTREE_H_
+#pragma once
 
 #include <list>
 
@@ -110,5 +109,3 @@ void createPolygonTrees (std::list<POLYGONTREETYPE*>& list_of_simple_polygon_hie
 
 
 } // end namespace GeoLib
-
-#endif /* SIMPLEPOLYGONTREE_H_ */
diff --git a/GeoLib/Station.h b/GeoLib/Station.h
index e720d014b50..adca976c61b 100644
--- a/GeoLib/Station.h
+++ b/GeoLib/Station.h
@@ -12,9 +12,7 @@
  *
  */
 
-
-#ifndef GEO_STATION_H
-#define GEO_STATION_H
+#pragma once
 
 #include <string>
 
@@ -107,5 +105,3 @@ private:
 
 bool isStation(GeoLib::Point const* pnt);
 } // namespace
-
-#endif // GEO_STATION_H
diff --git a/GeoLib/StationBorehole.h b/GeoLib/StationBorehole.h
index 05e9252faf2..725d62c80f6 100644
--- a/GeoLib/StationBorehole.h
+++ b/GeoLib/StationBorehole.h
@@ -12,9 +12,7 @@
  *
  */
 
-
-#ifndef GEO_STATIONBOREHOLE_H
-#define GEO_STATIONBOREHOLE_H
+#pragma once
 
 #include "Station.h"
 
@@ -120,5 +118,3 @@ private:
 bool isBorehole(GeoLib::Point const* pnt);
 
 } // namespace
-
-#endif // GEO_STATIONBOREHOLE_H
diff --git a/GeoLib/Surface.h b/GeoLib/Surface.h
index fcf24f7e2fd..0dccba5e65b 100644
--- a/GeoLib/Surface.h
+++ b/GeoLib/Surface.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef SURFACE_H_
-#define SURFACE_H_
+#pragma once
 
 #include <vector>
 #include <memory>
@@ -104,5 +103,3 @@ protected:
     mutable std::unique_ptr<SurfaceGrid> _surface_grid;
 };
 }
-
-#endif /* SURFACE_H_ */
diff --git a/GeoLib/SurfaceGrid.h b/GeoLib/SurfaceGrid.h
index 85741eb6054..55cc76cd85e 100644
--- a/GeoLib/SurfaceGrid.h
+++ b/GeoLib/SurfaceGrid.h
@@ -9,8 +9,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef SURFACEGRID_H_
-#define SURFACEGRID_H_
+#pragma once
 
 #include <array>
 #include <limits>
@@ -45,5 +44,3 @@ private:
 };
 
 } // end namespace GeoLib
-
-#endif /* SURFACEGRID_H_ */
diff --git a/GeoLib/SurfaceVec.h b/GeoLib/SurfaceVec.h
index b14bcf78128..abd452a3a83 100644
--- a/GeoLib/SurfaceVec.h
+++ b/GeoLib/SurfaceVec.h
@@ -12,9 +12,7 @@
  *
  */
 
-
-#ifndef SURFACEVEC_H_
-#define SURFACEVEC_H_
+#pragma once
 
 #include "TemplateVec.h"
 #include "Surface.h"
@@ -29,5 +27,3 @@ namespace GeoLib {
 typedef TemplateVec<Surface> SurfaceVec;
 
 } // end namespace
-
-#endif /* SURFACEVEC_H_ */
diff --git a/GeoLib/TemplateVec.h b/GeoLib/TemplateVec.h
index f2263aea19f..36a0ba2ab4c 100644
--- a/GeoLib/TemplateVec.h
+++ b/GeoLib/TemplateVec.h
@@ -13,8 +13,7 @@
  *
  */
 
-#ifndef TEMPLATEVEC_H_
-#define TEMPLATEVEC_H_
+#pragma once
 
 #include <algorithm>
 #include <cstdlib>
@@ -238,5 +237,3 @@ protected:
     NameIdMap* _name_id_map;
 };
 } // end namespace GeoLib
-
-#endif /* TEMPLATEVEC_H_ */
diff --git a/GeoLib/Triangle.h b/GeoLib/Triangle.h
index 0baeaa07ce5..9ed82555ac7 100644
--- a/GeoLib/Triangle.h
+++ b/GeoLib/Triangle.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef TRIANGLE_H_
-#define TRIANGLE_H_
+#pragma once
 
 #include <vector>
 
@@ -87,5 +86,3 @@ private:
 void getPlaneCoefficients(Triangle const& tri, double c[3]);
 
 } // end namespace GeoLib
-
-#endif /* TRIANGLE_H_ */
diff --git a/MaterialLib/Adsorption/Adsorption.h b/MaterialLib/Adsorption/Adsorption.h
index ca780a62469..685d6bbfc41 100644
--- a/MaterialLib/Adsorption/Adsorption.h
+++ b/MaterialLib/Adsorption/Adsorption.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef ADSORPTION_H
-#define ADSORPTION_H
+#pragma once
 
 #include <array>
 #include <cmath>
@@ -82,5 +81,3 @@ inline double dCurvePolyfrac(const double* coeffs, const double x)
 }
 
 }
-
-#endif // ADSORPTION_H
diff --git a/MaterialLib/Adsorption/Density100MPa.h b/MaterialLib/Adsorption/Density100MPa.h
index 2d9f80dcf1d..ecd5d099abf 100644
--- a/MaterialLib/Adsorption/Density100MPa.h
+++ b/MaterialLib/Adsorption/Density100MPa.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALSLIB_ADSORPTION_DENSITY100MPA_H
-#define MATERIALSLIB_ADSORPTION_DENSITY100MPA_H
+#pragma once
 
 #include "Adsorption.h"
 
@@ -25,4 +24,3 @@ public:
 };
 
 }
-#endif // MATERIALSLIB_ADSORPTION_DENSITY100MPA_H
diff --git a/MaterialLib/Adsorption/DensityConst.h b/MaterialLib/Adsorption/DensityConst.h
index ee78332e22d..97a20104426 100644
--- a/MaterialLib/Adsorption/DensityConst.h
+++ b/MaterialLib/Adsorption/DensityConst.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALSLIB_ADSORPTION_DENSITYCONST_H
-#define MATERIALSLIB_ADSORPTION_DENSITYCONST_H
+#pragma once
 
 #include "Adsorption.h"
 
@@ -25,4 +24,3 @@ public:
 };
 
 }
-#endif // MATERIALSLIB_ADSORPTION_DENSITYCONST_H
diff --git a/MaterialLib/Adsorption/DensityCook.h b/MaterialLib/Adsorption/DensityCook.h
index 268bfc87e4b..35722161f6c 100644
--- a/MaterialLib/Adsorption/DensityCook.h
+++ b/MaterialLib/Adsorption/DensityCook.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALSLIB_ADSORPTION_DENSITYCOOK_H
-#define MATERIALSLIB_ADSORPTION_DENSITYCOOK_H
+#pragma once
 
 #include "Adsorption.h"
 
@@ -54,4 +53,3 @@ inline double alphaTWaterDean(const double T_Ads)
 }
 
 }
-#endif // MATERIALSLIB_ADSORPTION_DENSITYCOOK_H
diff --git a/MaterialLib/Adsorption/DensityDubinin.h b/MaterialLib/Adsorption/DensityDubinin.h
index 84747caffa9..a66bb696bb8 100644
--- a/MaterialLib/Adsorption/DensityDubinin.h
+++ b/MaterialLib/Adsorption/DensityDubinin.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALSLIB_ADSORPTION_DENSITYDUBININ_H
-#define MATERIALSLIB_ADSORPTION_DENSITYDUBININ_H
+#pragma once
 
 #include "Adsorption.h"
 
@@ -25,4 +24,3 @@ public:
 };
 
 }
-#endif // MATERIALSLIB_ADSORPTION_DENSITYDUBININ_H
diff --git a/MaterialLib/Adsorption/DensityHauer.h b/MaterialLib/Adsorption/DensityHauer.h
index 518e415aca7..1bf9d1995c5 100644
--- a/MaterialLib/Adsorption/DensityHauer.h
+++ b/MaterialLib/Adsorption/DensityHauer.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALSLIB_ADSORPTION_DENSITYHAUER_H
-#define MATERIALSLIB_ADSORPTION_DENSITYHAUER_H
+#pragma once
 
 #include "Adsorption.h"
 #include "DensityCook.h"
@@ -34,4 +33,3 @@ inline double rhoWaterHauer(const double T_Ads)
 }
 
 }
-#endif // MATERIALSLIB_ADSORPTION_DENSITYHAUER_H
diff --git a/MaterialLib/Adsorption/DensityLegacy.h b/MaterialLib/Adsorption/DensityLegacy.h
index 9fa67e62668..b75632a8393 100644
--- a/MaterialLib/Adsorption/DensityLegacy.h
+++ b/MaterialLib/Adsorption/DensityLegacy.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALSLIB_ADSORPTION_DENSITYLEGACY_H
-#define MATERIALSLIB_ADSORPTION_DENSITYLEGACY_H
+#pragma once
 
 #include "Adsorption.h"
 
@@ -25,4 +24,3 @@ public:
 };
 
 }
-#endif // MATERIALSLIB_ADSORPTION_DENSITYLEGACY_H
diff --git a/MaterialLib/Adsorption/DensityMette.h b/MaterialLib/Adsorption/DensityMette.h
index 3e27f43f365..0ec144f1f57 100644
--- a/MaterialLib/Adsorption/DensityMette.h
+++ b/MaterialLib/Adsorption/DensityMette.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALSLIB_ADSORPTION_DENSITYMETTE_H
-#define MATERIALSLIB_ADSORPTION_DENSITYMETTE_H
+#pragma once
 
 #include "Adsorption.h"
 
@@ -25,4 +24,3 @@ public:
 };
 
 }
-#endif // MATERIALSLIB_ADSORPTION_DENSITYMETTE_H
diff --git a/MaterialLib/Adsorption/DensityNunez.h b/MaterialLib/Adsorption/DensityNunez.h
index 78b9ad69e39..7e4e4e71b88 100644
--- a/MaterialLib/Adsorption/DensityNunez.h
+++ b/MaterialLib/Adsorption/DensityNunez.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALSLIB_ADSORPTION_DENSITYNUNEZ_H
-#define MATERIALSLIB_ADSORPTION_DENSITYNUNEZ_H
+#pragma once
 
 #include "Adsorption.h"
 
@@ -25,4 +24,3 @@ public:
 };
 
 }
-#endif // MATERIALSLIB_ADSORPTION_DENSITYNUNEZ_H
diff --git a/MaterialLib/Adsorption/Reaction.h b/MaterialLib/Adsorption/Reaction.h
index 004b03110e9..2c0a157a6ce 100644
--- a/MaterialLib/Adsorption/Reaction.h
+++ b/MaterialLib/Adsorption/Reaction.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALSLIB_ADSORPTION_REACTION_H
-#define MATERIALSLIB_ADSORPTION_REACTION_H
+#pragma once
 
 #include <memory>
 
@@ -35,4 +34,3 @@ public:
 };
 
 }
-#endif // MATERIALSLIB_ADSORPTION_REACTION_H
diff --git a/MaterialLib/Adsorption/ReactionCaOH2.h b/MaterialLib/Adsorption/ReactionCaOH2.h
index 4cc7543eee3..16cbc79efd8 100644
--- a/MaterialLib/Adsorption/ReactionCaOH2.h
+++ b/MaterialLib/Adsorption/ReactionCaOH2.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALSLIB_ADSORPTION_REACTIONCAOH2_H
-#define MATERIALSLIB_ADSORPTION_REACTIONCAOH2_H
+#pragma once
 
 #include "BaseLib/ConfigTree.h"
 #include "Reaction.h"
@@ -84,4 +83,3 @@ public:
 };
 
 }
-#endif // MATERIALSLIB_ADSORPTION_REACTIONCAOH2_H
diff --git a/MaterialLib/Adsorption/ReactionInert.h b/MaterialLib/Adsorption/ReactionInert.h
index bc49787fb08..3e3a05052c1 100644
--- a/MaterialLib/Adsorption/ReactionInert.h
+++ b/MaterialLib/Adsorption/ReactionInert.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALSLIB_ADSORPTION_REACTIONINERT_H
-#define MATERIALSLIB_ADSORPTION_REACTIONINERT_H
+#pragma once
 
 #include "BaseLib/Error.h"
 
@@ -34,4 +33,3 @@ public:
 };
 
 }
-#endif // MATERIALSLIB_ADSORPTION_REACTIONINERT_H
diff --git a/MaterialLib/Adsorption/ReactionSinusoidal.h b/MaterialLib/Adsorption/ReactionSinusoidal.h
index 6f40dd2d46c..00179611a1c 100644
--- a/MaterialLib/Adsorption/ReactionSinusoidal.h
+++ b/MaterialLib/Adsorption/ReactionSinusoidal.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALSLIB_ADSORPTION_REACTIONSINUSOIDAL_H
-#define MATERIALSLIB_ADSORPTION_REACTIONSINUSOIDAL_H
+#pragma once
 
 #include <logog/include/logog.hpp>
 
@@ -45,4 +44,3 @@ private:
 };
 
 }
-#endif // MATERIALSLIB_ADSORPTION_REACTIONSINUSOIDAL_H
diff --git a/MaterialLib/Fluid/ConstantFluidProperty.h b/MaterialLib/Fluid/ConstantFluidProperty.h
index 48528004074..d3ddc608374 100644
--- a/MaterialLib/Fluid/ConstantFluidProperty.h
+++ b/MaterialLib/Fluid/ConstantFluidProperty.h
@@ -10,8 +10,7 @@
  * Created on August 15, 2016, 12:11 PM
  */
 
-#ifndef CONSTANTFLUIDPROPERTY_H
-#define CONSTANTFLUIDPROPERTY_H
+#pragma once
 
 #include "FluidProperty.h"
 
@@ -57,4 +56,3 @@ private:
 
 }  // end namespace
 }  // end namespace
-#endif /* CONSTANTFLUIDPROPERTY_H */
diff --git a/MaterialLib/Fluid/Density/IdealGasLaw.h b/MaterialLib/Fluid/Density/IdealGasLaw.h
index f8925d1f97e..5445f439f5d 100644
--- a/MaterialLib/Fluid/Density/IdealGasLaw.h
+++ b/MaterialLib/Fluid/Density/IdealGasLaw.h
@@ -12,8 +12,7 @@
                See accompanying file LICENSE.txt or
                http://www.opengeosys.org/project/license
  */
-#ifndef IDEAL_GAS_LAW_H_
-#define IDEAL_GAS_LAW_H_
+#pragma once
 
 #include <cassert>
 #include <string>
@@ -90,4 +89,3 @@ private:
 };
 }  // end namespace
 }  // end namespace
-#endif
diff --git a/MaterialLib/Fluid/Density/LinearTemperatureDependentDensity.h b/MaterialLib/Fluid/Density/LinearTemperatureDependentDensity.h
index 75b29615ab8..3d7327d5607 100644
--- a/MaterialLib/Fluid/Density/LinearTemperatureDependentDensity.h
+++ b/MaterialLib/Fluid/Density/LinearTemperatureDependentDensity.h
@@ -11,8 +11,7 @@
  * Created on August 10, 2016, 11:34 AM
  */
 
-#ifndef LINEARTEMPERATUREDEPENDENTDENSITY_H
-#define LINEARTEMPERATUREDEPENDENTDENSITY_H
+#pragma once
 
 #include <string>
 
@@ -74,5 +73,3 @@ private:
 
 }  // end namespace
 }  // end namespace
-
-#endif /* LINEARTEMPERATUREDEPENDENTDENSITY_H */
diff --git a/MaterialLib/Fluid/Density/LiquidDensity.h b/MaterialLib/Fluid/Density/LiquidDensity.h
index f55bc9041ad..5bfd617fff9 100644
--- a/MaterialLib/Fluid/Density/LiquidDensity.h
+++ b/MaterialLib/Fluid/Density/LiquidDensity.h
@@ -11,8 +11,7 @@
  * Created on August 4, 2016, 10:15 AM
  */
 
-#ifndef LIQUIDDENSITY_H
-#define LIQUIDDENSITY_H
+#pragma once
 
 #include <vector>
 
@@ -141,5 +140,3 @@ private:
 
 }  // end of namespace
 }  // end of namespace
-
-#endif /* LIQUIDDENSITY_H */
diff --git a/MaterialLib/Fluid/Density/WaterDensityIAPWSIF97Region1.h b/MaterialLib/Fluid/Density/WaterDensityIAPWSIF97Region1.h
index a658fd6dfbd..ff2dbbe088c 100644
--- a/MaterialLib/Fluid/Density/WaterDensityIAPWSIF97Region1.h
+++ b/MaterialLib/Fluid/Density/WaterDensityIAPWSIF97Region1.h
@@ -10,8 +10,7 @@
  * Created on December 8, 2016, 4:19 PM
  */
 
-#ifndef OGS_WATER_DENSITY_IAPWSIF97_REGION1_H
-#define OGS_WATER_DENSITY_IAPWSIF97_REGION1_H
+#pragma once
 
 #include <string>
 
@@ -93,4 +92,3 @@ private:
 
 }  // end of namespace
 }  // end of namespace
-#endif /* OGS_WATER_DENSITY_IAPWSIF97_REGION1_H */
diff --git a/MaterialLib/Fluid/Density/createFluidDensityModel.h b/MaterialLib/Fluid/Density/createFluidDensityModel.h
index e6c08a1061c..df3e7fb9057 100644
--- a/MaterialLib/Fluid/Density/createFluidDensityModel.h
+++ b/MaterialLib/Fluid/Density/createFluidDensityModel.h
@@ -8,8 +8,7 @@
                See accompanying file LICENSE.txt or
                http://www.opengeosys.org/project/license
 */
-#ifndef CREATE_FLUID_DENSITY_MODEL_H_
-#define CREATE_FLUID_DENSITY_MODEL_H_
+#pragma once
 
 #include <memory>
 
@@ -27,4 +26,3 @@ std::unique_ptr<FluidProperty> createFluidDensityModel(
     BaseLib::ConfigTree const& config);
 }
 }  // end namespace
-#endif
diff --git a/MaterialLib/Fluid/FluidProperty.h b/MaterialLib/Fluid/FluidProperty.h
index cf2cdd292c3..ec3af66e9f7 100644
--- a/MaterialLib/Fluid/FluidProperty.h
+++ b/MaterialLib/Fluid/FluidProperty.h
@@ -10,8 +10,7 @@
  * Created on August 12, 2016, 3:34 PM
  */
 
-#ifndef FLUIDPROPERTY_H
-#define FLUIDPROPERTY_H
+#pragma once
 
 #include <array>
 #include <string>
@@ -58,5 +57,3 @@ public:
 
 }  // end namespace
 }  // end namespace
-
-#endif /* FLUIDPROPERTY_H */
diff --git a/MaterialLib/Fluid/FluidPropertyHeaders.h b/MaterialLib/Fluid/FluidPropertyHeaders.h
index 111f5c84302..da18197b86e 100644
--- a/MaterialLib/Fluid/FluidPropertyHeaders.h
+++ b/MaterialLib/Fluid/FluidPropertyHeaders.h
@@ -11,10 +11,7 @@
  * Created on August 18, 2016, 11:10 AM
  */
 
-#ifndef FLUIDPROPERTYHEADERS_H
-#define FLUIDPROPERTYHEADERS_H
+#pragma once
 
 #include "Density/createFluidDensityModel.h"
 #include "Viscosity/createViscosityModel.h"
-
-#endif /* FLUIDPROPERTYHEADERS_H */
diff --git a/MaterialLib/Fluid/GibbsFreeEnergy/DimensionLessGibbsFreeEnergyRegion1.h b/MaterialLib/Fluid/GibbsFreeEnergy/DimensionLessGibbsFreeEnergyRegion1.h
index f8b1f143e30..0b32f47d3ad 100644
--- a/MaterialLib/Fluid/GibbsFreeEnergy/DimensionLessGibbsFreeEnergyRegion1.h
+++ b/MaterialLib/Fluid/GibbsFreeEnergy/DimensionLessGibbsFreeEnergyRegion1.h
@@ -12,8 +12,7 @@
  * Created on December 8, 2016, 12:31 PM
  */
 
-#ifndef OGS_DIMENSION_LESS_GIBBS_FREE_ENERGY_REGION1_H
-#define OGS_DIMENSION_LESS_GIBBS_FREE_ENERGY_REGION1_H
+#pragma once
 
 namespace MaterialLib
 {
@@ -97,4 +96,3 @@ public:
 
 }  // end namespace
 }  // end namespace
-#endif /* OGS_DIMENSION_LESS_GIBBS_FREE_ENERGY_REGION1_H */
diff --git a/MaterialLib/Fluid/Viscosity/LinearPressureDependentViscosity.h b/MaterialLib/Fluid/Viscosity/LinearPressureDependentViscosity.h
index 29d560925ea..0b4dc08e840 100644
--- a/MaterialLib/Fluid/Viscosity/LinearPressureDependentViscosity.h
+++ b/MaterialLib/Fluid/Viscosity/LinearPressureDependentViscosity.h
@@ -9,8 +9,7 @@
  *
  *   \file  LinearPressureDependentViscosity.h
  */
-#ifndef LINEAR_PRESSURE_DEPENDENT_VISCOSITY_H_
-#define LINEAR_PRESSURE_DEPENDENT_VISCOSITY_H_
+#pragma once
 
 #include <string>
 
@@ -85,4 +84,3 @@ private:
 
 }  // end namespace
 }  // end namespace
-#endif
diff --git a/MaterialLib/Fluid/Viscosity/TemperatureDependentViscosity.h b/MaterialLib/Fluid/Viscosity/TemperatureDependentViscosity.h
index 0af468d58cb..fc65e398011 100644
--- a/MaterialLib/Fluid/Viscosity/TemperatureDependentViscosity.h
+++ b/MaterialLib/Fluid/Viscosity/TemperatureDependentViscosity.h
@@ -12,8 +12,7 @@
  *  Created on August 10, 2016, 10:45 AM
  */
 
-#ifndef TEMPERATUREDEPENDENTVISCOSITY_H
-#define TEMPERATUREDEPENDENTVISCOSITY_H
+#pragma once
 
 #include <string>
 #include <cmath>
@@ -93,5 +92,3 @@ private:
 
 }  // end namespace
 }  // end namespace
-
-#endif /* TEMPERATUREDEPENDENTVISCOSITY_H */
diff --git a/MaterialLib/Fluid/Viscosity/VogelsLiquidDynamicViscosity.h b/MaterialLib/Fluid/Viscosity/VogelsLiquidDynamicViscosity.h
index 44e490ef8db..ed94b0fb825 100644
--- a/MaterialLib/Fluid/Viscosity/VogelsLiquidDynamicViscosity.h
+++ b/MaterialLib/Fluid/Viscosity/VogelsLiquidDynamicViscosity.h
@@ -11,8 +11,7 @@
  *
  */
 
-#ifndef VOGELS_LIQUID_DYNAMIC_VISCOSITY_H_
-#define VOGELS_LIQUID_DYNAMIC_VISCOSITY_H_
+#pragma once
 
 #include <string>
 #include <vector>
@@ -112,4 +111,3 @@ struct VogelsViscosityConstantsCH4
 
 }  // end namespace
 }  // end namespace
-#endif
diff --git a/MaterialLib/Fluid/Viscosity/WaterViscosityIAPWS.h b/MaterialLib/Fluid/Viscosity/WaterViscosityIAPWS.h
index 918eddafa79..356383bb120 100644
--- a/MaterialLib/Fluid/Viscosity/WaterViscosityIAPWS.h
+++ b/MaterialLib/Fluid/Viscosity/WaterViscosityIAPWS.h
@@ -14,8 +14,7 @@
  * Created on December 1, 2016, 1:41 PM
  */
 
-#ifndef OGS_WATER_VISCOSITY_IAPWS_H
-#define OGS_WATER_VISCOSITY_IAPWS_H
+#pragma once
 
 #include <string>
 
@@ -85,5 +84,3 @@ private:
 
 }  // end namespace
 }  // end namespace
-
-#endif /* OGS_WATER_VISCOSITY_IAPWS_H */
diff --git a/MaterialLib/Fluid/Viscosity/createViscosityModel.h b/MaterialLib/Fluid/Viscosity/createViscosityModel.h
index dd4f972aa71..f39dd57a06f 100644
--- a/MaterialLib/Fluid/Viscosity/createViscosityModel.h
+++ b/MaterialLib/Fluid/Viscosity/createViscosityModel.h
@@ -11,8 +11,7 @@
  *
  */
 
-#ifndef CREATE_VISCOSITY_MODEL_H_
-#define CREATE_VISCOSITY_MODEL_H_
+#pragma once
 
 #include <memory>
 
@@ -31,4 +30,3 @@ std::unique_ptr<FluidProperty> createViscosityModel(
 
 }  // end namespace
 }  // end namespace
-#endif
diff --git a/MaterialLib/FractureModels/CreateLinearElasticIsotropic.h b/MaterialLib/FractureModels/CreateLinearElasticIsotropic.h
index c548d9a1562..18acc517058 100644
--- a/MaterialLib/FractureModels/CreateLinearElasticIsotropic.h
+++ b/MaterialLib/FractureModels/CreateLinearElasticIsotropic.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALLIB_FRACTURE_CREATELINEARELASTICISOTROPIC_H_
-#define MATERIALLIB_FRACTURE_CREATELINEARELASTICISOTROPIC_H_
+#pragma once
 
 #include "FractureModelBase.h"
 
@@ -25,5 +24,3 @@ createLinearElasticIsotropic(
 
 }  // namespace Fracture
 }  // namespace MaterialLib
-
-#endif
diff --git a/MaterialLib/FractureModels/CreateMohrCoulomb.h b/MaterialLib/FractureModels/CreateMohrCoulomb.h
index 70fc71f7b05..4571647bc74 100644
--- a/MaterialLib/FractureModels/CreateMohrCoulomb.h
+++ b/MaterialLib/FractureModels/CreateMohrCoulomb.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALLIB_FRACTURE_CREATEMOHRCOULOMB_H_
-#define MATERIALLIB_FRACTURE_CREATEMOHRCOULOMB_H_
+#pragma once
 
 #include "FractureModelBase.h"
 
@@ -25,5 +24,3 @@ createMohrCoulomb(
 
 }  // namespace Fracture
 }  // namespace MaterialLib
-
-#endif
diff --git a/MaterialLib/FractureModels/FractureIdentity2.h b/MaterialLib/FractureModels/FractureIdentity2.h
index 3c43197649d..538a51ab16d 100644
--- a/MaterialLib/FractureModels/FractureIdentity2.h
+++ b/MaterialLib/FractureModels/FractureIdentity2.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALLIB_FRACTURE_IDENTITY2_H_
-#define MATERIALLIB_FRACTURE_IDENTITY2_H_
+#pragma once
 
 #include <Eigen/Eigen>
 
@@ -32,5 +31,3 @@ extern template struct FractureIdentity2<3>;
 
 }  // namespace Fracture
 }  // namespace MaterialLib
-
-#endif // MATERIALLIB_FRACTURE_IDENTITY2_H_
diff --git a/MaterialLib/FractureModels/FractureModelBase.h b/MaterialLib/FractureModels/FractureModelBase.h
index 62a8314e0ac..f82f126f850 100644
--- a/MaterialLib/FractureModels/FractureModelBase.h
+++ b/MaterialLib/FractureModels/FractureModelBase.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALLIB_FRACTURE_FRACTUREMODELBASE_H_
-#define MATERIALLIB_FRACTURE_FRACTUREMODELBASE_H_
+#pragma once
 
 #include <Eigen/Eigen>
 
@@ -88,5 +87,3 @@ public:
 
 }  // namespace Fracture
 }  // namespace MaterialLib
-
-#endif
diff --git a/MaterialLib/FractureModels/LinearElasticIsotropic.h b/MaterialLib/FractureModels/LinearElasticIsotropic.h
index 089447bc41d..7c44ede3f58 100644
--- a/MaterialLib/FractureModels/LinearElasticIsotropic.h
+++ b/MaterialLib/FractureModels/LinearElasticIsotropic.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALLIB_FRACTURE_LINEARELASTICISOTROPIC_H_
-#define MATERIALLIB_FRACTURE_LINEARELASTICISOTROPIC_H_
+#pragma once
 
 #include <Eigen/Eigen>
 
@@ -100,5 +99,3 @@ extern template class LinearElasticIsotropic<2>;
 extern template class LinearElasticIsotropic<3>;
 }  // namespace Fractrue
 }  // namespace MaterialLib
-
-#endif
diff --git a/MaterialLib/FractureModels/MohrCoulomb.h b/MaterialLib/FractureModels/MohrCoulomb.h
index b372bde219e..a16744bd5ac 100644
--- a/MaterialLib/FractureModels/MohrCoulomb.h
+++ b/MaterialLib/FractureModels/MohrCoulomb.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALLIB_FRACTURE_MOHRCOULOMB_H_
-#define MATERIALLIB_FRACTURE_MOHRCOULOMB_H_
+#pragma once
 
 #include <Eigen/Eigen>
 
@@ -111,5 +110,3 @@ extern template class MohrCoulomb<2>;
 extern template class MohrCoulomb<3>;
 }  // namespace Fractrue
 }  // namespace MaterialLib
-
-#endif
diff --git a/MaterialLib/PhysicalConstant.h b/MaterialLib/PhysicalConstant.h
index 60102476de9..cce50a0e92d 100644
--- a/MaterialLib/PhysicalConstant.h
+++ b/MaterialLib/PhysicalConstant.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef MATERIALSLIB_PHYSICALCONSTANT_H
-#define MATERIALSLIB_PHYSICALCONSTANT_H
+#pragma once
 
 namespace MaterialLib
 {
@@ -89,4 +88,3 @@ const double WaterVapour = IdealGasConstant / MolarMass::Water;  // = 461.504;
 }  // namespace SpecificGasConstant
 }  // namespace PhysicalConstant
 }  // namespace MaterialLib
-#endif  // MATERIALSLIB_PHYSICALCONSTANT_H
diff --git a/MaterialLib/PorousMedium/Permeability/createPermeabilityModel.h b/MaterialLib/PorousMedium/Permeability/createPermeabilityModel.h
index fb408c7ef38..d7503a845d2 100644
--- a/MaterialLib/PorousMedium/Permeability/createPermeabilityModel.h
+++ b/MaterialLib/PorousMedium/Permeability/createPermeabilityModel.h
@@ -10,8 +10,7 @@
  * Created on August 17, 2016, 2:36 PM
  */
 
-#ifndef OGS_CREATEPERMEABILITYMODEL_H
-#define OGS_CREATEPERMEABILITYMODEL_H
+#pragma once
 
 #include <Eigen/Dense>
 
@@ -31,5 +30,3 @@ Eigen::MatrixXd createPermeabilityModel(BaseLib::ConfigTree const& config);
 
 }  // end of namespace
 }  // end of namespace
-
-#endif /* CREATEPERMEABILITYMODEL_H */
diff --git a/MaterialLib/PorousMedium/Porosity/ConstantPorosity.h b/MaterialLib/PorousMedium/Porosity/ConstantPorosity.h
index 9410199a5bd..19a6b02cddc 100644
--- a/MaterialLib/PorousMedium/Porosity/ConstantPorosity.h
+++ b/MaterialLib/PorousMedium/Porosity/ConstantPorosity.h
@@ -10,8 +10,7 @@
  * Created on August 16, 2016, 1:03 PM
  */
 
-#ifndef OGS_CONSTANTPOROSITY_H
-#define OGS_CONSTANTPOROSITY_H
+#pragma once
 
 #include "Porosity.h"
 
@@ -45,5 +44,3 @@ private:
 
 }  // end of namespace
 }  // end of namespace
-
-#endif /* CONSTANTPOROSITY_H */
diff --git a/MaterialLib/PorousMedium/Porosity/Porosity.h b/MaterialLib/PorousMedium/Porosity/Porosity.h
index 9c210194769..a2cf8e3bdc4 100644
--- a/MaterialLib/PorousMedium/Porosity/Porosity.h
+++ b/MaterialLib/PorousMedium/Porosity/Porosity.h
@@ -10,8 +10,7 @@
  * Created on August 16, 2016, 12:53 PM
  */
 
-#ifndef OGS_POROSITY_H
-#define OGS_POROSITY_H
+#pragma once
 
 #include <string>
 
@@ -39,5 +38,3 @@ public:
 
 }  // end of namespace
 }  // end of namespace
-
-#endif /* POROSITY_H */
diff --git a/MaterialLib/PorousMedium/Porosity/createPorosityModel.h b/MaterialLib/PorousMedium/Porosity/createPorosityModel.h
index fd4a3725c49..8aad3e08036 100644
--- a/MaterialLib/PorousMedium/Porosity/createPorosityModel.h
+++ b/MaterialLib/PorousMedium/Porosity/createPorosityModel.h
@@ -10,8 +10,7 @@
  * Created on August 16, 2016, 1:16 PM
  */
 
-#ifndef OGS_CREATEPOROSITYMODEL_H
-#define OGS_CREATEPOROSITYMODEL_H
+#pragma once
 
 #include <memory>
 
@@ -34,5 +33,3 @@ std::unique_ptr<Porosity> createPorosityModel(
 
 }  // end namespace
 }  // end namespace
-
-#endif /* CREATEPOROSITYMODEL_H */
diff --git a/MaterialLib/PorousMedium/PorousPropertyHeaders.h b/MaterialLib/PorousMedium/PorousPropertyHeaders.h
index f816a5c6402..6154b879514 100644
--- a/MaterialLib/PorousMedium/PorousPropertyHeaders.h
+++ b/MaterialLib/PorousMedium/PorousPropertyHeaders.h
@@ -10,11 +10,8 @@
  * Created on August 18, 2016, 11:12 AM
  */
 
-#ifndef OGS_POROUSPROPERTYHEADERS_H
-#define OGS_POROUSPROPERTYHEADERS_H
+#pragma once
 
 #include "Permeability/createPermeabilityModel.h"
 #include "Porosity/createPorosityModel.h"
 #include "Storage/createStorageModel.h"
-
-#endif /* POROUSPROPERTYHEADERS_H */
diff --git a/MaterialLib/PorousMedium/Storage/ConstantStorage.h b/MaterialLib/PorousMedium/Storage/ConstantStorage.h
index 5a5c649e40b..acb5939f326 100644
--- a/MaterialLib/PorousMedium/Storage/ConstantStorage.h
+++ b/MaterialLib/PorousMedium/Storage/ConstantStorage.h
@@ -10,8 +10,7 @@
  * Created on August 16, 2016, 1:03 PM
  */
 
-#ifndef OGS_CONSTANTSTORAGE_H
-#define OGS_CONSTANTSTORAGE_H
+#pragma once
 
 #include "Storage.h"
 
@@ -43,5 +42,3 @@ private:
 
 }  // end of namespace
 }  // end of namespace
-
-#endif /* CONSTANTSTORAGE_H */
diff --git a/MaterialLib/PorousMedium/Storage/Storage.h b/MaterialLib/PorousMedium/Storage/Storage.h
index c06957adf9a..dd8d757d49b 100644
--- a/MaterialLib/PorousMedium/Storage/Storage.h
+++ b/MaterialLib/PorousMedium/Storage/Storage.h
@@ -10,8 +10,7 @@
  * Created on August 16, 2016, 12:53 PM
  */
 
-#ifndef OGS_STORAGE_H
-#define OGS_STORAGE_H
+#pragma once
 
 #include <string>
 
@@ -35,5 +34,3 @@ public:
 
 }  // end of namespace
 }  // end of namespace
-
-#endif /* STORAGE_H */
diff --git a/MaterialLib/PorousMedium/Storage/createStorageModel.h b/MaterialLib/PorousMedium/Storage/createStorageModel.h
index 041638ddfa2..ab36494e421 100644
--- a/MaterialLib/PorousMedium/Storage/createStorageModel.h
+++ b/MaterialLib/PorousMedium/Storage/createStorageModel.h
@@ -10,8 +10,7 @@
  * Created on August 16, 2016, 1:16 PM
  */
 
-#ifndef OGS_CREATESTORAGEMODEL_H
-#define OGS_CREATESTORAGEMODEL_H
+#pragma once
 
 #include <memory>
 
@@ -32,5 +31,3 @@ std::unique_ptr<Storage> createStorageModel(BaseLib::ConfigTree const& config);
 
 }  // end namespace
 }  // end namespace
-
-#endif /* CREATESTORAGEMODEL_H */
diff --git a/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/BrookCoreyCapillaryPressureSaturation.h b/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/BrookCoreyCapillaryPressureSaturation.h
index cd2e8f7482e..519f2ee1a96 100644
--- a/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/BrookCoreyCapillaryPressureSaturation.h
+++ b/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/BrookCoreyCapillaryPressureSaturation.h
@@ -10,8 +10,7 @@
  *  Created on November 1, 2016, 9:45 AM
  */
 
-#ifndef OGS_BROOK_COREY_CAPILLARY_PRESSURE_SATURATION_H
-#define OGS_BROOK_COREY_CAPILLARY_PRESSURE_SATURATION_H
+#pragma once
 
 #include <limits>  // std::numeric_limits
 
@@ -78,4 +77,3 @@ private:
 
 }  // end namespace
 }  // end namespace
-#endif /* OGS_BROOK_COREY_CAPILLARY_PRESSURE_SATURATION_H */
diff --git a/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/CapillaryPressureSaturation.h b/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/CapillaryPressureSaturation.h
index d5f72af864e..b3dbf9dc6ff 100644
--- a/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/CapillaryPressureSaturation.h
+++ b/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/CapillaryPressureSaturation.h
@@ -9,8 +9,7 @@
  *
  */
 
-#ifndef OGS_CAPILLARY_PRESSURE_SATURATION_H
-#define OGS_CAPILLARY_PRESSURE_SATURATION_H
+#pragma once
 
 #include <string>
 
@@ -62,5 +61,3 @@ protected:
 
 }  // end namespace
 }  // end namespace
-
-#endif /* OGS_CAPILLARY_PRESSURE_SATURATION_H */
diff --git a/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/CapillaryPressureSaturationCurve.h b/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/CapillaryPressureSaturationCurve.h
index 59c9480477e..63dc649c195 100644
--- a/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/CapillaryPressureSaturationCurve.h
+++ b/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/CapillaryPressureSaturationCurve.h
@@ -10,8 +10,7 @@
  * Created on November 3, 2016, 9:50 AM
  */
 
-#ifndef OGS_CAPILLARY_PRESSURE_SATURATION_CURVE_H
-#define OGS_CAPILLARY_PRESSURE_SATURATION_CURVE_H
+#pragma once
 
 #include <memory>
 
@@ -78,5 +77,3 @@ private:
 
 }  // end namespace
 }  // end namespace
-
-#endif /* OGS_CAPILLARY_PRESSURE_SATURATION_CURVE_H */
diff --git a/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/CreateCapillaryPressureModel.h b/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/CreateCapillaryPressureModel.h
index bc6b07ba60b..ff2929112f2 100644
--- a/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/CreateCapillaryPressureModel.h
+++ b/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/CreateCapillaryPressureModel.h
@@ -10,8 +10,7 @@
  * Created on November 1, 2016, 10:06 AM
  */
 
-#ifndef OGS_CREATE_CAPILLARY_PRESSURE_MODEL_H
-#define OGS_CREATE_CAPILLARY_PRESSURE_MODEL_H
+#pragma once
 
 #include <memory>
 
@@ -31,5 +30,3 @@ std::unique_ptr<CapillaryPressureSaturation> createCapillaryPressureModel(
     BaseLib::ConfigTree const& config);
 }
 }  // end namespace
-
-#endif /* OGS_CREATE_CAPILLARY_PRESSURE_MODEL_H */
diff --git a/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/VanGenuchtenCapillaryPressureSaturation.h b/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/VanGenuchtenCapillaryPressureSaturation.h
index 78d02e562ae..3c60b0d1fa4 100644
--- a/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/VanGenuchtenCapillaryPressureSaturation.h
+++ b/MaterialLib/PorousMedium/UnsaturatedProperty/CapillaryPressure/VanGenuchtenCapillaryPressureSaturation.h
@@ -10,8 +10,7 @@
  *  Created on October 28, 2016, 6:05 PM
  */
 
-#ifndef OGS_VAN_GENUCHTEN_CAPILLARY_PRESSURE_SATURATION_H
-#define OGS_VAN_GENUCHTEN_CAPILLARY_PRESSURE_SATURATION_H
+#pragma once
 
 #include <limits>
 
@@ -83,4 +82,3 @@ private:
 
 }  // end namespace
 }  // end namespace
-#endif /* OGS_VAN_GENUCHTEN_CAPILLARY_PRESSURE_SATURATION_H */
diff --git a/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/CreateRelativePermeabilityModel.h b/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/CreateRelativePermeabilityModel.h
index a93bda565ee..78d15b53598 100644
--- a/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/CreateRelativePermeabilityModel.h
+++ b/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/CreateRelativePermeabilityModel.h
@@ -10,8 +10,7 @@
  * Created on November 2, 2016, 11:43 AM
  */
 
-#ifndef OGS_CREATE_RELATIVE_PERMEABILITY_MODEL_H
-#define OGS_CREATE_RELATIVE_PERMEABILITY_MODEL_H
+#pragma once
 
 #include <memory>
 
@@ -31,5 +30,3 @@ std::unique_ptr<RelativePermeability> createRelativePermeabilityModel(
     BaseLib::ConfigTree const& config);
 }
 }  // end namespace
-
-#endif /* OGS_CREATE_RELATIVE_PERMEABILITY_MODEL_H */
diff --git a/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/NonWettingPhaseBrookCoreyOilGas.h b/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/NonWettingPhaseBrookCoreyOilGas.h
index cc2a2193dfb..2361d92a0a5 100644
--- a/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/NonWettingPhaseBrookCoreyOilGas.h
+++ b/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/NonWettingPhaseBrookCoreyOilGas.h
@@ -10,8 +10,7 @@
  * Created on November 2, 2016, 10:47 AM
  */
 
-#ifndef OGS_NON_WETTING_PHASE_BROOK_COREY_OIL_GAS_H
-#define OGS_NON_WETTING_PHASE_BROOK_COREY_OIL_GAS_H
+#pragma once
 
 #include "RelativePermeability.h"
 
@@ -73,5 +72,3 @@ private:
 
 }  // end namespace
 }  // end namespace
-
-#endif /* OGS_NON_WETTING_PHASE_BROOK_COREY_OIL_GAS_H */
diff --git a/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/NonWettingPhaseVanGenuchten.h b/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/NonWettingPhaseVanGenuchten.h
index dada1be4732..88d131cf639 100644
--- a/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/NonWettingPhaseVanGenuchten.h
+++ b/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/NonWettingPhaseVanGenuchten.h
@@ -9,8 +9,7 @@
  *
  * Created on November 2, 2016, 11:24 AM
  */
-#ifndef OGS_NON_WETTING_PHASE_VAN_GENUCHTEN_H
-#define OGS_NON_WETTING_PHASE_VAN_GENUCHTEN_H
+#pragma once
 
 #include "RelativePermeability.h"
 
@@ -75,4 +74,3 @@ private:
 
 }  // end namespace
 }  // end namespace
-#endif /* OGS_NON_WETTING_PHASE_VAN_GENUCHTEN_H */
diff --git a/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/RelativePermeability.h b/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/RelativePermeability.h
index 281b2046426..31f59b044ca 100644
--- a/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/RelativePermeability.h
+++ b/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/RelativePermeability.h
@@ -9,8 +9,7 @@
  *
  */
 
-#ifndef OGS_RELATIVE_PERMEABILITY_H
-#define OGS_RELATIVE_PERMEABILITY_H
+#pragma once
 
 #include <string>
 #include <limits>
@@ -54,5 +53,3 @@ protected:
 
 }  // end namespace
 }  // end namespace
-
-#endif /* OGS_RELATIVE_PERMEABILITY_H */
diff --git a/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/RelativePermeabilityCurve.h b/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/RelativePermeabilityCurve.h
index 09618d28848..fa2987ecb6b 100644
--- a/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/RelativePermeabilityCurve.h
+++ b/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/RelativePermeabilityCurve.h
@@ -10,8 +10,7 @@
  * Created on November 2, 2016, 1:41 PM
  */
 
-#ifndef OGS_RELATIVE_PERMEABILITY_CURVE_H
-#define OGS_RELATIVE_PERMEABILITY_CURVE_H
+#pragma once
 
 #include <memory>
 #include "RelativePermeability.h"
@@ -66,4 +65,3 @@ private:
 };
 }  // end namespace
 }  // end namespace
-#endif /* OGS_RELATIVE_PERMEABILITY_CURVE_H */
diff --git a/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/WettingPhaseBrookCoreyOilGas.h b/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/WettingPhaseBrookCoreyOilGas.h
index e5023b0474a..30a9e87ce4a 100644
--- a/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/WettingPhaseBrookCoreyOilGas.h
+++ b/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/WettingPhaseBrookCoreyOilGas.h
@@ -10,8 +10,7 @@
  * Created on November 1, 2016, 3:37 PM
  */
 
-#ifndef OGS_WETTING_PHASE_BROOK_COREY_OIL_GAS_H
-#define OGS_WETTING_PHASE_BROOK_COREY_OIL_GAS_H
+#pragma once
 
 #include "RelativePermeability.h"
 
@@ -67,4 +66,3 @@ private:
 
 }  // end namespace
 }  // end namespace
-#endif /* OGS_WETTING_PHASE_BROOK_COREY_OIL_GAS_H */
diff --git a/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/WettingPhaseVanGenuchten.h b/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/WettingPhaseVanGenuchten.h
index f501b6bbc21..7e0982983cb 100644
--- a/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/WettingPhaseVanGenuchten.h
+++ b/MaterialLib/PorousMedium/UnsaturatedProperty/RelativePermeability/WettingPhaseVanGenuchten.h
@@ -10,8 +10,7 @@
  * Created on November 2, 2016, 11:24 AM
  */
 
-#ifndef OGS_WETTING_PHASE_VAN_GENUCHTEN_H
-#define OGS_WETTING_PHASE_VAN_GENUCHTEN_H
+#pragma once
 
 #include "RelativePermeability.h"
 
@@ -70,4 +69,3 @@ private:
 
 }  // end namespace
 }  // end namespace
-#endif /* OGS_WETTING_PHASE_VAN_GENUCHTEN_H */
diff --git a/MaterialLib/SolidModels/CreateEhlers.h b/MaterialLib/SolidModels/CreateEhlers.h
index 2bc1c17cb99..1f80ef3eac9 100644
--- a/MaterialLib/SolidModels/CreateEhlers.h
+++ b/MaterialLib/SolidModels/CreateEhlers.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALLIB_SOLIDMODELS_CREATEEHLERS_H_
-#define MATERIALLIB_SOLIDMODELS_CREATEEHLERS_H_
+#pragma once
 
 #include <logog/include/logog.hpp>
 
@@ -151,5 +150,3 @@ std::unique_ptr<MechanicsBase<DisplacementDim>> createEhlers(
 
 }  // namespace Solids
 }  // namespace MaterialLib
-
-#endif  // MATERIALLIB_SOLIDMODELS_CREATEEHLERS_H_
diff --git a/MaterialLib/SolidModels/CreateLinearElasticIsotropic.h b/MaterialLib/SolidModels/CreateLinearElasticIsotropic.h
index 8518288040a..29110bfa9fa 100644
--- a/MaterialLib/SolidModels/CreateLinearElasticIsotropic.h
+++ b/MaterialLib/SolidModels/CreateLinearElasticIsotropic.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALLIB_SOLIDMODELS_CREATELINEARELASTICISOTROPIC_H_
-#define MATERIALLIB_SOLIDMODELS_CREATELINEARELASTICISOTROPIC_H_
+#pragma once
 
 #include "ProcessLib/Utils/ProcessUtils.h"  // required for findParameter
 #include "LinearElasticIsotropic.h"
@@ -51,5 +50,3 @@ createLinearElasticIsotropic(
 
 }  // namespace Solids
 }  // namespace MaterialLib
-
-#endif  // MATERIALLIB_SOLIDMODELS_CREATELINEARELASTICISOTROPIC_H_
diff --git a/MaterialLib/SolidModels/CreateLubby2.h b/MaterialLib/SolidModels/CreateLubby2.h
index b3d76de47d1..0edd11f0181 100644
--- a/MaterialLib/SolidModels/CreateLubby2.h
+++ b/MaterialLib/SolidModels/CreateLubby2.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALLIB_SOLIDMODELS_CREATELUBBY2_H_
-#define MATERIALLIB_SOLIDMODELS_CREATELUBBY2_H_
+#pragma once
 
 #include <logog/include/logog.hpp>
 
@@ -106,5 +105,3 @@ std::unique_ptr<MechanicsBase<DisplacementDim>> createLubby2(
 
 }  // namespace Solids
 }  // namespace MaterialLib
-
-#endif  // MATERIALLIB_SOLIDMODELS_CREATELUBBY2_H_
diff --git a/MaterialLib/SolidModels/Ehlers-impl.h b/MaterialLib/SolidModels/Ehlers-impl.h
index 8926fce655c..1527e7b6b17 100644
--- a/MaterialLib/SolidModels/Ehlers-impl.h
+++ b/MaterialLib/SolidModels/Ehlers-impl.h
@@ -30,8 +30,7 @@
  * lambda_flow_D    - deviatoric increment of plastic strain
  *
  */
-#ifndef MATERIALLIB_SOLIDMODELS_EHLERS_IMPL_H_
-#define MATERIALLIB_SOLIDMODELS_EHLERS_IMPL_H_
+#pragma once
 
 #include <boost/math/special_functions/pow.hpp>
 #include <logog/include/logog.hpp>
@@ -657,5 +656,3 @@ bool SolidEhlers<DisplacementDim>::computeConstitutiveRelation(
 
 }  // namespace Solids
 }  // namespace MaterialLib
-
-#endif  // MATERIALLIB_SOLIDMODELS_EHLERS_IMPL_H_
diff --git a/MaterialLib/SolidModels/Ehlers.h b/MaterialLib/SolidModels/Ehlers.h
index af640986378..d50a5ff6a15 100644
--- a/MaterialLib/SolidModels/Ehlers.h
+++ b/MaterialLib/SolidModels/Ehlers.h
@@ -17,8 +17,7 @@
  * for more details for the tests.
  */
 
-#ifndef MATERIALLIB_SOLIDMODELS_EHLERS_H_
-#define MATERIALLIB_SOLIDMODELS_EHLERS_H_
+#pragma once
 
 #include <cfloat>
 #include <memory>
@@ -211,5 +210,3 @@ private:
 }  // namespace Solids
 }  // namespace MaterialLib
 #include "Ehlers-impl.h"
-
-#endif  // MATERIALLIB_SOLIDMODELS_EHLERS_H_
diff --git a/MaterialLib/SolidModels/KelvinVector.h b/MaterialLib/SolidModels/KelvinVector.h
index d3f7865351a..d6253f61ce4 100644
--- a/MaterialLib/SolidModels/KelvinVector.h
+++ b/MaterialLib/SolidModels/KelvinVector.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  *
  */
-#ifndef MATERIALLIB_SOLIDMODELS_KELVINVECTOR_H
-#define MATERIALLIB_SOLIDMODELS_KELVINVECTOR_H
+#pragma once
 
 #include <Eigen/Dense>
 
@@ -80,5 +79,3 @@ inverse(Eigen::Matrix<double,
 }  // namespace MaterialLib
 
 #include "KelvinVector-impl.h"
-
-#endif  // MATERIALLIB_SOLIDMODELS_KELVINVECTOR_H
diff --git a/MaterialLib/SolidModels/LinearElasticIsotropic.h b/MaterialLib/SolidModels/LinearElasticIsotropic.h
index d66e9ff6d1f..3342eb0b438 100644
--- a/MaterialLib/SolidModels/LinearElasticIsotropic.h
+++ b/MaterialLib/SolidModels/LinearElasticIsotropic.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALLIB_SOLIDMODELS_LINEARELASTICISOTROPIC_H_
-#define MATERIALLIB_SOLIDMODELS_LINEARELASTICISOTROPIC_H_
+#pragma once
 
 #include "MechanicsBase.h"
 
@@ -109,5 +108,3 @@ extern template class LinearElasticIsotropic<3>;
 
 }  // namespace Solids
 }  // namespace MaterialLib
-
-#endif  // MATERIALLIB_SOLIDMODELS_LINEARELASTICISOTROPIC_H_
diff --git a/MaterialLib/SolidModels/Lubby2-impl.h b/MaterialLib/SolidModels/Lubby2-impl.h
index 42a804db341..a52ace4bdcd 100644
--- a/MaterialLib/SolidModels/Lubby2-impl.h
+++ b/MaterialLib/SolidModels/Lubby2-impl.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALLIB_SOLIDMODELS_LUBBY2_IMPL_H_
-#define MATERIALLIB_SOLIDMODELS_LUBBY2_IMPL_H_
+#pragma once
 
 #include "NumLib/NewtonRaphson.h"
 
@@ -267,5 +266,3 @@ void Lubby2<DisplacementDim>::calculateJacobianBurgers(
 
 }  // namespace Solids
 }  // namespace MaterialLib
-
-#endif  // MATERIALLIB_SOLIDMODELS_LUBBY2_IMPL_H_
diff --git a/MaterialLib/SolidModels/Lubby2.h b/MaterialLib/SolidModels/Lubby2.h
index 9ee8ec330fb..2580349fbe0 100644
--- a/MaterialLib/SolidModels/Lubby2.h
+++ b/MaterialLib/SolidModels/Lubby2.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALLIB_SOLIDMODELS_LUBBY2_H_
-#define MATERIALLIB_SOLIDMODELS_LUBBY2_H_
+#pragma once
 
 #include <logog/include/logog.hpp>
 
@@ -201,5 +200,3 @@ extern template class Lubby2<3>;
 }  // namespace MaterialLib
 
 #include "Lubby2-impl.h"
-
-#endif  // MATERIALLIB_SOLIDMODELS_LUBBY2_H_
diff --git a/MaterialLib/SolidModels/MechanicsBase.h b/MaterialLib/SolidModels/MechanicsBase.h
index f41050cf9a6..23292e0f0e8 100644
--- a/MaterialLib/SolidModels/MechanicsBase.h
+++ b/MaterialLib/SolidModels/MechanicsBase.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATERIALLIB_SOLIDMODELS_MECHANICSBASE_H_
-#define MATERIALLIB_SOLIDMODELS_MECHANICSBASE_H_
+#pragma once
 
 #include <memory>
 
@@ -116,5 +115,3 @@ struct MechanicsBase
 
 }  // namespace Solids
 }  // namespace MaterialLib
-
-#endif  // MATERIALLIB_SOLIDMODELS_MECHANICSBASE_H_
diff --git a/MaterialLib/TwoPhaseModels/CreateTwoPhaseFlowMaterialProperties.h b/MaterialLib/TwoPhaseModels/CreateTwoPhaseFlowMaterialProperties.h
index b1af6fe6a4f..bbf4f4309a9 100644
--- a/MaterialLib/TwoPhaseModels/CreateTwoPhaseFlowMaterialProperties.h
+++ b/MaterialLib/TwoPhaseModels/CreateTwoPhaseFlowMaterialProperties.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef OGS_CREATETWOPHASEFLOWMATERIALPROPERTIES_H
-#define OGS_CREATETWOPHASEFLOWMATERIALPROPERTIES_H
+#pragma once
 
 #include <memory>
 #include "MaterialLib/Fluid/FluidPropertyHeaders.h"
@@ -33,5 +32,3 @@ CreateTwoPhaseFlowMaterialProperties(
 
 }  // end namespace
 }  // end namespace
-
-#endif /* CREATETWOPHASEFLOWMATERIALPROPERTIES_H */
diff --git a/MaterialLib/TwoPhaseModels/TwoPhaseFlowWithPPMaterialProperties.h b/MaterialLib/TwoPhaseModels/TwoPhaseFlowWithPPMaterialProperties.h
index ba8cba0c15c..977cc26e61c 100644
--- a/MaterialLib/TwoPhaseModels/TwoPhaseFlowWithPPMaterialProperties.h
+++ b/MaterialLib/TwoPhaseModels/TwoPhaseFlowWithPPMaterialProperties.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef OGS_TWOPHASEFLOWWITHPPMATERIALPROPERTIES_H
-#define OGS_TWOPHASEFLOWWITHPPMATERIALPROPERTIES_H
+#pragma once
 
 #include <iostream>
 #include <memory>
@@ -102,4 +101,3 @@ protected:
 
 }  // end of namespace
 }  // end of namespace
-#endif /* TWOPHASEFLOWWITHPPMATERIALPROPERTIES_H */
diff --git a/MathLib/ConstantFunction.h b/MathLib/ConstantFunction.h
index f36bd17e980..082f4f51c1f 100644
--- a/MathLib/ConstantFunction.h
+++ b/MathLib/ConstantFunction.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef MATHLIB_CONSTANTFUNCTION_H_
-#define MATHLIB_CONSTANTFUNCTION_H_
+#pragma once
 
 #include <array>
 #include <numeric>
@@ -42,5 +41,3 @@ private:
 };
 
 }
-
-#endif  // MATHLIB_CONSTANTFUNCTION_H_
diff --git a/MathLib/Curve/CreatePiecewiseLinearCurve.h b/MathLib/Curve/CreatePiecewiseLinearCurve.h
index f4c5d0cec95..088139a7e3f 100644
--- a/MathLib/Curve/CreatePiecewiseLinearCurve.h
+++ b/MathLib/Curve/CreatePiecewiseLinearCurve.h
@@ -10,8 +10,7 @@
  * Created on November 11, 2016, 10:49 AM
  */
 
-#ifndef OGS_CREATE_PIECEWISE_LINEAR_CURVE_H
-#define OGS_CREATE_PIECEWISE_LINEAR_CURVE_H
+#pragma once
 
 #include <memory>
 
@@ -30,5 +29,3 @@ std::unique_ptr<CurveType> createPiecewiseLinearCurve(
 };
 
 #include "CreatePiecewiseLinearCurve-impl.h"
-
-#endif /* OGS_CREATE_PIECEWISE_LINEAR_CURVE_H */
diff --git a/MathLib/Curve/PiecewiseLinearMonotonicCurve.h b/MathLib/Curve/PiecewiseLinearMonotonicCurve.h
index 10a0f8869db..b0e5ac7d261 100644
--- a/MathLib/Curve/PiecewiseLinearMonotonicCurve.h
+++ b/MathLib/Curve/PiecewiseLinearMonotonicCurve.h
@@ -10,8 +10,7 @@
  * Created on November 11, 2016, 10:49 AM
  */
 
-#ifndef OGS_PIECE_WISE_LINEAR_MONOTONIC_CURVE_H
-#define OGS_PIECE_WISE_LINEAR_MONOTONIC_CURVE_H
+#pragma once
 
 #include "MathLib/InterpolationAlgorithms/PiecewiseLinearInterpolation.h"
 
@@ -46,4 +45,3 @@ private:
     bool isStrongMonotonic() const;
 };
 }  // namespace
-#endif /* OGS_PIECE_WISE_LINEAR_MONOTONIC_CURVE_H */
diff --git a/MathLib/GeometricBasics.h b/MathLib/GeometricBasics.h
index c4458d26b7e..52d66619b6d 100644
--- a/MathLib/GeometricBasics.h
+++ b/MathLib/GeometricBasics.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef GEOMETRIC_BASICS_H_
-#define GEOMETRIC_BASICS_H_
+#pragma once
 
 #include <cstddef>
 #include <limits>
@@ -179,5 +178,3 @@ bool isCoplanar(const MathLib::Point3d& a, const MathLib::Point3d& b,
                 const MathLib::Point3d& c, const MathLib::Point3d& d);
 
 }  // end namespace MathLib
-
-#endif
diff --git a/MathLib/Integration/GaussLegendre.h b/MathLib/Integration/GaussLegendre.h
index 24b5d8f18ec..bb81692839f 100644
--- a/MathLib/Integration/GaussLegendre.h
+++ b/MathLib/Integration/GaussLegendre.h
@@ -10,9 +10,7 @@
  *
  */
 
-
-#ifndef GAUSSLEGENDRE_H_
-#define GAUSSLEGENDRE_H_
+#pragma once
 
 #include "WeightedSum.h"
 
@@ -50,6 +48,3 @@ double const GaussLegendre<4>::W[4];
 #endif
 
 }  // namespace MathLib
-
-#endif // GAUSSLEGENDRE_H_
-
diff --git a/MathLib/Integration/GaussLegendrePyramid.h b/MathLib/Integration/GaussLegendrePyramid.h
index b62b5b54f22..980075bf1bd 100644
--- a/MathLib/Integration/GaussLegendrePyramid.h
+++ b/MathLib/Integration/GaussLegendrePyramid.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef GAUSSLEGENDREPYRAMID_H_
-#define GAUSSLEGENDREPYRAMID_H_
+#pragma once
 
 #include <array>
 
@@ -51,5 +50,3 @@ template <>
 double const GaussLegendrePyramid<1>::W[1];
 #endif
 }
-
-#endif //GAUSSLEGENDREPYRAMID_H_
diff --git a/MathLib/Integration/GaussLegendreTet.h b/MathLib/Integration/GaussLegendreTet.h
index da09966a0f7..43bf8e69603 100644
--- a/MathLib/Integration/GaussLegendreTet.h
+++ b/MathLib/Integration/GaussLegendreTet.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef GAUSSLEGENDRETET_H_
-#define GAUSSLEGENDRETET_H_
+#pragma once
 
 #include <array>
 
@@ -51,5 +50,3 @@ template <>
 double const GaussLegendreTet<1>::W[1];
 #endif
 }
-
-#endif //GAUSSLEGENDRETET_H_
diff --git a/MathLib/Integration/GaussLegendreTri.h b/MathLib/Integration/GaussLegendreTri.h
index 37d13d52402..55fc4a805cd 100644
--- a/MathLib/Integration/GaussLegendreTri.h
+++ b/MathLib/Integration/GaussLegendreTri.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef GAUSSLEGENDRETRI_H_
-#define GAUSSLEGENDRETRI_H_
+#pragma once
 
 #include <array>
 
@@ -56,5 +55,3 @@ template <>
 double const GaussLegendreTri<1>::W[1];
 #endif
 }
-
-#endif //GAUSSLEGENDRETRI_H_
diff --git a/MathLib/Integration/WeightedSum.h b/MathLib/Integration/WeightedSum.h
index c89ad4ffc9f..ff8c01bd5e6 100644
--- a/MathLib/Integration/WeightedSum.h
+++ b/MathLib/Integration/WeightedSum.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATHLIB_WEIGHTEDSUM_H_
-#define MATHLIB_WEIGHTEDSUM_H_
+#pragma once
 
 namespace MathLib
 {
@@ -63,5 +62,3 @@ struct WeightedSum
 };
 
 }   // namespace MathLib
-
-#endif  // MATHLIB_WEIGHTEDSUM_H_
diff --git a/MathLib/InterpolationAlgorithms/LinearIntervalInterpolation.h b/MathLib/InterpolationAlgorithms/LinearIntervalInterpolation.h
index 0d2f100a112..318e4f0780d 100644
--- a/MathLib/InterpolationAlgorithms/LinearIntervalInterpolation.h
+++ b/MathLib/InterpolationAlgorithms/LinearIntervalInterpolation.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef LINEARINTERVALINTERPOLATION_H_
-#define LINEARINTERVALINTERPOLATION_H_
+#pragma once
 
 #include "BaseLib/Error.h"
 
@@ -79,5 +78,3 @@ inline NUMERIC_TYPE LinearIntervalInterpolation<NUMERIC_TYPE>::operator() (NUMER
 }
 
 } // end namespace MathLib
-
-#endif /* LINEARINTERPOLATION_H_ */
diff --git a/MathLib/InterpolationAlgorithms/PiecewiseLinearInterpolation.h b/MathLib/InterpolationAlgorithms/PiecewiseLinearInterpolation.h
index 7520c4d1852..c9b292ca548 100644
--- a/MathLib/InterpolationAlgorithms/PiecewiseLinearInterpolation.h
+++ b/MathLib/InterpolationAlgorithms/PiecewiseLinearInterpolation.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef PIECEWISELINEARINTERPOLATION_H_
-#define PIECEWISELINEARINTERPOLATION_H_
+#pragma once
 
 #include <vector>
 
@@ -81,5 +80,3 @@ protected:
     std::vector<double> _values_at_supp_pnts;
 };
 }  // end namespace MathLib
-
-#endif /* PIECEWISELINEARINTERPOLATION_H_ */
diff --git a/MathLib/LinAlg/ApplyKnownSolution.h b/MathLib/LinAlg/ApplyKnownSolution.h
index 141970af9ac..c8ae2f56f0d 100644
--- a/MathLib/LinAlg/ApplyKnownSolution.h
+++ b/MathLib/LinAlg/ApplyKnownSolution.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef MATHLIB_APPLYKNOWNSOLUTION_H_
-#define MATHLIB_APPLYKNOWNSOLUTION_H_
+#pragma once
 
 #include <vector>
 
@@ -18,5 +17,3 @@
 #ifdef USE_PETSC
 #include "MathLib/LinAlg/PETSc/PETScTools.h"
 #endif // USE_PETSC
-
-#endif  // MATHLIB_APPLYKNOWNSOLUTION_H_
diff --git a/MathLib/LinAlg/Dense/DenseMatrix.h b/MathLib/LinAlg/Dense/DenseMatrix.h
index b0568e66f97..dd63ba7fdee 100644
--- a/MathLib/LinAlg/Dense/DenseMatrix.h
+++ b/MathLib/LinAlg/Dense/DenseMatrix.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MATRIX_H
-#define MATRIX_H
+#pragma once
 
 #include "MathLib/Vector3.h"
 
@@ -189,5 +188,3 @@ std::ostream& operator<< (std::ostream &os, const DenseMatrix<FP_TYPE, IDX_TYPE>
 } // end namespace MathLib
 
 #include "DenseMatrix-impl.h"
-
-#endif
diff --git a/MathLib/LinAlg/Eigen/EigenLinearSolver.h b/MathLib/LinAlg/Eigen/EigenLinearSolver.h
index d5d42edbee8..8ecdcc3ff2f 100644
--- a/MathLib/LinAlg/Eigen/EigenLinearSolver.h
+++ b/MathLib/LinAlg/Eigen/EigenLinearSolver.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef EIGENLINEARSOLVER_H_
-#define EIGENLINEARSOLVER_H_
+#pragma once
 
 #include <vector>
 
@@ -62,6 +61,3 @@ protected:
 };
 
 } // MathLib
-
-#endif //EIGENLINEARSOLVER_H_
-
diff --git a/MathLib/LinAlg/Eigen/EigenMapTools.h b/MathLib/LinAlg/Eigen/EigenMapTools.h
index 89a915c849a..cb1a7a8ba54 100644
--- a/MathLib/LinAlg/Eigen/EigenMapTools.h
+++ b/MathLib/LinAlg/Eigen/EigenMapTools.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATHLIB_EIGENMAPTOOLS_H
-#define MATHLIB_EIGENMAPTOOLS_H
+#pragma once
 
 #include <cassert>
 #include <vector>
@@ -211,5 +210,3 @@ inline Eigen::Map<Eigen::VectorXd> toVector(
 }
 
 }  // MathLib
-
-#endif  // MATHLIB_EIGENMAPTOOLS_H
diff --git a/MathLib/LinAlg/Eigen/EigenMatrix.h b/MathLib/LinAlg/Eigen/EigenMatrix.h
index 07f9cd565c6..7e0dd62a669 100644
--- a/MathLib/LinAlg/Eigen/EigenMatrix.h
+++ b/MathLib/LinAlg/Eigen/EigenMatrix.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef EIGENMATRIX_H_
-#define EIGENMATRIX_H_
+#pragma once
 
 #include <fstream>
 #include <string>
@@ -203,5 +202,3 @@ void operator()(EigenMatrix &matrix, SPARSITY_PATTERN const& sparsity_pattern)
 };
 
 } // end namespace MathLib
-
-#endif
diff --git a/MathLib/LinAlg/Eigen/EigenOption.h b/MathLib/LinAlg/Eigen/EigenOption.h
index 1dd7a599f87..fbf8b4b5467 100644
--- a/MathLib/LinAlg/Eigen/EigenOption.h
+++ b/MathLib/LinAlg/Eigen/EigenOption.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef EIGENOPTION_H_
-#define EIGENOPTION_H_
+#pragma once
 
 #include <string>
 
@@ -81,4 +80,3 @@ struct EigenOption final
 };
 
 }
-#endif // EIGENOPTION_H_
diff --git a/MathLib/LinAlg/Eigen/EigenTools.h b/MathLib/LinAlg/Eigen/EigenTools.h
index f88505f07cb..acf5960c785 100644
--- a/MathLib/LinAlg/Eigen/EigenTools.h
+++ b/MathLib/LinAlg/Eigen/EigenTools.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef EIGENTOOLS_H_
-#define EIGENTOOLS_H_
+#pragma once
 
 #include <vector>
 #include <logog/include/logog.hpp>
@@ -46,6 +45,3 @@ void applyKnownSolution(Eigen::MatrixXd &A, Eigen::VectorXd &b, Eigen::VectorXd
 }
 
 } // MathLib
-
-#endif //EIGENTOOLS_H_
-
diff --git a/MathLib/LinAlg/Eigen/EigenVector.h b/MathLib/LinAlg/Eigen/EigenVector.h
index 6e49f0bc3d2..d5c56e1f606 100644
--- a/MathLib/LinAlg/Eigen/EigenVector.h
+++ b/MathLib/LinAlg/Eigen/EigenVector.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef EIGENVECTOR_H_
-#define EIGENVECTOR_H_
+#pragma once
 
 #include <vector>
 #ifndef NDEBUG
@@ -122,6 +121,3 @@ private:
 };
 
 } // MathLib
-
-#endif //EIGENVECTOR_H_
-
diff --git a/MathLib/LinAlg/EigenLis/EigenLisLinearSolver.h b/MathLib/LinAlg/EigenLis/EigenLisLinearSolver.h
index 476bd544b5f..f5a05511531 100644
--- a/MathLib/LinAlg/EigenLis/EigenLisLinearSolver.h
+++ b/MathLib/LinAlg/EigenLis/EigenLisLinearSolver.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef EIGENLISLINEARSOLVER_H_
-#define EIGENLISLINEARSOLVER_H_
+#pragma once
 
 #include <vector>
 
@@ -52,6 +51,3 @@ private:
 };
 
 } // MathLib
-
-#endif //EIGENLISLINEARSOLVER_H_
-
diff --git a/MathLib/LinAlg/FinalizeMatrixAssembly.h b/MathLib/LinAlg/FinalizeMatrixAssembly.h
index 61ccaf2ce9e..a7ccbe0f618 100644
--- a/MathLib/LinAlg/FinalizeMatrixAssembly.h
+++ b/MathLib/LinAlg/FinalizeMatrixAssembly.h
@@ -11,8 +11,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef FINALIZEMATRIXASSEMBLY_H_
-#define FINALIZEMATRIXASSEMBLY_H_
+#pragma once
 
 namespace MathLib
 {
@@ -24,5 +23,3 @@ bool finalizeMatrixAssembly(MAT_T &)
 }
 
 } // MathLib
-
-#endif /* FINALIZEMATRIXASSEMBLY_H_ */
diff --git a/MathLib/LinAlg/FinalizeVectorAssembly.h b/MathLib/LinAlg/FinalizeVectorAssembly.h
index 5c85aabfe32..6c4cec43208 100644
--- a/MathLib/LinAlg/FinalizeVectorAssembly.h
+++ b/MathLib/LinAlg/FinalizeVectorAssembly.h
@@ -11,8 +11,7 @@
  *
  */
 
-#ifndef FINALIZEVECTORASSEMBLY_H_
-#define FINALIZEVECTORASSEMBLY_H_
+#pragma once
 
 namespace MathLib
 {
@@ -23,5 +22,3 @@ void finalizeVectorAssembly(VEC_T &)
 }
 
 } // MathLib
-
-#endif
diff --git a/MathLib/LinAlg/GlobalMatrixVectorTypes.h b/MathLib/LinAlg/GlobalMatrixVectorTypes.h
index 28b7946bdec..e8cc51832bf 100644
--- a/MathLib/LinAlg/GlobalMatrixVectorTypes.h
+++ b/MathLib/LinAlg/GlobalMatrixVectorTypes.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATHLIB_LINALG_GLOBALMATRIXVECTORTYPES_H
-#define MATHLIB_LINALG_GLOBALMATRIXVECTORTYPES_H
+#pragma once
 
 #include "SparsityPattern.h"
 
@@ -62,5 +61,3 @@ static_assert(std::is_same<GlobalMatrix::IndexType,
 using GlobalIndexType = GlobalMatrix::IndexType;
 
 using GlobalSparsityPattern = MathLib::SparsityPattern<GlobalIndexType>;
-
-#endif // MATHLIB_LINALG_GLOBALMATRIXVECTORTYPES_H
diff --git a/MathLib/LinAlg/LinAlg.h b/MathLib/LinAlg/LinAlg.h
index 823bcda1ba2..06388524bce 100644
--- a/MathLib/LinAlg/LinAlg.h
+++ b/MathLib/LinAlg/LinAlg.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATHLIB_LINALG_H
-#define MATHLIB_LINALG_H
+#pragma once
 
 #include <cassert>
 #include "BaseLib/Error.h"
@@ -253,5 +252,3 @@ void finalizeAssembly(EigenMatrix& A);
 } // namespace MathLib
 
 #endif
-
-#endif // MATHLIB_LINALG_H
diff --git a/MathLib/LinAlg/LinAlgEnums.h b/MathLib/LinAlg/LinAlgEnums.h
index cd40fad8272..c63992c30e1 100644
--- a/MathLib/LinAlg/LinAlgEnums.h
+++ b/MathLib/LinAlg/LinAlgEnums.h
@@ -9,8 +9,7 @@
  *
  */
 
-#ifndef LINALGENUMS_H_
-#define LINALGENUMS_H_
+#pragma once
 
 #include <string>
 
@@ -33,5 +32,3 @@ std::string convertVecNormTypeToString(VecNormType normType);
 VecNormType convertStringToVecNormType(const std::string &str);
 
 } // end namespace MathLib
-
-#endif /* LINALGENUMS_H_ */
diff --git a/MathLib/LinAlg/LinearSolverOptions.h b/MathLib/LinAlg/LinearSolverOptions.h
index 7fb07b42a7b..d15f4627d38 100644
--- a/MathLib/LinAlg/LinearSolverOptions.h
+++ b/MathLib/LinAlg/LinearSolverOptions.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATHLIB_LINEAR_SOLVER_OPTIONS_H
-#define MATHLIB_LINEAR_SOLVER_OPTIONS_H
+#pragma once
 
 #include "BaseLib/ConfigTree.h"
 
@@ -37,5 +36,3 @@ void ignoreOtherLinearSolvers(BaseLib::ConfigTree const& config,
                               std::string const& solver_name);
 
 }
-
-#endif
diff --git a/MathLib/LinAlg/Lis/LisCheck.h b/MathLib/LinAlg/Lis/LisCheck.h
index 744f1a66d6a..1def988c422 100644
--- a/MathLib/LinAlg/Lis/LisCheck.h
+++ b/MathLib/LinAlg/Lis/LisCheck.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef LISCHECK_H_
-#define LISCHECK_H_
+#pragma once
 
 #include <vector>
 #include "lis.h"
@@ -38,6 +37,3 @@ inline bool checkLisError(int err)
 }
 
 } // MathLib
-
-#endif //LISCHECK_H_
-
diff --git a/MathLib/LinAlg/Lis/LisLinearSolver.h b/MathLib/LinAlg/Lis/LisLinearSolver.h
index 740937e84f0..f5801a40233 100644
--- a/MathLib/LinAlg/Lis/LisLinearSolver.h
+++ b/MathLib/LinAlg/Lis/LisLinearSolver.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef LISLINEARSOLVER_H_
-#define LISLINEARSOLVER_H_
+#pragma once
 
 #include <vector>
 #include <string>
@@ -61,6 +60,3 @@ private:
 };
 
 } // MathLib
-
-#endif //LISLINEARSOLVER_H_
-
diff --git a/MathLib/LinAlg/Lis/LisMatrix.h b/MathLib/LinAlg/Lis/LisMatrix.h
index c2e4d0d36de..05b7042a352 100644
--- a/MathLib/LinAlg/Lis/LisMatrix.h
+++ b/MathLib/LinAlg/Lis/LisMatrix.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef LISMATRIX_H_
-#define LISMATRIX_H_
+#pragma once
 
 #include <string>
 #include <vector>
@@ -207,5 +206,3 @@ void operator()(LisMatrix &matrix, SPARSITY_PATTERN const& sparsity_pattern)
 
 
 } // MathLib
-
-#endif //LISMATRIX_H_
diff --git a/MathLib/LinAlg/Lis/LisOption.h b/MathLib/LinAlg/Lis/LisOption.h
index eefad7b2085..c669db7874c 100644
--- a/MathLib/LinAlg/Lis/LisOption.h
+++ b/MathLib/LinAlg/Lis/LisOption.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef LIS_OPTION_H_
-#define LIS_OPTION_H_
+#pragma once
 
 #include <string>
 #include <map>
@@ -58,4 +57,3 @@ struct LisOption
 
 };
 }
-#endif  // LIS_OPTION_H_
diff --git a/MathLib/LinAlg/Lis/LisVector.h b/MathLib/LinAlg/Lis/LisVector.h
index 27b7a6b4738..12b52d00c19 100644
--- a/MathLib/LinAlg/Lis/LisVector.h
+++ b/MathLib/LinAlg/Lis/LisVector.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef LISVECTOR_H_
-#define LISVECTOR_H_
+#pragma once
 
 #include <string>
 #include <vector>
@@ -112,5 +111,3 @@ private:
 };
 
 }  // MathLib
-
-#endif  // LISVECTOR_H_
diff --git a/MathLib/LinAlg/MatrixSpecifications.h b/MathLib/LinAlg/MatrixSpecifications.h
index 9722b2e1383..4e5f01add20 100644
--- a/MathLib/LinAlg/MatrixSpecifications.h
+++ b/MathLib/LinAlg/MatrixSpecifications.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATHLIB_LINALG_MATRIXSPECIFICATIONS_H
-#define MATHLIB_LINALG_MATRIXSPECIFICATIONS_H
+#pragma once
 
 #include "GlobalMatrixVectorTypes.h"
 
@@ -32,6 +31,3 @@ struct MatrixSpecifications
 };
 
 } // namespace MathLib
-
-
-#endif // MATHLIB_LINALG_MATRIXSPECIFICATIONS_H
diff --git a/MathLib/LinAlg/MatrixVectorTraits.h b/MathLib/LinAlg/MatrixVectorTraits.h
index 464fe9da5c1..2dd95190cc6 100644
--- a/MathLib/LinAlg/MatrixVectorTraits.h
+++ b/MathLib/LinAlg/MatrixVectorTraits.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATHLIB_MATRIX_VECTOR_TRAITS_H
-#define MATHLIB_MATRIX_VECTOR_TRAITS_H
+#pragma once
 
 #include <memory>
 #include "MatrixSpecifications.h"
@@ -54,5 +53,3 @@ SPECIALIZE_MATRIX_VECTOR_TRAITS(EigenVector, EigenVector::IndexType)
 #endif
 
 #undef SPECIALIZE_MATRIX_VECTOR_TRAITS
-
-#endif // MATHLIB_MATRIX_VECTOR_TRAITS_H
diff --git a/MathLib/LinAlg/PETSc/PETScLinearSolver.h b/MathLib/LinAlg/PETSc/PETScLinearSolver.h
index b9dd1abc43d..d3c69583775 100644
--- a/MathLib/LinAlg/PETSc/PETScLinearSolver.h
+++ b/MathLib/LinAlg/PETSc/PETScLinearSolver.h
@@ -14,8 +14,7 @@
                http://www.opengeosys.org/project/license
 */
 
-#ifndef PETSCLINEARSOLVER_H_
-#define PETSCLINEARSOLVER_H_
+#pragma once
 
 #include<string>
 
@@ -83,5 +82,3 @@ class PETScLinearSolver
 };
 
 } // end namespace
-#endif
-
diff --git a/MathLib/LinAlg/PETSc/PETScMatrix.h b/MathLib/LinAlg/PETSc/PETScMatrix.h
index 34f01030676..50b623fa3d1 100644
--- a/MathLib/LinAlg/PETSc/PETScMatrix.h
+++ b/MathLib/LinAlg/PETSc/PETScMatrix.h
@@ -12,8 +12,7 @@
                See accompanying file LICENSE.txt or
                http://www.opengeosys.org/project/license
 */
-#ifndef PETSCMATRIX_H_
-#define PETSCMATRIX_H_
+#pragma once
 
 #include <string>
 #include <vector>
@@ -287,5 +286,3 @@ void PETScMatrix::add(std::vector<PetscInt> const& row_pos,
 bool finalizeMatrixAssembly(PETScMatrix &mat, const MatAssemblyType asm_type = MAT_FINAL_ASSEMBLY);
 
 } // end namespace
-#endif
-
diff --git a/MathLib/LinAlg/PETSc/PETScMatrixOption.h b/MathLib/LinAlg/PETSc/PETScMatrixOption.h
index 72c10c72d60..66a6750cc4c 100644
--- a/MathLib/LinAlg/PETSc/PETScMatrixOption.h
+++ b/MathLib/LinAlg/PETSc/PETScMatrixOption.h
@@ -11,8 +11,7 @@
                See accompanying file LICENSE.txt or
                http://www.opengeosys.org/project/license
 */
-#ifndef PETSCMATRIXOPTION_H_
-#define PETSCMATRIXOPTION_H_
+#pragma once
 
 #include <petscmat.h>
 
@@ -53,5 +52,3 @@ struct PETScMatrixOption
 };
 
 } // end namespace
-#endif
-
diff --git a/MathLib/LinAlg/PETSc/PETScTools.h b/MathLib/LinAlg/PETSc/PETScTools.h
index fe771e9b23f..9c0a20db04a 100644
--- a/MathLib/LinAlg/PETSc/PETScTools.h
+++ b/MathLib/LinAlg/PETSc/PETScTools.h
@@ -14,8 +14,7 @@
                http://www.opengeosys.org/project/license
 */
 
-#ifndef PETSCTOOLS_H_
-#define PETSCTOOLS_H_
+#pragma once
 
 #include <vector>
 
@@ -37,6 +36,3 @@ void applyKnownSolution(PETScMatrix &A, PETScVector &b, PETScVector &x,
                         const std::vector<PetscInt> &vec_knownX_id,
                         const std::vector<PetscScalar> &vec_knownX_x);
 } // end of namespace MathLib
-
-#endif //end  of PETSCTOOLS_H_
-
diff --git a/MathLib/LinAlg/PETSc/PETScVector.h b/MathLib/LinAlg/PETSc/PETScVector.h
index befe4c014af..cba4692313e 100644
--- a/MathLib/LinAlg/PETSc/PETScVector.h
+++ b/MathLib/LinAlg/PETSc/PETScVector.h
@@ -14,8 +14,7 @@
  *
  */
 
-#ifndef PETSCVECTOR_H_
-#define PETSCVECTOR_H_
+#pragma once
 
 #include <string>
 #include <vector>
@@ -301,4 +300,3 @@ class PETScVector
 void finalizeVectorAssembly(PETScVector &vec);
 
 } // end namespace
-#endif
diff --git a/MathLib/LinAlg/RowColumnIndices.h b/MathLib/LinAlg/RowColumnIndices.h
index 0bd03719c61..f75587cf00a 100644
--- a/MathLib/LinAlg/RowColumnIndices.h
+++ b/MathLib/LinAlg/RowColumnIndices.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef ROWCOLUMNINDICES_H_
-#define ROWCOLUMNINDICES_H_
+#pragma once
 
 #include <vector>
 
@@ -28,5 +27,3 @@ struct RowColumnIndices
 };
 
 } // MathLib
-
-#endif  // ROWCOLUMNINDICES_H_
diff --git a/MathLib/LinAlg/SetMatrixSparsity.h b/MathLib/LinAlg/SetMatrixSparsity.h
index fe6dd7f360b..cc9bf655f87 100644
--- a/MathLib/LinAlg/SetMatrixSparsity.h
+++ b/MathLib/LinAlg/SetMatrixSparsity.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef MATHLIB_SETMATRIXSPARSITY_H_
-#define MATHLIB_SETMATRIXSPARSITY_H_
+#pragma once
 
 namespace MathLib
 {
@@ -41,5 +40,3 @@ void setMatrixSparsity(MATRIX& matrix, SPARSITY_PATTERN const& sparsity_pattern)
 #ifdef OGS_USE_EIGEN
 #include "Eigen/EigenMatrix.h"
 #endif  // OGS_USE_EIGEN
-
-#endif  // MATHLIB_SETMATRIXSPARSITY_H_
diff --git a/MathLib/LinAlg/Solvers/GaussAlgorithm.h b/MathLib/LinAlg/Solvers/GaussAlgorithm.h
index e8b14c53588..dbe67099bad 100644
--- a/MathLib/LinAlg/Solvers/GaussAlgorithm.h
+++ b/MathLib/LinAlg/Solvers/GaussAlgorithm.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef GAUSSALGORITHM_H_
-#define GAUSSALGORITHM_H_
+#pragma once
 
 #include <vector>
 
@@ -100,5 +99,3 @@ private:
 } // end namespace MathLib
 
 #include "GaussAlgorithm-impl.h"
-
-#endif /* GAUSSALGORITHM_H_ */
diff --git a/MathLib/LinAlg/Solvers/TriangularSolve.h b/MathLib/LinAlg/Solvers/TriangularSolve.h
index f358c4258b4..51543ce397f 100644
--- a/MathLib/LinAlg/Solvers/TriangularSolve.h
+++ b/MathLib/LinAlg/Solvers/TriangularSolve.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef TRIANGULARSOLVE_H_
-#define TRIANGULARSOLVE_H_
+#pragma once
 
 #include "../Dense/DenseMatrix.h"
 
@@ -51,5 +50,3 @@ void backwardSolve ( DenseMatrix<FP_T> const& mat, VEC_T& x, VEC_T const& b);
 } // end namespace MathLib
 
 #include "TriangularSolve-impl.h"
-
-#endif /* TRIANGULARSOLVE_H_ */
diff --git a/MathLib/LinAlg/SparsityPattern.h b/MathLib/LinAlg/SparsityPattern.h
index 64f23285296..92089345dc6 100644
--- a/MathLib/LinAlg/SparsityPattern.h
+++ b/MathLib/LinAlg/SparsityPattern.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATHLIB_LINALG_SPARSITYPATTERN_H
-#define MATHLIB_LINALG_SPARSITYPATTERN_H
+#pragma once
 
 #include <vector>
 
@@ -18,5 +17,3 @@ namespace MathLib
 template <typename IndexType>
 using SparsityPattern = std::vector<IndexType>;
 }
-
-#endif // MATHLIB_LINALG_SPARSITYPATTERN_H
diff --git a/MathLib/LinAlg/UnifiedMatrixSetters.h b/MathLib/LinAlg/UnifiedMatrixSetters.h
index 2afcd8e4d00..7ee46580129 100644
--- a/MathLib/LinAlg/UnifiedMatrixSetters.h
+++ b/MathLib/LinAlg/UnifiedMatrixSetters.h
@@ -9,8 +9,7 @@
 
 // TODO merge that with MatrixVectorTraits?
 
-#ifndef MATHLIB_UNIFIED_MATRIX_SETTERS_H
-#define MATHLIB_UNIFIED_MATRIX_SETTERS_H
+#pragma once
 
 #include <initializer_list>
 #include <Eigen/Core>
@@ -69,5 +68,3 @@ void addToMatrix(EigenMatrix& m,
 } // namespace MathLib
 
 #endif // OGS_USE_EIGEN
-
-#endif // MATHLIB_UNIFIED_MATRIX_SETTERS_H
diff --git a/MathLib/LinearFunction.h b/MathLib/LinearFunction.h
index 402b072f0db..1d5b593fc20 100644
--- a/MathLib/LinearFunction.h
+++ b/MathLib/LinearFunction.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef LINEARFUNCTION_H_
-#define LINEARFUNCTION_H_
+#pragma once
 
 #include <array>
 #include <numeric>
@@ -56,5 +55,3 @@ private:
 };
 
 } // MathLib
-
-#endif /* LINEARFUNCTION_H_ */
diff --git a/MathLib/MathTools.h b/MathLib/MathTools.h
index bb074813801..627854e7939 100644
--- a/MathLib/MathTools.h
+++ b/MathLib/MathTools.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef MATHTOOLS_H_
-#define MATHTOOLS_H_
+#pragma once
 
 #include <cstddef>
 
@@ -131,5 +130,3 @@ template<typename Type> Type limitValueInInterval(const Type variable,
     return variable;
 }
 } // namespace
-
-#endif /* MATHTOOLS_H_ */
diff --git a/MathLib/Nonlinear/Root1D.h b/MathLib/Nonlinear/Root1D.h
index 53a2d1449d6..7b60212e875 100644
--- a/MathLib/Nonlinear/Root1D.h
+++ b/MathLib/Nonlinear/Root1D.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATHLIB_NONLINEAR_ROOT1D_H
-#define MATHLIB_NONLINEAR_ROOT1D_H
+#pragma once
 
 #include <cassert>
 #include <cmath>
@@ -161,5 +160,3 @@ struct AndersonBjorck
 }
 
 } // namespace MathLib
-
-#endif // MATHLIB_NONLINEAR_ROOT1D_H
diff --git a/MathLib/ODE/CVodeSolver.h b/MathLib/ODE/CVodeSolver.h
index a7ecd364bb1..7bb43b1b3f0 100644
--- a/MathLib/ODE/CVodeSolver.h
+++ b/MathLib/ODE/CVodeSolver.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATHLIB_CVODESOLVER_H
-#define MATHLIB_CVODESOLVER_H
+#pragma once
 
 #include <memory>
 
@@ -77,5 +76,3 @@ private:
 
 }  // namespace ODE
 }  // namespace MathLib
-
-#endif  // MATHLIB_CVODESOLVER_H
diff --git a/MathLib/ODE/ConcreteODESolver.h b/MathLib/ODE/ConcreteODESolver.h
index 8ac107be7a4..ae688d88b2e 100644
--- a/MathLib/ODE/ConcreteODESolver.h
+++ b/MathLib/ODE/ConcreteODESolver.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATHLIB_ODE_CONCRETEODESOLVER_H
-#define MATHLIB_ODE_CONCRETEODESOLVER_H
+#pragma once
 
 #include <memory>
 
@@ -119,5 +118,3 @@ private:
 
 }  // namespace ODE
 }  // namespace MathLib
-
-#endif  // MATHLIB_ODE_CONCRETEODESOLVER_H
diff --git a/MathLib/ODE/FunctionHandles.h b/MathLib/ODE/FunctionHandles.h
index 4eae69697d6..b4df79f6c86 100644
--- a/MathLib/ODE/FunctionHandles.h
+++ b/MathLib/ODE/FunctionHandles.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATHLIB_ODE_HANDLES_H
-#define MATHLIB_ODE_HANDLES_H
+#pragma once
 
 #include "ODESolverTypes.h"
 
@@ -111,5 +110,3 @@ struct FunctionHandlesImpl final : public FunctionHandles
 }  // namespace detail
 }  // namespace ODE
 }  // namespace MathLib
-
-#endif  // MATHLIB_ODE_HANDLES_H
diff --git a/MathLib/ODE/ODESolver.h b/MathLib/ODE/ODESolver.h
index d651ce6c25a..463ab373889 100644
--- a/MathLib/ODE/ODESolver.h
+++ b/MathLib/ODE/ODESolver.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATHLIB_ODESOLVER_H
-#define MATHLIB_ODESOLVER_H
+#pragma once
 
 #include <array>
 
@@ -136,5 +135,3 @@ public:
 
 }  // namespace ODE
 }  // namespace MathLib
-
-#endif  // MATHLIB_ODESOLVER_H
diff --git a/MathLib/ODE/ODESolverBuilder.h b/MathLib/ODE/ODESolverBuilder.h
index 62b2813384d..04b9078ef03 100644
--- a/MathLib/ODE/ODESolverBuilder.h
+++ b/MathLib/ODE/ODESolverBuilder.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATHLIB_ODE_ODESOLVERBUILDER_H
-#define MATHLIB_ODE_ODESOLVERBUILDER_H
+#pragma once
 
 #include <logog/include/logog.hpp>
 
@@ -55,5 +54,3 @@ std::unique_ptr<ODESolver<NumEquations>> createODESolver(
 
 }  // namespace ODE
 }  // namespace MathLib
-
-#endif  // MATHLIB_ODE_ODESOLVERBUILDER_H
diff --git a/MathLib/ODE/ODESolverTypes.h b/MathLib/ODE/ODESolverTypes.h
index 84e426b4353..487bbbf6f47 100644
--- a/MathLib/ODE/ODESolverTypes.h
+++ b/MathLib/ODE/ODESolverTypes.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MATHLIB_ODE_ODESOLVERTYPES_H
-#define MATHLIB_ODE_ODESOLVERTYPES_H
+#pragma once
 
 #include <functional>
 #include <Eigen/Core>
@@ -70,5 +69,3 @@ using JacobianFunction = std::function<bool(const double t,
 
 }  // namespace ODE
 }  // namespace MathLib
-
-#endif  // MATHLIB_ODE_ODESOLVERTYPES_H
diff --git a/MathLib/Point3d.h b/MathLib/Point3d.h
index e218c6c90b7..f8a4cda77e2 100644
--- a/MathLib/Point3d.h
+++ b/MathLib/Point3d.h
@@ -11,8 +11,7 @@
  *
  */
 
-#ifndef POINT3D_H_
-#define POINT3D_H_
+#pragma once
 
 #include <limits>
 
@@ -60,6 +59,3 @@ double sqrDist2d(MathLib::Point3d const& p0, MathLib::Point3d const& p1)
 }
 
 } // end namespace MathLib
-
-#endif /* POINT3D_H_ */
-
diff --git a/MathLib/Point3dWithID.h b/MathLib/Point3dWithID.h
index a8b8c0a5021..8a9cc335421 100644
--- a/MathLib/Point3dWithID.h
+++ b/MathLib/Point3dWithID.h
@@ -11,8 +11,7 @@
  *
  */
 
-#ifndef POINT3DWITHID_H_
-#define POINT3DWITHID_H_
+#pragma once
 
 #include <limits>
 
@@ -68,6 +67,3 @@ protected:
 };
 
 }
-
-#endif /* POINT3DWITHID_H_ */
-
diff --git a/MathLib/TemplatePoint.h b/MathLib/TemplatePoint.h
index 5e16c18a16a..92bc97d107f 100644
--- a/MathLib/TemplatePoint.h
+++ b/MathLib/TemplatePoint.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef TEMPLATEPOINT_H_
-#define TEMPLATEPOINT_H_
+#pragma once
 
 // STL
 #include <array>
@@ -199,5 +198,3 @@ std::istream& operator>> (std::istream &is, TemplatePoint<T,DIM> &p)
     return is;
 }
 } // end namespace MathLib
-
-#endif /* TEMPLATEPOINT_H_ */
diff --git a/MathLib/TemplateWeightedPoint.h b/MathLib/TemplateWeightedPoint.h
index 351754e8faa..318566c1980 100644
--- a/MathLib/TemplateWeightedPoint.h
+++ b/MathLib/TemplateWeightedPoint.h
@@ -10,8 +10,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef TEMPLATEWEIGHTEDPOINT_H_
-#define TEMPLATEWEIGHTEDPOINT_H_
+#pragma once
 
 #include "TemplatePoint.h"
 
@@ -40,6 +39,3 @@ typedef TemplateWeightedPoint<double, double, 2> WeightedPoint2D;
 typedef TemplateWeightedPoint<double, double, 3> WeightedPoint3D;
 
 } // end namespace MathLib
-
-
-#endif /* TEMPLATEWEIGHTEDPOINT_H_ */
diff --git a/MathLib/Vector3.h b/MathLib/Vector3.h
index af1d1d4362b..e880b55a6a6 100644
--- a/MathLib/Vector3.h
+++ b/MathLib/Vector3.h
@@ -14,8 +14,7 @@
  *
  */
 
-#ifndef VECTOR3_H
-#define VECTOR3_H
+#pragma once
 
 #include <cmath>
 
@@ -193,5 +192,3 @@ double scalarTriple(MathLib::Vector3 const& u, MathLib::Vector3 const& v,
                     MathLib::Vector3 const& w);
 
 }
-
-#endif // VECTOR3_H
diff --git a/MeshGeoToolsLib/AppendLinesAlongPolyline.h b/MeshGeoToolsLib/AppendLinesAlongPolyline.h
index 828f98b3164..0940c886af3 100644
--- a/MeshGeoToolsLib/AppendLinesAlongPolyline.h
+++ b/MeshGeoToolsLib/AppendLinesAlongPolyline.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef APPENDLINESALONGPOLYLINES_H_
-#define APPENDLINESALONGPOLYLINES_H_
+#pragma once
 
 #include <memory>
 
@@ -42,5 +41,3 @@ namespace MeshGeoToolsLib
 std::unique_ptr<MeshLib::Mesh> appendLinesAlongPolylines(
     const MeshLib::Mesh& mesh, const GeoLib::PolylineVec& ply_vec);
 }
-
-#endif
diff --git a/MeshGeoToolsLib/BoundaryElementsAlongPolyline.h b/MeshGeoToolsLib/BoundaryElementsAlongPolyline.h
index 355937494e1..677efacccab 100644
--- a/MeshGeoToolsLib/BoundaryElementsAlongPolyline.h
+++ b/MeshGeoToolsLib/BoundaryElementsAlongPolyline.h
@@ -5,8 +5,7 @@
  *              See accompanying file LICENSE.txt or
  *              http://www.opengeosys.org/LICENSE.txt
  */
-#ifndef BOUNDARYELEMENTSALONGPOLYLINE_H_
-#define BOUNDARYELEMENTSALONGPOLYLINE_H_
+#pragma once
 
 #include <vector>
 
@@ -85,5 +84,3 @@ private:
 };
 
 } // end namespace MeshGeoToolsLib
-
-#endif /* BOUNDARYELEMENTSALONGPOLYLINE_H_ */
diff --git a/MeshGeoToolsLib/BoundaryElementsAtPoint.h b/MeshGeoToolsLib/BoundaryElementsAtPoint.h
index 77010872572..9e4b843bded 100644
--- a/MeshGeoToolsLib/BoundaryElementsAtPoint.h
+++ b/MeshGeoToolsLib/BoundaryElementsAtPoint.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef BOUNDARYELEMENTSATPOINT_H_
-#define BOUNDARYELEMENTSATPOINT_H_
+#pragma once
 
 #include <vector>
 
@@ -64,5 +63,3 @@ private:
 };
 
 }  // end namespace MeshGeoToolsLib
-
-#endif  // BOUNDARYELEMENTSATPOINT_H_
diff --git a/MeshGeoToolsLib/BoundaryElementsOnSurface.h b/MeshGeoToolsLib/BoundaryElementsOnSurface.h
index 5cfc2dd14c8..f4e31f8f3da 100644
--- a/MeshGeoToolsLib/BoundaryElementsOnSurface.h
+++ b/MeshGeoToolsLib/BoundaryElementsOnSurface.h
@@ -5,8 +5,7 @@
  *              See accompanying file LICENSE.txt or
  *              http://www.opengeosys.org/LICENSE.txt
  */
-#ifndef BOUNDARYELEMENTSONSURFACE_H_
-#define BOUNDARYELEMENTSONSURFACE_H_
+#pragma once
 
 #include <vector>
 
@@ -65,5 +64,3 @@ private:
 };
 
 } // end namespace MeshGeoToolsLib
-
-#endif /* BOUNDARYELEMENTSONSURFACE_H_ */
diff --git a/MeshGeoToolsLib/BoundaryElementsSearcher.h b/MeshGeoToolsLib/BoundaryElementsSearcher.h
index 8636a0c80ad..ad2d66ef262 100644
--- a/MeshGeoToolsLib/BoundaryElementsSearcher.h
+++ b/MeshGeoToolsLib/BoundaryElementsSearcher.h
@@ -5,8 +5,7 @@
  *              See accompanying file LICENSE.txt or
  *              http://www.opengeosys.org/LICENSE.txt
  */
-#ifndef BOUNDARYELEMENTSSEARCHER_H_
-#define BOUNDARYELEMENTSSEARCHER_H_
+#pragma once
 
 #include <vector>
 
@@ -87,5 +86,3 @@ private:
 };
 
 } // end namespace MeshGeoToolsLib
-
-#endif /* BOUNDARYELEMENTSSEARCHER_H_ */
diff --git a/MeshGeoToolsLib/GeoMapper.h b/MeshGeoToolsLib/GeoMapper.h
index 795bb0f465a..35b348f405e 100644
--- a/MeshGeoToolsLib/GeoMapper.h
+++ b/MeshGeoToolsLib/GeoMapper.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef GEOMAPPER_H
-#define GEOMAPPER_H
+#pragma once
 
 #include <cstddef>
 #include <vector>
@@ -95,5 +94,3 @@ private:
 };
 
 } // end namespace MeshGeoToolsLib
-
-#endif //GEOMAPPER_H
diff --git a/MeshGeoToolsLib/HeuristicSearchLength.h b/MeshGeoToolsLib/HeuristicSearchLength.h
index 0d8a57d84d2..79bbf6a8234 100644
--- a/MeshGeoToolsLib/HeuristicSearchLength.h
+++ b/MeshGeoToolsLib/HeuristicSearchLength.h
@@ -9,8 +9,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef HEURISTICSEARCHLENGTH_H_
-#define HEURISTICSEARCHLENGTH_H_
+#pragma once
 
 #include "MeshGeoToolsLib/SearchLength.h"
 
@@ -50,6 +49,3 @@ private:
 };
 
 } // end namespace MeshGeoToolsLib
-
-#endif
-
diff --git a/MeshGeoToolsLib/MeshNodeSearcher.h b/MeshGeoToolsLib/MeshNodeSearcher.h
index f2ab2358ef4..fdd432e4039 100644
--- a/MeshGeoToolsLib/MeshNodeSearcher.h
+++ b/MeshGeoToolsLib/MeshNodeSearcher.h
@@ -7,8 +7,7 @@
  *              See accompanying file LICENSE.txt or
  *              http://www.opengeosys.org/LICENSE.txt
  */
-#ifndef MESHNODESEARCHER_H_
-#define MESHNODESEARCHER_H_
+#pragma once
 
 #include <memory>
 #include <vector>
@@ -151,5 +150,3 @@ private:
 };
 
 } // end namespace MeshGeoToolsLib
-
-#endif /* MESHNODESEARCHER_H_ */
diff --git a/MeshGeoToolsLib/MeshNodesAlongPolyline.h b/MeshGeoToolsLib/MeshNodesAlongPolyline.h
index 3875cb4ce30..e90ed01458a 100644
--- a/MeshGeoToolsLib/MeshNodesAlongPolyline.h
+++ b/MeshGeoToolsLib/MeshNodesAlongPolyline.h
@@ -10,8 +10,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef MESHNODESALONGPOLYLINE_H_
-#define MESHNODESALONGPOLYLINE_H_
+#pragma once
 
 #include <vector>
 
@@ -77,5 +76,3 @@ private:
     std::vector<double> _dist_of_proj_node_from_ply_start;
 };
 } // end namespace MeshGeoToolsLib
-
-#endif /* MESHNODESALONGPOLYLINE_H_ */
diff --git a/MeshGeoToolsLib/MeshNodesAlongSurface.h b/MeshGeoToolsLib/MeshNodesAlongSurface.h
index 91aea451bea..c8a1c85b266 100644
--- a/MeshGeoToolsLib/MeshNodesAlongSurface.h
+++ b/MeshGeoToolsLib/MeshNodesAlongSurface.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef MESHNODESALONGSURFACE_H_
-#define MESHNODESALONGSURFACE_H_
+#pragma once
 
 #include <vector>
 
@@ -69,5 +68,3 @@ private:
     std::vector<std::size_t> _msh_node_ids;
 };
 } // end namespace MeshGeoToolsLib
-
-#endif /* MESHNODESALONGSURFACE_H_ */
diff --git a/MeshGeoToolsLib/MeshNodesOnPoint.h b/MeshGeoToolsLib/MeshNodesOnPoint.h
index da669243153..11b5b477293 100644
--- a/MeshGeoToolsLib/MeshNodesOnPoint.h
+++ b/MeshGeoToolsLib/MeshNodesOnPoint.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef MESHNODESONPOINT_H_
-#define MESHNODESONPOINT_H_
+#pragma once
 
 #include <vector>
 
@@ -63,5 +62,3 @@ private:
     std::vector<std::size_t> _msh_node_ids;
 };
 } // end namespace MeshGeoToolsLib
-
-#endif /* MESHNODESONPOINT_H_ */
diff --git a/MeshGeoToolsLib/SearchLength.h b/MeshGeoToolsLib/SearchLength.h
index 4b8877ab50e..8b72d59be71 100644
--- a/MeshGeoToolsLib/SearchLength.h
+++ b/MeshGeoToolsLib/SearchLength.h
@@ -9,8 +9,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef SEARCHLENGTH_H_
-#define SEARCHLENGTH_H_
+#pragma once
 
 namespace MeshGeoToolsLib
 {
@@ -42,6 +41,3 @@ protected:
 };
 
 } // end namespace MeshGeoToolsLib
-
-#endif
-
diff --git a/MeshLib/CoordinateSystem.h b/MeshLib/CoordinateSystem.h
index d2e2b9c5f61..f8ed88db0b4 100644
--- a/MeshLib/CoordinateSystem.h
+++ b/MeshLib/CoordinateSystem.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef COORDINATESYSTEMTYPE_H_
-#define COORDINATESYSTEMTYPE_H_
+#pragma once
 
 #include <cmath>
 
@@ -78,5 +77,3 @@ private:
 };
 
 } // MeshLib
-
-#endif // COORDINATESYSTEMTYPE_H_
diff --git a/MeshLib/ElementCoordinatesMappingLocal.h b/MeshLib/ElementCoordinatesMappingLocal.h
index 6b4c8ffcc0d..3185b911f3c 100644
--- a/MeshLib/ElementCoordinatesMappingLocal.h
+++ b/MeshLib/ElementCoordinatesMappingLocal.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef ELEMENTCOORDINATESMAPPINGLOCAL_H_
-#define ELEMENTCOORDINATESMAPPINGLOCAL_H_
+#pragma once
 
 #include <vector>
 #include <Eigen/Eigen>
@@ -54,5 +53,3 @@ private:
 };
 
 }
-
-#endif // ELEMENTCOORDINATESMAPPINGLOCAL_H_
diff --git a/MeshLib/ElementStatus.h b/MeshLib/ElementStatus.h
index 2240dfeb955..3ca2a5b99d8 100644
--- a/MeshLib/ElementStatus.h
+++ b/MeshLib/ElementStatus.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef ELEMENTSTATUS_H_
-#define ELEMENTSTATUS_H_
+#pragma once
 
 #include <vector>
 
@@ -73,5 +72,3 @@ protected:
 }; /* class */
 
 } /* namespace */
-
-#endif /* ELEMENTSTATUS_H_ */
diff --git a/MeshLib/Elements/CellRule.h b/MeshLib/Elements/CellRule.h
index 02a178b762c..620dd224122 100644
--- a/MeshLib/Elements/CellRule.h
+++ b/MeshLib/Elements/CellRule.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef CELLRULE_H_
-#define CELLRULE_H_
+#pragma once
 
 namespace MeshLib
 {
@@ -33,6 +32,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* CELLRULE_H_ */
-
diff --git a/MeshLib/Elements/EdgeReturn.h b/MeshLib/Elements/EdgeReturn.h
index 74a5b85272e..db3f5ba298c 100644
--- a/MeshLib/Elements/EdgeReturn.h
+++ b/MeshLib/Elements/EdgeReturn.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef EDGERETURN_H_
-#define EDGERETURN_H_
+#pragma once
 
 namespace MeshLib
 {
@@ -43,7 +42,3 @@ public:
 };
 
 } // end MeshLib
-
-
-#endif /* EDGERETURN_H_ */
-
diff --git a/MeshLib/Elements/EdgeRule.h b/MeshLib/Elements/EdgeRule.h
index b5325e3df0a..9a9884e362f 100644
--- a/MeshLib/Elements/EdgeRule.h
+++ b/MeshLib/Elements/EdgeRule.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef EDGERULE_H_
-#define EDGERULE_H_
+#pragma once
 
 namespace MeshLib
 {
@@ -39,6 +38,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* EDGERULE_H_ */
-
diff --git a/MeshLib/Elements/Element.h b/MeshLib/Elements/Element.h
index a4b2a5c56cb..1aefc52267a 100644
--- a/MeshLib/Elements/Element.h
+++ b/MeshLib/Elements/Element.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef ELEMENT_H_
-#define ELEMENT_H_
+#pragma once
 
 #include <limits>
 #include <boost/optional.hpp>
@@ -232,6 +231,3 @@ protected:
 bool isPointInElementXY(MathLib::Point3d const& p, Element const& e);
 
 } /* namespace */
-
-#endif /* ELEMENT_H_ */
-
diff --git a/MeshLib/Elements/ElementErrorCode.h b/MeshLib/Elements/ElementErrorCode.h
index b468137129c..ac284ae897b 100644
--- a/MeshLib/Elements/ElementErrorCode.h
+++ b/MeshLib/Elements/ElementErrorCode.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef ELEMENTERRORCODES_H
-#define ELEMENTERRORCODES_H
+#pragma once
 
 #include <bitset>
 #include <string>
@@ -61,6 +60,3 @@ public:
 private:
 
 };
-
-
-#endif //ELEMENTERRORCODES_H
diff --git a/MeshLib/Elements/Elements.h b/MeshLib/Elements/Elements.h
index 718c95ec5fd..9e9ecbe6e19 100644
--- a/MeshLib/Elements/Elements.h
+++ b/MeshLib/Elements/Elements.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef MESHLIB_ELEMENTS_ELEMENTS_H_
-#define MESHLIB_ELEMENTS_ELEMENTS_H_
+#pragma once
 
 #include "MeshLib/Elements/Element.h"
 #include "MeshLib/Elements/Line.h"
@@ -22,5 +21,3 @@
 #include "MeshLib/Elements/Quad.h"
 #include "MeshLib/Elements/Tet.h"
 #include "MeshLib/Elements/Tri.h"
-
-#endif  // MESHLIB_ELEMENTS_ELEMENTS_H_
diff --git a/MeshLib/Elements/FaceRule.h b/MeshLib/Elements/FaceRule.h
index 21d45df77b5..45c5970ec4a 100644
--- a/MeshLib/Elements/FaceRule.h
+++ b/MeshLib/Elements/FaceRule.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef FACERULE_H_
-#define FACERULE_H_
+#pragma once
 
 #include "MathLib/Vector3.h"
 #include "Element.h"
@@ -40,6 +39,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* FACERULE_H_ */
-
diff --git a/MeshLib/Elements/Hex.h b/MeshLib/Elements/Hex.h
index 751646b3674..9bb14dc6ab0 100644
--- a/MeshLib/Elements/Hex.h
+++ b/MeshLib/Elements/Hex.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef HEX_H_
-#define HEX_H_
+#pragma once
 
 #include "TemplateElement.h"
 #include "HexRule8.h"
@@ -26,5 +25,3 @@ namespace MeshLib {
 typedef TemplateElement<HexRule8> Hex;
 typedef TemplateElement<HexRule20> Hex20;
 }
-
-#endif /* HEX_H_ */
diff --git a/MeshLib/Elements/HexRule20.h b/MeshLib/Elements/HexRule20.h
index 5d1c442bc23..efc53b437e4 100644
--- a/MeshLib/Elements/HexRule20.h
+++ b/MeshLib/Elements/HexRule20.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef HEXRULE20_H_
-#define HEXRULE20_H_
+#pragma once
 
 #include "MeshLib/MeshEnums.h"
 #include "Element.h"
@@ -67,6 +66,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* HEXRULE20_H_ */
-
diff --git a/MeshLib/Elements/HexRule8.h b/MeshLib/Elements/HexRule8.h
index 7d931592791..b1de7ac5556 100644
--- a/MeshLib/Elements/HexRule8.h
+++ b/MeshLib/Elements/HexRule8.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef HEXRULE8_H_
-#define HEXRULE8_H_
+#pragma once
 
 #include "MeshLib/MeshEnums.h"
 #include "Element.h"
@@ -100,6 +99,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* HEXRULE_H_ */
-
diff --git a/MeshLib/Elements/Line.h b/MeshLib/Elements/Line.h
index 221fc90c2f7..c4ef9440fa2 100644
--- a/MeshLib/Elements/Line.h
+++ b/MeshLib/Elements/Line.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef LINE_H_
-#define LINE_H_
+#pragma once
 
 #include "TemplateElement.h"
 #include "LineRule2.h"
@@ -28,6 +27,3 @@ typedef TemplateElement<LineRule2> Line;
 typedef TemplateElement<LineRule3> Line3;
 
 }
-
-
-#endif /* LINE_H_ */
diff --git a/MeshLib/Elements/LineRule2.h b/MeshLib/Elements/LineRule2.h
index 89f63f979b8..52b6b494ede 100644
--- a/MeshLib/Elements/LineRule2.h
+++ b/MeshLib/Elements/LineRule2.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef LINERULE2_H_
-#define LINERULE2_H_
+#pragma once
 
 #include "MeshLib/MeshEnums.h"
 #include "Element.h"
@@ -69,6 +68,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* LINERULE2_H_ */
-
diff --git a/MeshLib/Elements/LineRule3.h b/MeshLib/Elements/LineRule3.h
index 2d5b52786dd..8489a8167fa 100644
--- a/MeshLib/Elements/LineRule3.h
+++ b/MeshLib/Elements/LineRule3.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef LINERULE3_H_
-#define LINERULE3_H_
+#pragma once
 
 #include "MeshLib/MeshEnums.h"
 #include "LineRule2.h"
@@ -36,6 +35,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* LINERULE3_H_ */
-
diff --git a/MeshLib/Elements/Point.h b/MeshLib/Elements/Point.h
index 0c14fb588ee..953aaa5fc59 100644
--- a/MeshLib/Elements/Point.h
+++ b/MeshLib/Elements/Point.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MESHLIB_POINT_H_
-#define MESHLIB_POINT_H_
+#pragma once
 
 #include "TemplateElement.h"
 #include "PointRule1.h"
@@ -19,5 +18,3 @@ namespace MeshLib
 {
     using Point = TemplateElement<PointRule1>;
 }
-
-#endif  // MESHLIB_POINT_H_
diff --git a/MeshLib/Elements/PointRule1.h b/MeshLib/Elements/PointRule1.h
index 775420795b7..59f89ec3e27 100644
--- a/MeshLib/Elements/PointRule1.h
+++ b/MeshLib/Elements/PointRule1.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MESHLIB_POINTRULE1_H_
-#define MESHLIB_POINTRULE1_H_
+#pragma once
 
 #include "MeshLib/MeshEnums.h"
 #include "Element.h"
@@ -62,6 +61,3 @@ public:
     static double computeVolume(Node const* const* _nodes);
 };
 }
-
-#endif  // MESHLIB_POINTRULE1_H_
-
diff --git a/MeshLib/Elements/Prism.h b/MeshLib/Elements/Prism.h
index 68461b17a27..7176cfd7997 100644
--- a/MeshLib/Elements/Prism.h
+++ b/MeshLib/Elements/Prism.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef PRISM_H_
-#define PRISM_H_
+#pragma once
 
 #include "TemplateElement.h"
 #include "PrismRule6.h"
@@ -28,5 +27,3 @@ typedef TemplateElement<PrismRule6> Prism;
 typedef TemplateElement<PrismRule15> Prism15;
 
 }
-
-#endif /* PRISM_H_ */
diff --git a/MeshLib/Elements/PrismRule15.h b/MeshLib/Elements/PrismRule15.h
index 1fac76aee56..4f6bb721b12 100644
--- a/MeshLib/Elements/PrismRule15.h
+++ b/MeshLib/Elements/PrismRule15.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PRISMRULE15_H_
-#define PRISMRULE15_H_
+#pragma once
 
 #include "MeshLib/MeshEnums.h"
 #include "Element.h"
@@ -68,6 +67,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* PRISMRULE15_H_ */
-
diff --git a/MeshLib/Elements/PrismRule6.h b/MeshLib/Elements/PrismRule6.h
index 93472f614f3..aecd28b2159 100644
--- a/MeshLib/Elements/PrismRule6.h
+++ b/MeshLib/Elements/PrismRule6.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PRISMRULE6_H_
-#define PRISMRULE6_H_
+#pragma once
 
 #include "MeshLib/MeshEnums.h"
 #include "Element.h"
@@ -101,6 +100,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* PRISMRULE6_H_ */
-
diff --git a/MeshLib/Elements/Pyramid.h b/MeshLib/Elements/Pyramid.h
index 67bba3c0073..3ae5204c4cc 100644
--- a/MeshLib/Elements/Pyramid.h
+++ b/MeshLib/Elements/Pyramid.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef PYRAMID_H_
-#define PYRAMID_H_
+#pragma once
 
 #include "TemplateElement.h"
 #include "PyramidRule5.h"
@@ -28,5 +27,3 @@ typedef TemplateElement<PyramidRule5> Pyramid;
 typedef TemplateElement<PyramidRule13> Pyramid13;
 
 }
-
-#endif /* PYRAMID_H_ */
diff --git a/MeshLib/Elements/PyramidRule13.h b/MeshLib/Elements/PyramidRule13.h
index 0baa3e8ea03..987a6fc17e7 100644
--- a/MeshLib/Elements/PyramidRule13.h
+++ b/MeshLib/Elements/PyramidRule13.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PYRAMIDRULE13_H_
-#define PYRAMIDRULE13_H_
+#pragma once
 
 #include "MeshLib/MeshEnums.h"
 #include "Element.h"
@@ -67,6 +66,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* PYRAMIDRULE13_H_ */
-
diff --git a/MeshLib/Elements/PyramidRule5.h b/MeshLib/Elements/PyramidRule5.h
index 8c8a9b6c639..f1864743898 100644
--- a/MeshLib/Elements/PyramidRule5.h
+++ b/MeshLib/Elements/PyramidRule5.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PYRAMIDRULE5_H_
-#define PYRAMIDRULE5_H_
+#pragma once
 
 #include "MeshLib/MeshEnums.h"
 #include "Element.h"
@@ -100,6 +99,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* PYRAMIDRULE5_H_ */
-
diff --git a/MeshLib/Elements/Quad.h b/MeshLib/Elements/Quad.h
index f4b4730748e..ad1cd724d03 100644
--- a/MeshLib/Elements/Quad.h
+++ b/MeshLib/Elements/Quad.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef QUAD_H_
-#define QUAD_H_
+#pragma once
 
 #include "TemplateElement.h"
 #include "QuadRule4.h"
@@ -32,5 +31,3 @@ typedef TemplateElement<QuadRule8> Quad8;
 typedef TemplateElement<QuadRule9> Quad9;
 
 }
-
-#endif /* QUAD_H_ */
diff --git a/MeshLib/Elements/QuadRule4.h b/MeshLib/Elements/QuadRule4.h
index 5f1409f482c..31af81dfe9c 100644
--- a/MeshLib/Elements/QuadRule4.h
+++ b/MeshLib/Elements/QuadRule4.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef QUADRULE4_H_
-#define QUADRULE4_H_
+#pragma once
 
 #include "MeshLib/MeshEnums.h"
 #include "Element.h"
@@ -82,6 +81,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* QUADRULE4_H_ */
-
diff --git a/MeshLib/Elements/QuadRule8.h b/MeshLib/Elements/QuadRule8.h
index f83290ab523..e29b2d2fb6a 100644
--- a/MeshLib/Elements/QuadRule8.h
+++ b/MeshLib/Elements/QuadRule8.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef QUADRULE8_H_
-#define QUADRULE8_H_
+#pragma once
 
 #include "MeshLib/MeshEnums.h"
 #include "QuadRule4.h"
@@ -51,6 +50,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* QUADRULE8_H_ */
-
diff --git a/MeshLib/Elements/QuadRule9.h b/MeshLib/Elements/QuadRule9.h
index 47894bcff18..af33b4ba281 100644
--- a/MeshLib/Elements/QuadRule9.h
+++ b/MeshLib/Elements/QuadRule9.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef QUADRULE9_H_
-#define QUADRULE9_H_
+#pragma once
 
 #include "MeshLib/MeshEnums.h"
 #include "QuadRule8.h"
@@ -43,6 +42,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* QUADRULE9_H_ */
-
diff --git a/MeshLib/Elements/TemplateElement.h b/MeshLib/Elements/TemplateElement.h
index 39e36b03bdd..1a69946aa18 100644
--- a/MeshLib/Elements/TemplateElement.h
+++ b/MeshLib/Elements/TemplateElement.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TEMPLATEELEMENT_H_
-#define TEMPLATEELEMENT_H_
+#pragma once
 
 #include <array>
 #include <limits>
@@ -158,6 +157,3 @@ public:
 } // MeshLib
 
 #include "TemplateElement-impl.h"
-
-#endif /* TEMPLATEELEMENT_H_ */
-
diff --git a/MeshLib/Elements/Tet.h b/MeshLib/Elements/Tet.h
index 297a09ea0c0..ba4546c281e 100644
--- a/MeshLib/Elements/Tet.h
+++ b/MeshLib/Elements/Tet.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef TET_H_
-#define TET_H_
+#pragma once
 
 #include "TemplateElement.h"
 #include "TetRule4.h"
@@ -28,5 +27,3 @@ typedef TemplateElement<TetRule4> Tet;
 typedef TemplateElement<TetRule10> Tet10;
 
 }
-
-#endif /* TET_H_ */
diff --git a/MeshLib/Elements/TetRule10.h b/MeshLib/Elements/TetRule10.h
index fd627bf061c..cbb57b58a72 100644
--- a/MeshLib/Elements/TetRule10.h
+++ b/MeshLib/Elements/TetRule10.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TETRULE10_H_
-#define TETRULE10_H_
+#pragma once
 
 #include "MeshLib/MeshEnums.h"
 #include "Element.h"
@@ -62,6 +61,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* TETRULE10_H_ */
-
diff --git a/MeshLib/Elements/TetRule4.h b/MeshLib/Elements/TetRule4.h
index 1f7eb407d2a..745b9326b54 100644
--- a/MeshLib/Elements/TetRule4.h
+++ b/MeshLib/Elements/TetRule4.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TETRULE4_H_
-#define TETRULE4_H_
+#pragma once
 
 #include "MeshLib/MeshEnums.h"
 #include "Element.h"
@@ -95,6 +94,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* TETRULE4_H_ */
-
diff --git a/MeshLib/Elements/Tri.h b/MeshLib/Elements/Tri.h
index 2b5fbfe8544..ab67c611084 100644
--- a/MeshLib/Elements/Tri.h
+++ b/MeshLib/Elements/Tri.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef TRI_H_
-#define TRI_H_
+#pragma once
 
 #include "TemplateElement.h"
 #include "TriRule3.h"
@@ -29,5 +28,3 @@ typedef TemplateElement<TriRule3> Tri;
 typedef TemplateElement<TriRule6> Tri6;
 
 }
-
-#endif /* TRI_H_ */
diff --git a/MeshLib/Elements/TriRule3.h b/MeshLib/Elements/TriRule3.h
index 6a060081e77..f7f3c14c6c2 100644
--- a/MeshLib/Elements/TriRule3.h
+++ b/MeshLib/Elements/TriRule3.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TRIRULE3_H_
-#define TRIRULE3_H_
+#pragma once
 
 #include "MeshLib/MeshEnums.h"
 #include "Element.h"
@@ -83,6 +82,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* TRIRULE3_H_ */
-
diff --git a/MeshLib/Elements/TriRule6.h b/MeshLib/Elements/TriRule6.h
index ec12465bd3c..d2b234cd0d2 100644
--- a/MeshLib/Elements/TriRule6.h
+++ b/MeshLib/Elements/TriRule6.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TRIRULE6_H_
-#define TRIRULE6_H_
+#pragma once
 
 #include "MeshLib/MeshEnums.h"
 #include "TriRule3.h"
@@ -54,6 +53,3 @@ public:
 }; /* class */
 
 } /* namespace */
-
-#endif /* TRIRULE6_H_ */
-
diff --git a/MeshLib/Elements/Utils.h b/MeshLib/Elements/Utils.h
index ee56bee41f1..c355142a40a 100644
--- a/MeshLib/Elements/Utils.h
+++ b/MeshLib/Elements/Utils.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MESHLIB_ELEMENTS_UTILS_H_
-#define MESHLIB_ELEMENTS_UTILS_H_
+#pragma once
 
 #include <algorithm>
 #include <vector>
@@ -41,5 +40,3 @@ inline std::vector<Node*> getBaseNodes(std::vector<Element*> const& elements)
 }
 
 }  // namespace MeshLib
-
-#endif  // MESHLIB_ELEMENTS_UTILS_H_
diff --git a/MeshLib/Elements/VertexRule.h b/MeshLib/Elements/VertexRule.h
index 09b809cfcf5..2651a448043 100644
--- a/MeshLib/Elements/VertexRule.h
+++ b/MeshLib/Elements/VertexRule.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MESHLIB_VERTEX_RULE_H
-#define MESHLIB_VERTEX_RULE_H
+#pragma once
 
 namespace MeshLib
 {
@@ -40,6 +39,3 @@ public:
 };
 
 }
-
-#endif // MESHLIB_VERTEX_RULE_H
-
diff --git a/MeshLib/IO/Legacy/MeshIO.h b/MeshLib/IO/Legacy/MeshIO.h
index 51c5152ecb3..dca1fae9a54 100644
--- a/MeshLib/IO/Legacy/MeshIO.h
+++ b/MeshLib/IO/Legacy/MeshIO.h
@@ -12,9 +12,7 @@
  *
  */
 
-
-#ifndef MESHIO_H_
-#define MESHIO_H_
+#pragma once
 
 #include <string>
 #include <vector>
@@ -68,5 +66,3 @@ private:
 } // end namespace Legacy
 } // end namespace IO
 } // end namespace MeshLib
-
-#endif /* MESHIO_H_ */
diff --git a/MeshLib/IO/MPI_IO/NodePartitionedMeshReader.h b/MeshLib/IO/MPI_IO/NodePartitionedMeshReader.h
index f9ccf81ec99..cf302e0fd76 100644
--- a/MeshLib/IO/MPI_IO/NodePartitionedMeshReader.h
+++ b/MeshLib/IO/MPI_IO/NodePartitionedMeshReader.h
@@ -11,8 +11,7 @@
                http://www.opengeosys.org/project/license
  */
 
-#ifndef NODE_PARTITIONED_MESH_READER_H
-#define NODE_PARTITIONED_MESH_READER_H
+#pragma once
 
 #include <iosfwd>
 #include <string>
@@ -252,5 +251,3 @@ private:
 };
 }   // end namespace IO
 }   // end namespace MeshLib
-
-#endif  // READ_NODE_PARTITIONED_MESH_H
diff --git a/MeshLib/IO/VtkIO/PVDFile.h b/MeshLib/IO/VtkIO/PVDFile.h
index 237a17eed1f..1e7e30ea278 100644
--- a/MeshLib/IO/VtkIO/PVDFile.h
+++ b/MeshLib/IO/VtkIO/PVDFile.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MESHLIB_VTKIO_PVDFILE_H
-#define MESHLIB_VTKIO_PVDFILE_H
+#pragma once
 
 #include <string>
 #include <vector>
@@ -37,5 +36,3 @@ private:
 
 } // namespace IO
 } // namespace MeshLib
-
-#endif // MESHLIB_VTKIO_PVDFILE_H
diff --git a/MeshLib/IO/VtkIO/VtuInterface.h b/MeshLib/IO/VtkIO/VtuInterface.h
index 0dcf69b00b0..b7463b4c0f4 100644
--- a/MeshLib/IO/VtkIO/VtuInterface.h
+++ b/MeshLib/IO/VtkIO/VtuInterface.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef VTUINTERFACE_H_
-#define VTUINTERFACE_H_
+#pragma once
 
 #include <string>
 #include <vtkXMLWriter.h>
@@ -59,5 +58,3 @@ private:
 } // end namespace MeshLib
 
 #include "VtuInterface-impl.h"
-
-#endif /* VTUINTERFACE_H_ */
diff --git a/MeshLib/IO/readMeshFromFile.h b/MeshLib/IO/readMeshFromFile.h
index def517e741b..8b2ce3d0935 100644
--- a/MeshLib/IO/readMeshFromFile.h
+++ b/MeshLib/IO/readMeshFromFile.h
@@ -16,8 +16,7 @@
  * @author Karsten Rink
  */
 
-#ifndef READMESHFROMFILE_H
-#define READMESHFROMFILE_H
+#pragma once
 
 #include <string>
 
@@ -31,4 +30,3 @@ MeshLib::Mesh* readMeshFromFileSerial(const std::string &file_name);
 MeshLib::Mesh* readMeshFromFile(const std::string &file_name);
 }
 }
-#endif // READMESHFROMFILE_H
diff --git a/MeshLib/IO/writeMeshToFile.h b/MeshLib/IO/writeMeshToFile.h
index 4569a0aa625..bd91dd447d5 100644
--- a/MeshLib/IO/writeMeshToFile.h
+++ b/MeshLib/IO/writeMeshToFile.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef WRITEMESHTOFILE_H_
-#define WRITEMESHTOFILE_H_
+#pragma once
 
 #include <string>
 
@@ -19,5 +18,3 @@ namespace IO
 int writeMeshToFile(const MeshLib::Mesh &mesh, const std::string &file_name);
 }
 }
-
-#endif // WRITEMESHTOFILE_H_
diff --git a/MeshLib/Location.h b/MeshLib/Location.h
index 75a39b48382..64ddc761c04 100644
--- a/MeshLib/Location.h
+++ b/MeshLib/Location.h
@@ -13,8 +13,7 @@
 #include <cstddef>
 #include <iosfwd>
 
-#ifndef LOCATION_H_
-#define LOCATION_H_
+#pragma once
 
 namespace MeshLib
 {
@@ -50,5 +49,3 @@ bool operator<(const Location& left, const Location& right)
 std::ostream& operator<<(std::ostream& os, Location const& l);
 
 }   // namespace MeshLib
-
-#endif  // LOCATION_H_
diff --git a/MeshLib/Mesh.h b/MeshLib/Mesh.h
index 4df518524a4..9809e73e7b4 100644
--- a/MeshLib/Mesh.h
+++ b/MeshLib/Mesh.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MESH_H_
-#define MESH_H_
+#pragma once
 
 #include <cstdlib>
 #include <string>
@@ -236,6 +235,3 @@ void addPropertyToMesh(MeshLib::Mesh& mesh, std::string const& name,
 }
 
 } /* namespace */
-
-#endif /* MESH_H_ */
-
diff --git a/MeshLib/MeshEditing/AddLayerToMesh.h b/MeshLib/MeshEditing/AddLayerToMesh.h
index 07f9b522c0e..6c71c16ca32 100644
--- a/MeshLib/MeshEditing/AddLayerToMesh.h
+++ b/MeshLib/MeshEditing/AddLayerToMesh.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef ADDLAYERTOMESH_H
-#define ADDLAYERTOMESH_H
+#pragma once
 
 #include <vector>
 #include <string>
@@ -43,5 +42,3 @@ MeshLib::Mesh* addLayerToMesh(MeshLib::Mesh const& mesh,
     bool on_top);
 
 } // end namespace MeshLib
-
-#endif //ADDLAYERTOMESH_H
diff --git a/MeshLib/MeshEditing/ConvertToLinearMesh.h b/MeshLib/MeshEditing/ConvertToLinearMesh.h
index 33462b62d76..40f541b64d7 100644
--- a/MeshLib/MeshEditing/ConvertToLinearMesh.h
+++ b/MeshLib/MeshEditing/ConvertToLinearMesh.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MESHLIB_CONVERRTTOLINEARMESH_H_
-#define MESHLIB_CONVERRTTOLINEARMESH_H_
+#pragma once
 
 #include <memory>
 #include <string>
@@ -24,5 +23,3 @@ std::unique_ptr<MeshLib::Mesh> convertToLinearMesh(
     const MeshLib::Mesh& mesh, const std::string& new_mesh_name);
 
 } // end namespace MeshLib
-
-#endif //MESHLIB_CONVERRTTOLINEARMESH_H_
diff --git a/MeshLib/MeshEditing/DuplicateMeshComponents.h b/MeshLib/MeshEditing/DuplicateMeshComponents.h
index 9b506d14334..a0156791291 100644
--- a/MeshLib/MeshEditing/DuplicateMeshComponents.h
+++ b/MeshLib/MeshEditing/DuplicateMeshComponents.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef DUPLICATEMESHCOMPONENTS_H
-#define DUPLICATEMESHCOMPONENTS_H
+#pragma once
 
 #include <vector>
 
@@ -43,5 +42,3 @@ namespace MeshLib
     MeshLib::Element* copyElement(MeshLib::Element const*const element, const std::vector<MeshLib::Node*> &nodes);
 
 } // end namespace MeshLib
-
-#endif //DUPLICATEMESHCOMPONENTS_H
diff --git a/MeshLib/MeshEditing/ElementValueModification.h b/MeshLib/MeshEditing/ElementValueModification.h
index f9055412e74..8fa50b017b8 100644
--- a/MeshLib/MeshEditing/ElementValueModification.h
+++ b/MeshLib/MeshEditing/ElementValueModification.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MESHVALUEMODIFICATION_H
-#define MESHVALUEMODIFICATION_H
+#pragma once
 
 #include <vector>
 
@@ -77,5 +76,3 @@ private:
 };
 
 } // end namespace MeshLib
-
-#endif //MESHVALUEMODIFICATION_H
diff --git a/MeshLib/MeshEditing/FlipElements.h b/MeshLib/MeshEditing/FlipElements.h
index 365b29f208e..94b587619f2 100644
--- a/MeshLib/MeshEditing/FlipElements.h
+++ b/MeshLib/MeshEditing/FlipElements.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef FLIPELEMENTS_H_
-#define FLIPELEMENTS_H_
+#pragma once
 
 #include <memory>
 #include <vector>
@@ -39,5 +38,3 @@ std::unique_ptr<MeshLib::Element> createFlippedElement(MeshLib::Element const& e
 std::unique_ptr<MeshLib::Mesh> createFlippedMesh(MeshLib::Mesh const& mesh);
 
 }
-
-#endif //FLIPELEMENTS_H_
diff --git a/MeshLib/MeshEditing/Mesh2MeshPropertyInterpolation.h b/MeshLib/MeshEditing/Mesh2MeshPropertyInterpolation.h
index 4b6bf548141..19d9be31016 100644
--- a/MeshLib/MeshEditing/Mesh2MeshPropertyInterpolation.h
+++ b/MeshLib/MeshEditing/Mesh2MeshPropertyInterpolation.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MESH2MESHPROPERTYINTERPOLATION_H_
-#define MESH2MESHPROPERTYINTERPOLATION_H_
+#pragma once
 
 #include "MeshLib/PropertyVector.h"
 
@@ -70,5 +69,3 @@ private:
 };
 
 } // end namespace MeshLib
-
-#endif /* MESH2MESHPROPERTYINTERPOLATION_H_ */
diff --git a/MeshLib/MeshEditing/MeshRevision.h b/MeshLib/MeshEditing/MeshRevision.h
index 1545f5faa8a..6eb0c294b5e 100644
--- a/MeshLib/MeshEditing/MeshRevision.h
+++ b/MeshLib/MeshEditing/MeshRevision.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MESHREVISION_H_
-#define MESHREVISION_H_
+#pragma once
 
 #include <array>
 #include <limits>
@@ -192,5 +191,3 @@ private:
 };
 
 }
-
-#endif /* MESHREVISION_H_ */
diff --git a/MeshLib/MeshEditing/RemoveMeshComponents.h b/MeshLib/MeshEditing/RemoveMeshComponents.h
index 8ac0f182a2e..6ed2af75f39 100644
--- a/MeshLib/MeshEditing/RemoveMeshComponents.h
+++ b/MeshLib/MeshEditing/RemoveMeshComponents.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef REMOVEMESHCOMPONENTS_H_
-#define REMOVEMESHCOMPONENTS_H_
+#pragma once
 
 #include <string>
 #include <vector>
@@ -38,5 +37,3 @@ MeshLib::Mesh* removeElements(const MeshLib::Mesh& mesh,
 MeshLib::Mesh* removeNodes(const MeshLib::Mesh &mesh, const std::vector<std::size_t> &removed_node_ids, const std::string &new_mesh_name);
 
 } // end namespace MeshLib
-
-#endif //REMOVEMESHCOMPONENTS_H_
diff --git a/MeshLib/MeshEditing/moveMeshNodes.h b/MeshLib/MeshEditing/moveMeshNodes.h
index ce44720e1b6..27ef1fc4cdc 100644
--- a/MeshLib/MeshEditing/moveMeshNodes.h
+++ b/MeshLib/MeshEditing/moveMeshNodes.h
@@ -10,8 +10,7 @@
  *              See accompanying file LICENSE.txt or
  *              http://www.opengeosys.org/project/license
  */
-#ifndef MOVEMESHNODES_H_
-#define MOVEMESHNODES_H_
+#pragma once
 
 #include "MeshLib/Node.h"
 
@@ -44,5 +43,3 @@ void moveMeshNodes(
 };
 
 } // end namespace MeshLib
-
-#endif /* MOVEMESHNODES_H_ */
diff --git a/MeshLib/MeshEditing/projectMeshOntoPlane.h b/MeshLib/MeshEditing/projectMeshOntoPlane.h
index eff6010fa2c..a67eb231384 100644
--- a/MeshLib/MeshEditing/projectMeshOntoPlane.h
+++ b/MeshLib/MeshEditing/projectMeshOntoPlane.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef PROJECTMESHONTOPLANE_H
-#define PROJECTMESHONTOPLANE_H
+#pragma once
 
 #include <vector>
 
@@ -57,5 +56,3 @@ MeshLib::Mesh* projectMeshOntoPlane(MeshLib::Mesh const& mesh,
 }
 
 } // end namespace MeshLib
-
-#endif //PROJECTMESHONTOPLANE_H
diff --git a/MeshLib/MeshEnums.h b/MeshLib/MeshEnums.h
index 7b75b5562f5..5a24cf9a24a 100644
--- a/MeshLib/MeshEnums.h
+++ b/MeshLib/MeshEnums.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MESHENUMS_H
-#define MESHENUMS_H
+#pragma once
 
 #include <string>
 #include <vector>
@@ -108,5 +107,3 @@ const std::string CellType2String(const CellType t);
 const std::string MeshQualityType2String(const MeshQualityType t);
 
 }
-
-#endif //MESHENUMS_H
diff --git a/MeshLib/MeshGenerators/LayeredMeshGenerator.h b/MeshLib/MeshGenerators/LayeredMeshGenerator.h
index 02382618399..17cb36910fe 100644
--- a/MeshLib/MeshGenerators/LayeredMeshGenerator.h
+++ b/MeshLib/MeshGenerators/LayeredMeshGenerator.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef LAYEREDMESHGENERATOR_H
-#define LAYEREDMESHGENERATOR_H
+#pragma once
 
 #include <memory>
 #include <limits>
@@ -99,5 +98,3 @@ protected:
     std::vector<MeshLib::Node*> _nodes;
     std::vector<MeshLib::Element*> _elements;
 };
-
-#endif //LAYEREDMESHGENERATOR_H
diff --git a/MeshLib/MeshGenerators/LayeredVolume.h b/MeshLib/MeshGenerators/LayeredVolume.h
index 7816784955c..a96a1a64019 100644
--- a/MeshLib/MeshGenerators/LayeredVolume.h
+++ b/MeshLib/MeshGenerators/LayeredVolume.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef LAYEREDVOLUME_H
-#define LAYEREDVOLUME_H
+#pragma once
 
 #include <string>
 #include <vector>
@@ -63,5 +62,3 @@ private:
 
     std::vector<MeshLib::Node> _attribute_points;
 };
-
-#endif //LAYEREDVOLUME_H
diff --git a/MeshLib/MeshGenerators/MeshGenerator.h b/MeshLib/MeshGenerators/MeshGenerator.h
index 919fede8019..4ae5725e419 100644
--- a/MeshLib/MeshGenerators/MeshGenerator.h
+++ b/MeshLib/MeshGenerators/MeshGenerator.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MESHGENERATOR_H_
-#define MESHGENERATOR_H_
+#pragma once
 
 #include <array>
 #include <functional>
@@ -508,5 +507,3 @@ createSurfaceMesh(std::string const& mesh_name,
 
 }  //MeshGenerator
 } //MeshLib
-
-#endif //MESHGENERATOR_H_
diff --git a/MeshLib/MeshGenerators/MeshLayerMapper.h b/MeshLib/MeshGenerators/MeshLayerMapper.h
index 5a5428c9d1b..382826b405e 100644
--- a/MeshLib/MeshGenerators/MeshLayerMapper.h
+++ b/MeshLib/MeshGenerators/MeshLayerMapper.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MESHLAYERMAPPER_H
-#define MESHLAYERMAPPER_H
+#pragma once
 
 #include "LayeredMeshGenerator.h"
 
@@ -71,5 +70,3 @@ private:
 };
 
 } // end namespace MeshLib
-
-#endif //MESHLAYERMAPPER_H
diff --git a/MeshLib/MeshGenerators/RasterToMesh.h b/MeshLib/MeshGenerators/RasterToMesh.h
index 4c1efde0053..e386f969416 100644
--- a/MeshLib/MeshGenerators/RasterToMesh.h
+++ b/MeshLib/MeshGenerators/RasterToMesh.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef RASTERTOMESH_H
-#define RASTERTOMESH_H
+#pragma once
 
 #include <logog/include/logog.hpp>
 
@@ -134,5 +133,3 @@ private:
 };
 
 } // end namespace MeshLib
-
-#endif // RASTERTOMESH_H
diff --git a/MeshLib/MeshGenerators/VtkMeshConverter.h b/MeshLib/MeshGenerators/VtkMeshConverter.h
index 2c15d32be38..704c28cb131 100644
--- a/MeshLib/MeshGenerators/VtkMeshConverter.h
+++ b/MeshLib/MeshGenerators/VtkMeshConverter.h
@@ -13,8 +13,7 @@
  *
  */
 
-#ifndef VTKMESHCONVERTER_H
-#define VTKMESHCONVERTER_H
+#pragma once
 
 #include <vtkDataArray.h>
 #include <vtkType.h>
@@ -119,5 +118,3 @@ private:
 };
 
 } // end namespace MeshLib
-
-#endif // VTKMESHCONVERTER_H
diff --git a/MeshLib/MeshInformation.h b/MeshLib/MeshInformation.h
index 52f3fe39a6b..867b4d9f2d5 100644
--- a/MeshLib/MeshInformation.h
+++ b/MeshLib/MeshInformation.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MESHINFORMATION_H
-#define MESHINFORMATION_H
+#pragma once
 
 #include <array>
 #include <string>
@@ -71,5 +70,3 @@ public:
 };
 
 }
-
-#endif //MESHINFORMATION_H
diff --git a/MeshLib/MeshQuality/AngleSkewMetric.h b/MeshLib/MeshQuality/AngleSkewMetric.h
index c76e093da9a..c7eee5a98e7 100644
--- a/MeshLib/MeshQuality/AngleSkewMetric.h
+++ b/MeshLib/MeshQuality/AngleSkewMetric.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef ANGLESKEWMETRIC_H_
-#define ANGLESKEWMETRIC_H_
+#pragma once
 
 #include "ElementQualityMetric.h"
 
@@ -45,5 +44,3 @@ private:
                                     double &min_angle, double &max_angle) const;
 };
 }
-
-#endif /* ANGLESKEWMETRIC_H_ */
diff --git a/MeshLib/MeshQuality/EdgeRatioMetric.h b/MeshLib/MeshQuality/EdgeRatioMetric.h
index 03c974eb230..f7198e88d92 100644
--- a/MeshLib/MeshQuality/EdgeRatioMetric.h
+++ b/MeshLib/MeshQuality/EdgeRatioMetric.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef EDGERATIOMETRIC_H_
-#define EDGERATIOMETRIC_H_
+#pragma once
 
 #include "ElementQualityMetric.h"
 #include "MathLib/Point3d.h"
@@ -49,5 +48,3 @@ private:
     double checkHexahedron (std::vector<const MathLib::Point3d*> const& pnts) const;
 };
 }
-
-#endif /* EDGERATIOMETRIC_H_ */
diff --git a/MeshLib/MeshQuality/ElementQualityInterface.h b/MeshLib/MeshQuality/ElementQualityInterface.h
index 18b1c9a20f5..0594c41d7da 100644
--- a/MeshLib/MeshQuality/ElementQualityInterface.h
+++ b/MeshLib/MeshQuality/ElementQualityInterface.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef ELEMENTQUALITYINTERFACE_H_
-#define ELEMENTQUALITYINTERFACE_H_
+#pragma once
 
 #include <vector>
 
@@ -109,5 +108,3 @@ private:
 };
 
 }
-
-#endif /* ELEMENTQUALITYINTERFACE_H_ */
diff --git a/MeshLib/MeshQuality/ElementQualityMetric.h b/MeshLib/MeshQuality/ElementQualityMetric.h
index c0a4c0fd1de..3cc2607c541 100644
--- a/MeshLib/MeshQuality/ElementQualityMetric.h
+++ b/MeshLib/MeshQuality/ElementQualityMetric.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef ELEMENTQUALITYMETRIC_H_
-#define ELEMENTQUALITYMETRIC_H_
+#pragma once
 
 #include <vector>
 
@@ -62,5 +61,3 @@ protected:
     std::vector<double> _element_quality_metric;
 };
 }
-
-#endif /* ELEMENTQUALITYMETRIC_H_ */
diff --git a/MeshLib/MeshQuality/ElementSizeMetric.h b/MeshLib/MeshQuality/ElementSizeMetric.h
index 6f4a1ffec4c..f7aa062f54c 100644
--- a/MeshLib/MeshQuality/ElementSizeMetric.h
+++ b/MeshLib/MeshQuality/ElementSizeMetric.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef ELEMENTSIZEMETRIC_H_
-#define ELEMENTSIZEMETRIC_H_
+#pragma once
 
 #include "ElementQualityMetric.h"
 
@@ -37,5 +36,3 @@ private:
     std::size_t calc3dQuality();
 };
 }
-
-#endif /* ELEMENTSIZEMETRIC_H_ */
diff --git a/MeshLib/MeshQuality/MeshValidation.h b/MeshLib/MeshQuality/MeshValidation.h
index ab4d62b0298..391c226a2f5 100644
--- a/MeshLib/MeshQuality/MeshValidation.h
+++ b/MeshLib/MeshQuality/MeshValidation.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MESHVALIDATION_H
-#define MESHVALIDATION_H
+#pragma once
 
 #include <array>
 #include <vector>
@@ -77,5 +76,3 @@ private:
 };
 
 } // end namespace MeshLib
-
-#endif //MESHVALIDATION_H
diff --git a/MeshLib/MeshQuality/RadiusEdgeRatioMetric.h b/MeshLib/MeshQuality/RadiusEdgeRatioMetric.h
index 8add8f07c31..da9fc775685 100644
--- a/MeshLib/MeshQuality/RadiusEdgeRatioMetric.h
+++ b/MeshLib/MeshQuality/RadiusEdgeRatioMetric.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef RADIUSEDGERATIOMETRIC_H_
-#define RADIUSEDGERATIOMETRIC_H_
+#pragma once
 
 #include "ElementQualityMetric.h"
 
@@ -33,5 +32,3 @@ public:
     virtual void calculateQuality ();
 };
 }
-
-#endif /* RADIUSEDGERATIOMETRIC_H_ */
diff --git a/MeshLib/MeshQuality/SizeDifferenceMetric.h b/MeshLib/MeshQuality/SizeDifferenceMetric.h
index 1c4d77e4004..399fd2385b5 100644
--- a/MeshLib/MeshQuality/SizeDifferenceMetric.h
+++ b/MeshLib/MeshQuality/SizeDifferenceMetric.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef SIZEDIFFERENCEMETRIC_H_
-#define SIZEDIFFERENCEMETRIC_H_
+#pragma once
 
 #include "ElementQualityMetric.h"
 
@@ -33,5 +32,3 @@ public:
     virtual void calculateQuality ();
 };
 }
-
-#endif /* SIZEDIFFERENCEMETRIC_H_ */
diff --git a/MeshLib/MeshSearch/ElementSearch.h b/MeshLib/MeshSearch/ElementSearch.h
index 881cfa63f31..80b48055953 100644
--- a/MeshLib/MeshSearch/ElementSearch.h
+++ b/MeshLib/MeshSearch/ElementSearch.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef ELEMENTSEARCH_H_
-#define ELEMENTSEARCH_H_
+#pragma once
 
 #include <limits>
 #include <vector>
@@ -97,5 +96,3 @@ private:
 };
 
 } // end namespace MeshLib
-
-#endif //ELEMENTEXTRACTION_H
diff --git a/MeshLib/MeshSearch/MeshElementGrid.h b/MeshLib/MeshSearch/MeshElementGrid.h
index 4399bd865c7..18e718e021d 100644
--- a/MeshLib/MeshSearch/MeshElementGrid.h
+++ b/MeshLib/MeshSearch/MeshElementGrid.h
@@ -8,8 +8,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef MESHELEMENTGRID_H_
-#define MESHELEMENTGRID_H_
+#pragma once
 
 #include <array>
 #include <limits>
@@ -105,5 +104,3 @@ void getGridGeometry(MeshLib::MeshElementGrid const& grid,
 #endif
 
 } // end namespace MeshLib
-
-#endif /* MESHELEMENTGRID_H_ */
diff --git a/MeshLib/MeshSearch/NodeSearch.h b/MeshLib/MeshSearch/NodeSearch.h
index 0523596b7d9..1a9cdb36cdd 100644
--- a/MeshLib/MeshSearch/NodeSearch.h
+++ b/MeshLib/MeshSearch/NodeSearch.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NODESEARCH_H_
-#define NODESEARCH_H_
+#pragma once
 
 #include <vector>
 
@@ -53,5 +52,3 @@ private:
 std::vector<Node*> getUniqueNodes(std::vector<Element*> const& elements);
 
 } // end namespace MeshLib
-
-#endif //NODESEARCH_H_
diff --git a/MeshLib/MeshSubset.h b/MeshLib/MeshSubset.h
index e8f83ba5359..b10bae59627 100644
--- a/MeshLib/MeshSubset.h
+++ b/MeshLib/MeshSubset.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef MESHSUBSET_H_
-#define MESHSUBSET_H_
+#pragma once
 
 #include <cassert>
 #include <vector>
@@ -170,5 +169,3 @@ private:
 };
 
 }   // namespace MeshLib
-
-#endif  // MESHSUBSET_H_
diff --git a/MeshLib/MeshSubsets.h b/MeshLib/MeshSubsets.h
index 69ad967fc34..7e28bebdcba 100644
--- a/MeshLib/MeshSubsets.h
+++ b/MeshLib/MeshSubsets.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef MESHSUBSETS_H_
-#define MESHSUBSETS_H_
+#pragma once
 
 #include <algorithm>
 #include <cstdlib>
@@ -108,5 +107,3 @@ private:
 };
 
 }   // namespace MeshLib
-
-#endif    // MESHSUBSETS_H_
diff --git a/MeshLib/MeshSurfaceExtraction.h b/MeshLib/MeshSurfaceExtraction.h
index d1b04a75b42..c59d617e8ab 100644
--- a/MeshLib/MeshSurfaceExtraction.h
+++ b/MeshLib/MeshSurfaceExtraction.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef MESHSURFACEEXTRACTION_H
-#define MESHSURFACEEXTRACTION_H
+#pragma once
 
 #include <cstddef>
 #include <vector>
@@ -95,5 +94,3 @@ private:
 };
 
 } // end namespace MeshLib
-
-#endif //MESHSURFACEEXTRACTION_H
diff --git a/MeshLib/Node.h b/MeshLib/Node.h
index 215404b95d1..cc62d741ccd 100644
--- a/MeshLib/Node.h
+++ b/MeshLib/Node.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef NODE_H_
-#define NODE_H_
+#pragma once
 
 #include <cstdlib>
 #include <limits>
@@ -104,6 +103,3 @@ protected:
 }; /* class */
 
 } /* namespace */
-
-#endif /* NODE_H_ */
-
diff --git a/MeshLib/NodeAdjacencyTable.h b/MeshLib/NodeAdjacencyTable.h
index 249baacb71f..c72d4ca99ad 100644
--- a/MeshLib/NodeAdjacencyTable.h
+++ b/MeshLib/NodeAdjacencyTable.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef MESHLIB_NODE_ADJACENCE_TABLE_H_
-#define MESHLIB_NODE_ADJACENCE_TABLE_H_
+#pragma once
 
 #include <algorithm>
 #include <vector>
@@ -81,5 +80,3 @@ private:
 };
 
 }   // namespace MeshLib
-
-#endif  //MESHLIB_NODE_ADJACENCE_TABLE_H_
diff --git a/MeshLib/NodePartitionedMesh.h b/MeshLib/NodePartitionedMesh.h
index 2cc5fe16ef8..f858ad3ac63 100644
--- a/MeshLib/NodePartitionedMesh.h
+++ b/MeshLib/NodePartitionedMesh.h
@@ -13,8 +13,7 @@
 
 */
 
-#ifndef NODE_PARTITIONED_MESH_H_
-#define NODE_PARTITIONED_MESH_H_
+#pragma once
 
 #include <algorithm>
 #include <string>
@@ -175,5 +174,3 @@ class NodePartitionedMesh : public Mesh
 };
 
 }   // namespace MeshLib
-
-#endif // NODE_PARTITIONED_MESH_H_
diff --git a/MeshLib/Properties.h b/MeshLib/Properties.h
index 6d7d34606cb..fcb5bfd9da5 100644
--- a/MeshLib/Properties.h
+++ b/MeshLib/Properties.h
@@ -11,8 +11,7 @@
  *
  */
 
-#ifndef PROPERTIES_H_
-#define PROPERTIES_H_
+#pragma once
 
 #include <cstdlib>
 #include <string>
@@ -128,6 +127,3 @@ private:
 #include "Properties-impl.h"
 
 } // end namespace MeshLib
-
-#endif
-
diff --git a/MeshLib/PropertyVector.h b/MeshLib/PropertyVector.h
index a5baee16101..81177345474 100644
--- a/MeshLib/PropertyVector.h
+++ b/MeshLib/PropertyVector.h
@@ -8,8 +8,7 @@
  *
  */
 
-#ifndef PROPERTYVECTOR_H_
-#define PROPERTYVECTOR_H_
+#pragma once
 
 #include <cassert>
 #include <iterator>
@@ -272,5 +271,3 @@ private:
 };
 
 } // end namespace MeshLib
-
-#endif
diff --git a/MeshLib/Vtk/VtkMappedMesh.h b/MeshLib/Vtk/VtkMappedMesh.h
index 36e945640f5..bab5cfc07d5 100644
--- a/MeshLib/Vtk/VtkMappedMesh.h
+++ b/MeshLib/Vtk/VtkMappedMesh.h
@@ -14,8 +14,7 @@
  *
  */
 
-#ifndef VTKMAPPEDMESH_H_
-#define VTKMAPPEDMESH_H_
+#pragma once
 
 #include <vtkObject.h>
 #include <vtkMappedUnstructuredGrid.h>
@@ -73,5 +72,3 @@ private:
 vtkMakeMappedUnstructuredGrid(VtkMappedMesh, VtkMappedMeshImpl)
 
 } // end namespace
-
-#endif // VTKMAPPEDMESH_H_
diff --git a/MeshLib/Vtk/VtkMappedMeshSource.h b/MeshLib/Vtk/VtkMappedMeshSource.h
index c1c5540ceeb..4c84f937d9e 100644
--- a/MeshLib/Vtk/VtkMappedMeshSource.h
+++ b/MeshLib/Vtk/VtkMappedMeshSource.h
@@ -20,8 +20,7 @@
  *
  */
 
-#ifndef _VTKMAPPEDMESHSOURCE
-#define _VTKMAPPEDMESHSOURCE
+#pragma once
 
 #include <string>
 #include <vector>
@@ -113,5 +112,3 @@ private:
 };
 
 } // Namespace MeshLib
-
-#endif //_VTKMAPPEDMESHSOURCE
diff --git a/MeshLib/Vtk/VtkMappedPropertyVectorTemplate.h b/MeshLib/Vtk/VtkMappedPropertyVectorTemplate.h
index 4292af527a0..80b9436faef 100644
--- a/MeshLib/Vtk/VtkMappedPropertyVectorTemplate.h
+++ b/MeshLib/Vtk/VtkMappedPropertyVectorTemplate.h
@@ -13,8 +13,7 @@
  *
  */
 
-#ifndef VTKMAPPEDELEMENTDATAARRAY_H_
-#define VTKMAPPEDELEMENTDATAARRAY_H_
+#pragma once
 
 #include <vtkMappedDataArray.h>
 #include <vtkObjectFactory.h>  // for vtkStandardNewMacro
@@ -136,5 +135,3 @@ private:
 } // end namespace MeshLib
 
 #include "VtkMappedPropertyVectorTemplate-impl.h"
-
-#endif // VTKMAPPEDELEMENTDATAARRAY_H_
diff --git a/MeshLib/Vtk/VtkMeshNodalCoordinatesTemplate.h b/MeshLib/Vtk/VtkMeshNodalCoordinatesTemplate.h
index 7cbe8986ac1..350736b8f0b 100644
--- a/MeshLib/Vtk/VtkMeshNodalCoordinatesTemplate.h
+++ b/MeshLib/Vtk/VtkMeshNodalCoordinatesTemplate.h
@@ -13,8 +13,7 @@
  *
  */
 
-#ifndef VTKMESHNODALCOORDINATES_H_
-#define VTKMESHNODALCOORDINATES_H_
+#pragma once
 
 #include <vtkMappedDataArray.h>
 #include <vtkObjectFactory.h>  // for vtkStandardNewMacro
@@ -134,5 +133,3 @@ private:
 } // end namespace
 
 #include "VtkMeshNodalCoordinatesTemplate-impl.h"
-
-#endif // VTKMESHNODALCOORDINATES_H_
diff --git a/MeshLib/VtkOGSEnum.h b/MeshLib/VtkOGSEnum.h
index 35d754f8626..ffe516441d9 100644
--- a/MeshLib/VtkOGSEnum.h
+++ b/MeshLib/VtkOGSEnum.h
@@ -7,13 +7,10 @@
  *
  */
 
-#ifndef VTKOGSENUM_H_
-#define VTKOGSENUM_H_
+#pragma once
 
 #include "MeshEnums.h"
 
 MeshLib::CellType VtkCellTypeToOGS(int type);
 
 int OGSToVtkCellType(MeshLib::CellType ogs);
-
-#endif // VTKOGSENUM_H_
diff --git a/MeshLib/convertMeshToGeo.h b/MeshLib/convertMeshToGeo.h
index dc8e595c62e..73923a292cb 100644
--- a/MeshLib/convertMeshToGeo.h
+++ b/MeshLib/convertMeshToGeo.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef CONVERTMESHTOGEO_H_
-#define CONVERTMESHTOGEO_H_
+#pragma once
 
 #include <limits>
 #include <string>
@@ -48,5 +47,3 @@ namespace MeshLib
     MeshLib::Mesh* convertSurfaceToMesh(const GeoLib::Surface &sfc, const std::string &mesh_name, double eps = std::numeric_limits<double>::epsilon());
 
 } // namespace
-
-#endif /* CONVERTMESHTOGEO_H_ */
diff --git a/NumLib/Assembler/SerialExecutor.h b/NumLib/Assembler/SerialExecutor.h
index 1942ca529cd..97755eb72f1 100644
--- a/NumLib/Assembler/SerialExecutor.h
+++ b/NumLib/Assembler/SerialExecutor.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef NUMLIB_SERIALEXECUTOR_H_H
-#define NUMLIB_SERIALEXECUTOR_H_H
+#pragma once
 
 namespace NumLib
 {
@@ -128,5 +127,3 @@ struct SerialExecutor
 };
 
 }   // namespace NumLib
-
-#endif  // NUMLIB_SERIALEXECUTOR_H_H
diff --git a/NumLib/DOF/ComponentGlobalIndexDict.h b/NumLib/DOF/ComponentGlobalIndexDict.h
index 0e704b4c867..e844601c7e2 100644
--- a/NumLib/DOF/ComponentGlobalIndexDict.h
+++ b/NumLib/DOF/ComponentGlobalIndexDict.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef NUMLIB_COMPONENTGLOBALINDEXDICT_H_
-#define NUMLIB_COMPONENTGLOBALINDEXDICT_H_
+#pragma once
 
 #include <limits>
 
@@ -119,5 +118,3 @@ typedef boost::multi_index::multi_index_container<
 
 }    // namespace detail
 }    // namespace NumLib
-
-#endif  // NUMLIB_COMPONENTGLOBALINDEXDICT_H_
diff --git a/NumLib/DOF/ComputeSparsityPattern.h b/NumLib/DOF/ComputeSparsityPattern.h
index 7b3e4cbb01b..15599531b61 100644
--- a/NumLib/DOF/ComputeSparsityPattern.h
+++ b/NumLib/DOF/ComputeSparsityPattern.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_COMPUTESPARSITYPATTERN_H
-#define NUMLIB_COMPUTESPARSITYPATTERN_H
+#pragma once
 
 #include <vector>
 
@@ -34,6 +33,3 @@ class LocalToGlobalIndexMap;
 GlobalSparsityPattern computeSparsityPattern(
     LocalToGlobalIndexMap const& dof_table, MeshLib::Mesh const& mesh);
 }
-
-#endif // NUMLIB_COMPUTESPARSITYPATTERN_H
-
diff --git a/NumLib/DOF/DOFTableUtil.h b/NumLib/DOF/DOFTableUtil.h
index 1fc5ee5ecae..1e28a3132d5 100644
--- a/NumLib/DOF/DOFTableUtil.h
+++ b/NumLib/DOF/DOFTableUtil.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_DOF_DOFTABLEUTIL_H
-#define NUMLIB_DOF_DOFTABLEUTIL_H
+#pragma once
 
 #include "MathLib/LinAlg/LinAlgEnums.h"
 #include "NumLib/DOF/LocalToGlobalIndexMap.h"
@@ -44,5 +43,3 @@ double norm(GlobalVector const& x, unsigned const global_component,
             LocalToGlobalIndexMap const& dof_table, MeshLib::Mesh const& mesh);
 
 }  // namespace NumLib
-
-#endif  // NUMLIB_DOF_DOFTABLEUTIL_H
diff --git a/NumLib/DOF/GlobalMatrixProviders.h b/NumLib/DOF/GlobalMatrixProviders.h
index 377eacb9729..fcde67cae0e 100644
--- a/NumLib/DOF/GlobalMatrixProviders.h
+++ b/NumLib/DOF/GlobalMatrixProviders.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_GLOBAL_MATRIX_PROVIDERS
-#define NUMLIB_GLOBAL_MATRIX_PROVIDERS
+#pragma once
 
 #include "MatrixProviderUser.h"
 
@@ -27,5 +26,3 @@ struct GlobalMatrixProvider
 void cleanupGlobalMatrixProviders();
 
 } // MathLib
-
-#endif // NUMLIB_GLOBAL_MATRIX_PROVIDERS
diff --git a/NumLib/DOF/LocalToGlobalIndexMap.h b/NumLib/DOF/LocalToGlobalIndexMap.h
index 4c8b145ffc0..0fe84a9084b 100644
--- a/NumLib/DOF/LocalToGlobalIndexMap.h
+++ b/NumLib/DOF/LocalToGlobalIndexMap.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_LOCALTOGLOBALINDEXMAP_H_
-#define NUMLIB_LOCALTOGLOBALINDEXMAP_H_
+#pragma once
 
 #ifndef NDEBUG
 #include <iosfwd>
@@ -220,5 +219,3 @@ private:
 };
 
 }   // namespace NumLib
-
-#endif  // NUMLIB_LOCALTOGLOBALINDEXMAP_H_
diff --git a/NumLib/DOF/MatrixProviderUser.h b/NumLib/DOF/MatrixProviderUser.h
index 5f94cba278c..945ebedadbb 100644
--- a/NumLib/DOF/MatrixProviderUser.h
+++ b/NumLib/DOF/MatrixProviderUser.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_MATRIX_PROVIDER_USER_H
-#define NUMLIB_MATRIX_PROVIDER_USER_H
+#pragma once
 
 #include <cstddef>
 
@@ -117,5 +116,3 @@ public:
 };
 
 } // namespace NumLib
-
-#endif // NUMLIB_MATRIX_PROVIDER_USER_H
diff --git a/NumLib/DOF/MeshComponentMap.h b/NumLib/DOF/MeshComponentMap.h
index 5d4e7d6232f..465cd3127ff 100644
--- a/NumLib/DOF/MeshComponentMap.h
+++ b/NumLib/DOF/MeshComponentMap.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef NUMLIB_MESHCOMPONENTMAP_H_
-#define NUMLIB_MESHCOMPONENTMAP_H_
+#pragma once
 
 #include "ComponentGlobalIndexDict.h"
 
@@ -192,5 +191,3 @@ private:
 };
 
 }   // namespace NumLib
-
-#endif  // NUMLIB_MESHCOMPONENTMAP_H_
diff --git a/NumLib/DOF/SimpleMatrixVectorProvider.h b/NumLib/DOF/SimpleMatrixVectorProvider.h
index 8a4c2f613f8..c288742d200 100644
--- a/NumLib/DOF/SimpleMatrixVectorProvider.h
+++ b/NumLib/DOF/SimpleMatrixVectorProvider.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_SIMPLE_MATRIX_PROVIDER_H
-#define NUMLIB_SIMPLE_MATRIX_PROVIDER_H
+#pragma once
 
 #include <map>
 #include <memory>
@@ -88,5 +87,3 @@ private:
 
 
 } // namespace NumLib
-
-#endif // NUMLIB_SIMPLE_MATRIX_PROVIDER_H
diff --git a/NumLib/Distribution/Distribution.h b/NumLib/Distribution/Distribution.h
index c9b2d285da4..0c38faded61 100644
--- a/NumLib/Distribution/Distribution.h
+++ b/NumLib/Distribution/Distribution.h
@@ -7,9 +7,7 @@
  *
  */
 
-
-#ifndef DISTRIBUTION_H_
-#define DISTRIBUTION_H_
+#pragma once
 
 #include <vector>
 
@@ -36,5 +34,3 @@ std::vector<double> generateNodeValueDistribution(
     const std::vector<std::size_t> &vec_node_ids);
 
 } // NumLib
-
-#endif // DISTRIBUTION_H_
diff --git a/NumLib/Extrapolation/ExtrapolatableElement.h b/NumLib/Extrapolation/ExtrapolatableElement.h
index 3a67de03cab..1ecfa992af3 100644
--- a/NumLib/Extrapolation/ExtrapolatableElement.h
+++ b/NumLib/Extrapolation/ExtrapolatableElement.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_EXTRAPOLATION_EXTRAPOLATABLEELEMENT_H
-#define NUMLIB_EXTRAPOLATION_EXTRAPOLATABLEELEMENT_H
+#pragma once
 
 #include <Eigen/Core>
 
@@ -31,5 +30,3 @@ public:
 };
 
 }  // namespace NumLib
-
-#endif  // NUMLIB_EXTRAPOLATION_EXTRAPOLATABLEELEMENT_H
diff --git a/NumLib/Extrapolation/ExtrapolatableElementCollection.h b/NumLib/Extrapolation/ExtrapolatableElementCollection.h
index 7f8a0adeb92..c07d719a79a 100644
--- a/NumLib/Extrapolation/ExtrapolatableElementCollection.h
+++ b/NumLib/Extrapolation/ExtrapolatableElementCollection.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_EXTRAPOLATION_EXTRAPOLATABLEELEMENTCOLLECTION_H
-#define NUMLIB_EXTRAPOLATION_EXTRAPOLATABLEELEMENTCOLLECTION_H
+#pragma once
 
 #include <vector>
 #include "ExtrapolatableElement.h"
@@ -131,5 +130,3 @@ makeExtrapolatable(LocalAssemblerCollection const& local_assemblers,
         local_assemblers, integration_point_values_method};
 }
 }  // namespace NumLib
-
-#endif  // NUMLIB_EXTRAPOLATION_EXTRAPOLATABLEELEMENTCOLLECTION_H
diff --git a/NumLib/Extrapolation/Extrapolator.h b/NumLib/Extrapolation/Extrapolator.h
index 58f4ba05414..fa13cace483 100644
--- a/NumLib/Extrapolation/Extrapolator.h
+++ b/NumLib/Extrapolation/Extrapolator.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_EXTRAPOLATOR_H
-#define NUMLIB_EXTRAPOLATOR_H
+#pragma once
 
 #include <vector>
 
@@ -49,5 +48,3 @@ public:
 };
 
 } // namespace ProcessLib
-
-#endif // NUMLIB_EXTRAPOLATOR_H
diff --git a/NumLib/Extrapolation/LocalLinearLeastSquaresExtrapolator.h b/NumLib/Extrapolation/LocalLinearLeastSquaresExtrapolator.h
index ee1981a2043..a5f58e2910b 100644
--- a/NumLib/Extrapolation/LocalLinearLeastSquaresExtrapolator.h
+++ b/NumLib/Extrapolation/LocalLinearLeastSquaresExtrapolator.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_LOCAL_LLSQ_EXTRAPOLATOR_H
-#define NUMLIB_LOCAL_LLSQ_EXTRAPOLATOR_H
+#pragma once
 
 #include <map>
 
@@ -123,5 +122,3 @@ private:
 };
 
 }  // namespace NumLib
-
-#endif  // NUMLIB_LOCAL_LLSQ_EXTRAPOLATOR_H
diff --git a/NumLib/Fem/CoordinatesMapping/NaturalCoordinatesMapping.h b/NumLib/Fem/CoordinatesMapping/NaturalCoordinatesMapping.h
index c4a4e3013cf..4da44b51b97 100644
--- a/NumLib/Fem/CoordinatesMapping/NaturalCoordinatesMapping.h
+++ b/NumLib/Fem/CoordinatesMapping/NaturalCoordinatesMapping.h
@@ -10,10 +10,7 @@
  *
  */
 
-
-#ifndef NATURALCOORDINATESMAPPING_H_
-#define NATURALCOORDINATESMAPPING_H_
-
+#pragma once
 
 #include "ShapeMatrices.h"
 
@@ -88,5 +85,3 @@ struct NaturalCoordinatesMapping
 };
 
 } // NumLib
-
-#endif //NATURALCOORDINATESMAPPING_H_
diff --git a/NumLib/Fem/CoordinatesMapping/ShapeMatrices.h b/NumLib/Fem/CoordinatesMapping/ShapeMatrices.h
index 77ff3f79bd5..a74020f8259 100644
--- a/NumLib/Fem/CoordinatesMapping/ShapeMatrices.h
+++ b/NumLib/Fem/CoordinatesMapping/ShapeMatrices.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef SHAPEMATRICES_H_
-#define SHAPEMATRICES_H_
+#pragma once
 
 #include <ostream>
 
@@ -110,5 +109,3 @@ struct ShapeMatrices
 } // NumLib
 
 #include "ShapeMatrices-impl.h"
-
-#endif //SHAPEMATRICES_H_
diff --git a/NumLib/Fem/FiniteElement/C0IsoparametricElements.h b/NumLib/Fem/FiniteElement/C0IsoparametricElements.h
index 6ffe766c61e..52b865bcec0 100644
--- a/NumLib/Fem/FiniteElement/C0IsoparametricElements.h
+++ b/NumLib/Fem/FiniteElement/C0IsoparametricElements.h
@@ -10,9 +10,7 @@
  *
  */
 
-
-#ifndef C0ISOPARAMETRICELEMENTS_H_
-#define C0ISOPARAMETRICELEMENTS_H_
+#pragma once
 
 #include "NumLib/Fem/ShapeFunction/ShapePoint1.h"
 #include "NumLib/Fem/ShapeFunction/ShapeLine2.h"
@@ -133,5 +131,3 @@ struct FePYRA13
 };
 
 } // NumLib
-
-#endif //C0ISOPARAMETRICELEMENTS_H_
diff --git a/NumLib/Fem/FiniteElement/LowerDimShapeTable.h b/NumLib/Fem/FiniteElement/LowerDimShapeTable.h
index e4fa78e9a4f..3f5166d3704 100644
--- a/NumLib/Fem/FiniteElement/LowerDimShapeTable.h
+++ b/NumLib/Fem/FiniteElement/LowerDimShapeTable.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUM_LIB_FEM_FINITE_ELEMENT_LOWERSHAPETABLE_H_
-#define NUM_LIB_FEM_FINITE_ELEMENT_LOWERSHAPETABLE_H_
+#pragma once
 
 #include "NumLib/Fem/ShapeFunction/ShapeHex20.h"
 #include "NumLib/Fem/ShapeFunction/ShapeHex8.h"
@@ -73,5 +72,3 @@ struct LowerDim<NumLib::ShapePyra13>
 };
 
 }  // namespace NumLib
-
-#endif  // NUM_LIB_FEM_FINITE_ELEMENT_LOWERSHAPETABLE_H_
diff --git a/NumLib/Fem/FiniteElement/TemplateIsoparametric.h b/NumLib/Fem/FiniteElement/TemplateIsoparametric.h
index 317021d7336..a62e301d398 100644
--- a/NumLib/Fem/FiniteElement/TemplateIsoparametric.h
+++ b/NumLib/Fem/FiniteElement/TemplateIsoparametric.h
@@ -10,10 +10,7 @@
  *
  */
 
-
-#ifndef TEMPLATEISOPARAMETRIC_H_
-#define TEMPLATEISOPARAMETRIC_H_
-
+#pragma once
 
 #include <cassert>
 #include <boost/math/constants/constants.hpp>
@@ -152,5 +149,3 @@ private:
 };
 
 } // NumLib
-
-#endif //TEMPLATEISOPARAMETRIC_H_
diff --git a/NumLib/Fem/Integration/GaussIntegrationPolicy.h b/NumLib/Fem/Integration/GaussIntegrationPolicy.h
index 051009599bb..d2cd2d10fb6 100644
--- a/NumLib/Fem/Integration/GaussIntegrationPolicy.h
+++ b/NumLib/Fem/Integration/GaussIntegrationPolicy.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_GAUSSINTEGRATIONPOLICY_H_
-#define NUMLIB_GAUSSINTEGRATIONPOLICY_H_
+#pragma once
 
 #include "MeshLib/Elements/Point.h"
 #include "MeshLib/Elements/Tri.h"
@@ -106,5 +105,3 @@ struct GaussIntegrationPolicy<MeshLib::Pyramid13>
 };
 
 }   // namespace NumLib
-
-#endif  // NUMLIB_GAUSSINTEGRATIONPOLICY_H_
diff --git a/NumLib/Fem/Integration/IntegrationGaussPrism.h b/NumLib/Fem/Integration/IntegrationGaussPrism.h
index 5408305ee34..f2fdb573b6f 100644
--- a/NumLib/Fem/Integration/IntegrationGaussPrism.h
+++ b/NumLib/Fem/Integration/IntegrationGaussPrism.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef INTEGRATIONGAUSSPRISM_H_
-#define INTEGRATIONGAUSSPRISM_H_
+#pragma once
 
 #include "MathLib/Integration/GaussLegendre.h"
 #include "MathLib/Integration/GaussLegendreTri.h"
@@ -96,5 +95,3 @@ private:
 };
 
 }
-
-#endif //INTEGRATIONGAUSSPRISM_H_
diff --git a/NumLib/Fem/Integration/IntegrationGaussPyramid.h b/NumLib/Fem/Integration/IntegrationGaussPyramid.h
index 745679e0129..d8e0707f47c 100644
--- a/NumLib/Fem/Integration/IntegrationGaussPyramid.h
+++ b/NumLib/Fem/Integration/IntegrationGaussPyramid.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef INTEGRATIONGAUSSPYRAMID_H_
-#define INTEGRATIONGAUSSPYRAMID_H_
+#pragma once
 
 #include "MathLib/Integration/GaussLegendrePyramid.h"
 
@@ -109,5 +108,3 @@ private:
 };
 
 }
-
-#endif //INTEGRATIONGAUSSPYRAMID_H_
diff --git a/NumLib/Fem/Integration/IntegrationGaussRegular.h b/NumLib/Fem/Integration/IntegrationGaussRegular.h
index 116d992187e..750ccf06dd6 100644
--- a/NumLib/Fem/Integration/IntegrationGaussRegular.h
+++ b/NumLib/Fem/Integration/IntegrationGaussRegular.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef INTEGRATIONGAUSSREGULAR_H_
-#define INTEGRATIONGAUSSREGULAR_H_
+#pragma once
 
 #include <cmath>
 #include <array>
@@ -98,5 +97,3 @@ private:
 } // NumLib
 
 #include "IntegrationGaussRegular-impl.h"
-
-#endif //INTEGRATIONGAUSSREGULAR_H_
diff --git a/NumLib/Fem/Integration/IntegrationGaussTet.h b/NumLib/Fem/Integration/IntegrationGaussTet.h
index c8d234af115..29e93014463 100644
--- a/NumLib/Fem/Integration/IntegrationGaussTet.h
+++ b/NumLib/Fem/Integration/IntegrationGaussTet.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef INTEGRATIONGAUSSTET_H_
-#define INTEGRATIONGAUSSTET_H_
+#pragma once
 
 #include "MathLib/Integration/GaussLegendreTet.h"
 
@@ -109,5 +108,3 @@ private:
 };
 
 }
-
-#endif //INTEGRATIONGAUSSTET_H_
diff --git a/NumLib/Fem/Integration/IntegrationGaussTri.h b/NumLib/Fem/Integration/IntegrationGaussTri.h
index 8f59726e1a7..6d66790dd88 100644
--- a/NumLib/Fem/Integration/IntegrationGaussTri.h
+++ b/NumLib/Fem/Integration/IntegrationGaussTri.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef INTEGRATIONGAUSSTRI_H_
-#define INTEGRATIONGAUSSTRI_H_
+#pragma once
 
 #include "MathLib/Integration/GaussLegendreTri.h"
 
@@ -125,5 +124,3 @@ private:
 };
 
 }
-
-#endif //INTEGRATIONGAUSSTRI_H_
diff --git a/NumLib/Fem/Integration/IntegrationPoint.h b/NumLib/Fem/Integration/IntegrationPoint.h
index ee639c38f0a..eaaee68924b 100644
--- a/NumLib/Fem/Integration/IntegrationPoint.h
+++ b/NumLib/Fem/Integration/IntegrationPoint.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_INTEGRATIONPOINT_H_
-#define NUMLIB_INTEGRATIONPOINT_H_
+#pragma once
 
 namespace NumLib
 {
@@ -74,5 +73,3 @@ public:
     }
 };
 }
-
-#endif  // NUMLIB_INTEGRATIONPOINT_H_
diff --git a/NumLib/Fem/ShapeFunction/ShapeHex20.h b/NumLib/Fem/ShapeFunction/ShapeHex20.h
index 295099d9e80..bcf4f111cb0 100644
--- a/NumLib/Fem/ShapeFunction/ShapeHex20.h
+++ b/NumLib/Fem/ShapeFunction/ShapeHex20.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef SHAPEHEX20_H_
-#define SHAPEHEX20_H_
+#pragma once
 
 #include "MeshLib/Elements/Hex.h"
 
@@ -48,5 +47,3 @@ public:
 }
 
 #include "ShapeHex20-impl.h"
-
-#endif //SHAPEHEX20_H_
diff --git a/NumLib/Fem/ShapeFunction/ShapeHex8.h b/NumLib/Fem/ShapeFunction/ShapeHex8.h
index 7ff7f3373f8..96ed9b09e5c 100644
--- a/NumLib/Fem/ShapeFunction/ShapeHex8.h
+++ b/NumLib/Fem/ShapeFunction/ShapeHex8.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef SHAPEHEX8_H_
-#define SHAPEHEX8_H_
+#pragma once
 
 #include "MeshLib/Elements/Hex.h"
 
@@ -66,5 +65,3 @@ public:
 }
 
 #include "ShapeHex8-impl.h"
-
-#endif //SHAPEHEX8_H_
diff --git a/NumLib/Fem/ShapeFunction/ShapeLine2.h b/NumLib/Fem/ShapeFunction/ShapeLine2.h
index 8a5b59c181c..738351ec08d 100644
--- a/NumLib/Fem/ShapeFunction/ShapeLine2.h
+++ b/NumLib/Fem/ShapeFunction/ShapeLine2.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef SHAPELINE2_H_
-#define SHAPELINE2_H_
+#pragma once
 
 #include "MeshLib/Elements/Line.h"
 
@@ -52,5 +51,3 @@ public:
 }
 
 #include "ShapeLine2-impl.h"
-
-#endif //SHAPELINE2_H_
diff --git a/NumLib/Fem/ShapeFunction/ShapeLine3.h b/NumLib/Fem/ShapeFunction/ShapeLine3.h
index 63f0cd7d349..2633edd744c 100644
--- a/NumLib/Fem/ShapeFunction/ShapeLine3.h
+++ b/NumLib/Fem/ShapeFunction/ShapeLine3.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef SHAPELINE3_H_
-#define SHAPELINE3_H_
+#pragma once
 
 #include "MeshLib/Elements/Line.h"
 
@@ -47,5 +46,3 @@ public:
 }
 
 #include "ShapeLine3-impl.h"
-
-#endif //SHAPELINE3_H_
diff --git a/NumLib/Fem/ShapeFunction/ShapePoint1.h b/NumLib/Fem/ShapeFunction/ShapePoint1.h
index b7bc9c239af..fec749f9e45 100644
--- a/NumLib/Fem/ShapeFunction/ShapePoint1.h
+++ b/NumLib/Fem/ShapeFunction/ShapePoint1.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef SHAPEPOINT1_H_
-#define SHAPEPOINT1_H_
+#pragma once
 
 #include "MeshLib/Elements/Point.h"
 
@@ -32,5 +31,3 @@ public:
 }
 
 #include "ShapePoint1-impl.h"
-
-#endif  // SHAPEPOINT1_H_
diff --git a/NumLib/Fem/ShapeFunction/ShapePrism15.h b/NumLib/Fem/ShapeFunction/ShapePrism15.h
index 148e663d345..8be25e633dc 100644
--- a/NumLib/Fem/ShapeFunction/ShapePrism15.h
+++ b/NumLib/Fem/ShapeFunction/ShapePrism15.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef SHAPEPRISM15_H_
-#define SHAPEPRISM15_H_
+#pragma once
 
 #include "MeshLib/Elements/Prism.h"
 
@@ -48,5 +47,3 @@ public:
 }
 
 #include "ShapePrism15-impl.h"
-
-#endif //SHAPEPRISM15_H_
diff --git a/NumLib/Fem/ShapeFunction/ShapePrism6.h b/NumLib/Fem/ShapeFunction/ShapePrism6.h
index 0343ed667d5..06e53967ae1 100644
--- a/NumLib/Fem/ShapeFunction/ShapePrism6.h
+++ b/NumLib/Fem/ShapeFunction/ShapePrism6.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef SHAPEPRISM6_H_
-#define SHAPEPRISM6_H_
+#pragma once
 
 #include "MeshLib/Elements/Prism.h"
 
@@ -48,5 +47,3 @@ public:
 }
 
 #include "ShapePrism6-impl.h"
-
-#endif //SHAPEPRISM6_H_
diff --git a/NumLib/Fem/ShapeFunction/ShapePyra13.h b/NumLib/Fem/ShapeFunction/ShapePyra13.h
index 57a2519ef13..e3092de9637 100644
--- a/NumLib/Fem/ShapeFunction/ShapePyra13.h
+++ b/NumLib/Fem/ShapeFunction/ShapePyra13.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef SHAPEPYRA13_H_
-#define SHAPEPYRA13_H_
+#pragma once
 
 #include "MeshLib/Elements/Pyramid.h"
 
@@ -48,5 +47,3 @@ public:
 }
 
 #include "ShapePyra13-impl.h"
-
-#endif //SHAPEPYRA13_H_
diff --git a/NumLib/Fem/ShapeFunction/ShapePyra5.h b/NumLib/Fem/ShapeFunction/ShapePyra5.h
index cc0f6c882f6..7c7c1ba5c74 100644
--- a/NumLib/Fem/ShapeFunction/ShapePyra5.h
+++ b/NumLib/Fem/ShapeFunction/ShapePyra5.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef SHAPEPYRA5_H_
-#define SHAPEPYRA5_H_
+#pragma once
 
 #include "MeshLib/Elements/Pyramid.h"
 
@@ -48,5 +47,3 @@ public:
 }
 
 #include "ShapePyra5-impl.h"
-
-#endif //SHAPEPYRA5_H_
diff --git a/NumLib/Fem/ShapeFunction/ShapeQuad4.h b/NumLib/Fem/ShapeFunction/ShapeQuad4.h
index fda3408783c..c904fffcaa5 100644
--- a/NumLib/Fem/ShapeFunction/ShapeQuad4.h
+++ b/NumLib/Fem/ShapeFunction/ShapeQuad4.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef SHAPEQUAD4_H_
-#define SHAPEQUAD4_H_
+#pragma once
 
 #include "MeshLib/Elements/Quad.h"
 
@@ -60,5 +59,3 @@ public:
 }
 
 #include "ShapeQuad4-impl.h"
-
-#endif //SHAPEQUAD4_H_
diff --git a/NumLib/Fem/ShapeFunction/ShapeQuad8.h b/NumLib/Fem/ShapeFunction/ShapeQuad8.h
index 10c54957ff6..01a5a8a56ab 100644
--- a/NumLib/Fem/ShapeFunction/ShapeQuad8.h
+++ b/NumLib/Fem/ShapeFunction/ShapeQuad8.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef SHAPEQUAD8_H_
-#define SHAPEQUAD8_H_
+#pragma once
 
 #include "MeshLib/Elements/Quad.h"
 
@@ -47,5 +46,3 @@ public:
 }
 
 #include "ShapeQuad8-impl.h"
-
-#endif //SHAPEQUAD8_H_
diff --git a/NumLib/Fem/ShapeFunction/ShapeQuad9.h b/NumLib/Fem/ShapeFunction/ShapeQuad9.h
index 93e00191d4d..9140f1e27d3 100644
--- a/NumLib/Fem/ShapeFunction/ShapeQuad9.h
+++ b/NumLib/Fem/ShapeFunction/ShapeQuad9.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef SHAPEQUAD9_H_
-#define SHAPEQUAD9_H_
+#pragma once
 
 #include "MeshLib/Elements/Quad.h"
 
@@ -47,5 +46,3 @@ public:
 }
 
 #include "ShapeQuad9-impl.h"
-
-#endif //SHAPEQUAD9_H_
diff --git a/NumLib/Fem/ShapeFunction/ShapeTet10.h b/NumLib/Fem/ShapeFunction/ShapeTet10.h
index b93f52d75f5..7c9a7ceab50 100644
--- a/NumLib/Fem/ShapeFunction/ShapeTet10.h
+++ b/NumLib/Fem/ShapeFunction/ShapeTet10.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef SHAPETET10_H_
-#define SHAPETET10_H_
+#pragma once
 
 #include "MeshLib/Elements/Tet.h"
 
@@ -48,5 +47,3 @@ public:
 }
 
 #include "ShapeTet10-impl.h"
-
-#endif //SHAPETET10_H_
diff --git a/NumLib/Fem/ShapeFunction/ShapeTet4.h b/NumLib/Fem/ShapeFunction/ShapeTet4.h
index e505cdbae3d..65039e06ff3 100644
--- a/NumLib/Fem/ShapeFunction/ShapeTet4.h
+++ b/NumLib/Fem/ShapeFunction/ShapeTet4.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef SHAPETET4_H_
-#define SHAPETET4_H_
+#pragma once
 
 #include "MeshLib/Elements/Tet.h"
 
@@ -48,5 +47,3 @@ public:
 }
 
 #include "ShapeTet4-impl.h"
-
-#endif //SHAPETET4_H_
diff --git a/NumLib/Fem/ShapeFunction/ShapeTri3.h b/NumLib/Fem/ShapeFunction/ShapeTri3.h
index c0291641b2c..1e85878ead1 100644
--- a/NumLib/Fem/ShapeFunction/ShapeTri3.h
+++ b/NumLib/Fem/ShapeFunction/ShapeTri3.h
@@ -12,8 +12,7 @@
  *
  */
 
-#ifndef SHAPETRI3_H_
-#define SHAPETRI3_H_
+#pragma once
 
 #include "MeshLib/Elements/Tri.h"
 
@@ -61,5 +60,3 @@ public:
 }
 
 #include "ShapeTri3-impl.h"
-
-#endif //SHAPETRI3_H_
diff --git a/NumLib/Fem/ShapeFunction/ShapeTri6.h b/NumLib/Fem/ShapeFunction/ShapeTri6.h
index aa0eafd49c1..c3d7e67b0c8 100644
--- a/NumLib/Fem/ShapeFunction/ShapeTri6.h
+++ b/NumLib/Fem/ShapeFunction/ShapeTri6.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef SHAPETRI6_H_
-#define SHAPETRI6_H_
+#pragma once
 
 #include "MeshLib/Elements/Tri.h"
 
@@ -49,5 +48,3 @@ public:
 }
 
 #include "ShapeTri6-impl.h"
-
-#endif //SHAPETRI6_H_
diff --git a/NumLib/Fem/ShapeMatrixPolicy.h b/NumLib/Fem/ShapeMatrixPolicy.h
index b9222e662ed..3fe0eda7448 100644
--- a/NumLib/Fem/ShapeMatrixPolicy.h
+++ b/NumLib/Fem/ShapeMatrixPolicy.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef SHAPE_MATRIX_POLICY_H_
-#define SHAPE_MATRIX_POLICY_H_
+#pragma once
 
 #include "NumLib/Fem/CoordinatesMapping/ShapeMatrices.h"
 
@@ -132,5 +131,3 @@ const unsigned OGS_EIGEN_DYNAMIC_SHAPE_MATRICES_FLAG = 0;
 
 //static_assert(std::is_class<ShapeMatrixPolicyType<>::value,
         //"ShapeMatrixPolicyType was not defined.");
-
-#endif  // SHAPE_MATRIX_POLICY_H_
diff --git a/NumLib/Function/ISpatialFunction.h b/NumLib/Function/ISpatialFunction.h
index fc92a01f189..0d3b37ab76b 100644
--- a/NumLib/Function/ISpatialFunction.h
+++ b/NumLib/Function/ISpatialFunction.h
@@ -10,9 +10,7 @@
  *
  */
 
-
-#ifndef ISPATIALFUNCTION_H_
-#define ISPATIALFUNCTION_H_
+#pragma once
 
 #include <vector>
 
@@ -38,5 +36,3 @@ public:
 };
 
 } // NumLib
-
-#endif //ISPATIALFUNCTION_H_
diff --git a/NumLib/Function/Interpolation.h b/NumLib/Function/Interpolation.h
index 530a5647994..74955437c45 100644
--- a/NumLib/Function/Interpolation.h
+++ b/NumLib/Function/Interpolation.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_INTERPOLATION_H
-#define NUMLIB_INTERPOLATION_H
+#pragma once
 
 #include<array>
 #include<cassert>
@@ -86,5 +85,3 @@ void shapeFunctionInterpolate(
 }
 
 } // namespace NumLib
-
-#endif // NUMLIB_INTERPOLATION_H
diff --git a/NumLib/Function/LinearInterpolationAlongPolyline.h b/NumLib/Function/LinearInterpolationAlongPolyline.h
index e710b39438c..1e214df96f6 100644
--- a/NumLib/Function/LinearInterpolationAlongPolyline.h
+++ b/NumLib/Function/LinearInterpolationAlongPolyline.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef LINEARINTERPOLATIONALONGPOLYLINE_H_
-#define LINEARINTERPOLATIONALONGPOLYLINE_H_
+#pragma once
 
 #include <vector>
 
@@ -77,6 +76,3 @@ private:
 };
 
 } // NumLib
-
-#endif //LINEARINTERPOLATIONALONGPOLYLINE_H_
-
diff --git a/NumLib/Function/LinearInterpolationOnSurface.h b/NumLib/Function/LinearInterpolationOnSurface.h
index 453612c3e5c..6529d273985 100644
--- a/NumLib/Function/LinearInterpolationOnSurface.h
+++ b/NumLib/Function/LinearInterpolationOnSurface.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef LINEARINTERPOLATIONSURFACE_H_
-#define LINEARINTERPOLATIONSURFACE_H_
+#pragma once
 
 #include <vector>
 
@@ -96,6 +95,3 @@ private:
 };
 
 } // NumLib
-
-#endif //LINEARINTERPOLATIONSURFACE_H_
-
diff --git a/NumLib/Function/SpatialFunctionLinear.h b/NumLib/Function/SpatialFunctionLinear.h
index a1393f70206..d8975b58b97 100644
--- a/NumLib/Function/SpatialFunctionLinear.h
+++ b/NumLib/Function/SpatialFunctionLinear.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef SPATIALFUNCTIONLINEAR_H_
-#define SPATIALFUNCTIONLINEAR_H_
+#pragma once
 
 #include "MathLib/LinearFunction.h"
 #include "TemplateSpatialFunction.h"
@@ -23,5 +22,3 @@ namespace NumLib
 typedef TemplateSpatialFunction<MathLib::LinearFunction<double, 3> > SpatialFunctionLinear;
 
 }
-
-#endif /* SPATIALFUNCTIONLINEAR_H_ */
diff --git a/NumLib/Function/TemplateSpatialFunction.h b/NumLib/Function/TemplateSpatialFunction.h
index 109447ea525..8b372e1d643 100644
--- a/NumLib/Function/TemplateSpatialFunction.h
+++ b/NumLib/Function/TemplateSpatialFunction.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef TEMPLATESPATIALFUNCTION_H_
-#define TEMPLATESPATIALFUNCTION_H_
+#pragma once
 
 #include "ISpatialFunction.h"
 
@@ -50,5 +49,3 @@ private:
 };
 
 }
-
-#endif /* TEMPLATESPATIALFUNCTION_H_ */
diff --git a/NumLib/IndexValueVector.h b/NumLib/IndexValueVector.h
index 4dd248418e2..713c1c1eb2c 100644
--- a/NumLib/IndexValueVector.h
+++ b/NumLib/IndexValueVector.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUM_LIB_INDEXVALUEVECTOR_H
-#define NUM_LIB_INDEXVALUEVECTOR_H
+#pragma once
 
 #include <vector>
 
@@ -23,5 +22,3 @@ struct IndexValueVector final
 };
 
 }
-
-#endif  // NUM_LIB_INDEXVALUEVECTOR_H
diff --git a/NumLib/NamedFunction.h b/NumLib/NamedFunction.h
index 1baa71c8e50..bea46bac736 100644
--- a/NumLib/NamedFunction.h
+++ b/NumLib/NamedFunction.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_NAMED_FUNCTION
-#define NUMLIB_NAMED_FUNCTION
+#pragma once
 
 #include <cassert>
 #include <functional>
@@ -112,5 +111,3 @@ NamedFunction::NamedFunction(std::string const& name,
 }
 
 }  // namespace NumLib
-
-#endif // NUMLIB_NAMED_FUNCTION
diff --git a/NumLib/NamedFunctionCaller.h b/NumLib/NamedFunctionCaller.h
index cef93d179d9..425c17ab4cc 100644
--- a/NumLib/NamedFunctionCaller.h
+++ b/NumLib/NamedFunctionCaller.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_NAMEDFUNCTIONCALLER_H
-#define NUMLIB_NAMEDFUNCTIONCALLER_H
+#pragma once
 
 #include <map>
 #include <vector>
@@ -124,7 +123,3 @@ private:
 };
 
 } // namespace NumLib
-
-
-
-#endif // NUMLIB_NAMEDFUNCTIONCALLER_H
diff --git a/NumLib/NamedFunctionProvider.h b/NumLib/NamedFunctionProvider.h
index 7263b9af708..bdb59ddc67b 100644
--- a/NumLib/NamedFunctionProvider.h
+++ b/NumLib/NamedFunctionProvider.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_NAMEDFUNCTIONPROVIDER_H
-#define NUMLIB_NAMEDFUNCTIONPROVIDER_H
+#pragma once
 
 #include "NamedFunction.h"
 
@@ -28,5 +27,3 @@ public:
 };
 
 } // namespace NumLib
-
-#endif // NUMLIB_NAMEDFUNCTIONPROVIDER_H
diff --git a/NumLib/NewtonRaphson.h b/NumLib/NewtonRaphson.h
index ad4fb7c3b2c..87af6ee8769 100644
--- a/NumLib/NewtonRaphson.h
+++ b/NumLib/NewtonRaphson.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_NEWTONRAPHSON_H_
-#define NUMLIB_NEWTONRAPHSON_H_
+#pragma once
 
 #include <boost/optional.hpp>
 #include <logog/include/logog.hpp>
@@ -91,5 +90,3 @@ private:
     const double _tolerance_squared;
 };
 }  // namespace NumLib
-
-#endif  // NUMLIB_NEWTONRAPHSON_H_
diff --git a/NumLib/NumericsConfig.h b/NumLib/NumericsConfig.h
index 7d262f047ae..da27bca6974 100644
--- a/NumLib/NumericsConfig.h
+++ b/NumLib/NumericsConfig.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_NUMERICSCONFIG_H_
-#define NUMLIB_NUMERICSCONFIG_H_
+#pragma once
 
 /**
  * This file provides a configuration of the global matrix/vector and
@@ -22,7 +21,3 @@
 //
 #include "NumLib/Assembler/SerialExecutor.h"
 using GlobalExecutor = NumLib::SerialExecutor;
-
-
-
-#endif  // NUMLIB_NUMERICSCONFIG_H_
diff --git a/NumLib/ODESolver/ConvergenceCriterion.h b/NumLib/ODESolver/ConvergenceCriterion.h
index 27240c8326b..dc9faa5a6de 100644
--- a/NumLib/ODESolver/ConvergenceCriterion.h
+++ b/NumLib/ODESolver/ConvergenceCriterion.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_CONVERGENCECRITERION_H
-#define NUMLIB_CONVERGENCECRITERION_H
+#pragma once
 
 #include <memory>
 #include "NumLib/NumericsConfig.h"
@@ -88,5 +87,3 @@ bool checkRelativeTolerance(double const reltol,
                             double const denominator);
 
 } // namespace NumLib
-
-#endif  // NUMLIB_CONVERGENCECRITERION_H
diff --git a/NumLib/ODESolver/ConvergenceCriterionDeltaX.h b/NumLib/ODESolver/ConvergenceCriterionDeltaX.h
index 89522995b8e..36fcb9380ef 100644
--- a/NumLib/ODESolver/ConvergenceCriterionDeltaX.h
+++ b/NumLib/ODESolver/ConvergenceCriterionDeltaX.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_CONVERGENCECRITERIONDELTAX_H
-#define NUMLIB_CONVERGENCECRITERIONDELTAX_H
+#pragma once
 
 #include <boost/optional.hpp>
 #include "ConvergenceCriterion.h"
@@ -50,5 +49,3 @@ std::unique_ptr<ConvergenceCriterionDeltaX> createConvergenceCriterionDeltaX(
     BaseLib::ConfigTree const& config);
 
 }  // NumLib
-
-#endif  // NUMLIB_CONVERGENCECRITERIONDELTAX_H
diff --git a/NumLib/ODESolver/ConvergenceCriterionPerComponent.h b/NumLib/ODESolver/ConvergenceCriterionPerComponent.h
index 19b30718f9c..0ff42fdebf1 100644
--- a/NumLib/ODESolver/ConvergenceCriterionPerComponent.h
+++ b/NumLib/ODESolver/ConvergenceCriterionPerComponent.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_CONVERGENCECRITERIONPERCOMPONENT_H
-#define NUMLIB_CONVERGENCECRITERIONPERCOMPONENT_H
+#pragma once
 
 #include "ConvergenceCriterion.h"
 
@@ -33,5 +32,3 @@ public:
 };
 
 }  // namespace NumLib
-
-#endif  // NUMLIB_CONVERGENCECRITERIONPERCOMPONENT_H
diff --git a/NumLib/ODESolver/ConvergenceCriterionPerComponentDeltaX.h b/NumLib/ODESolver/ConvergenceCriterionPerComponentDeltaX.h
index cb5eae19e5d..07edfb4b084 100644
--- a/NumLib/ODESolver/ConvergenceCriterionPerComponentDeltaX.h
+++ b/NumLib/ODESolver/ConvergenceCriterionPerComponentDeltaX.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_CONVERGENCECRITERIONPERCOMPONENTDELTAX_H
-#define NUMLIB_CONVERGENCECRITERIONPERCOMPONENTDELTAX_H
+#pragma once
 
 #include "MathLib/LinAlg/LinAlgEnums.h"
 #include "ConvergenceCriterionPerComponent.h"
@@ -58,5 +57,3 @@ std::unique_ptr<ConvergenceCriterionPerComponentDeltaX>
 createConvergenceCriterionPerComponentDeltaX(BaseLib::ConfigTree const& config);
 
 }  // namespace NumLib
-
-#endif  // NUMLIB_CONVERGENCECRITERIONPERCOMPONENTDELTAX_H
diff --git a/NumLib/ODESolver/ConvergenceCriterionPerComponentResidual.h b/NumLib/ODESolver/ConvergenceCriterionPerComponentResidual.h
index 2656cfca7b7..a20a6886a71 100644
--- a/NumLib/ODESolver/ConvergenceCriterionPerComponentResidual.h
+++ b/NumLib/ODESolver/ConvergenceCriterionPerComponentResidual.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_CONVERGENCECRITERIONPERCOMPONENTRESIDUAL_H
-#define NUMLIB_CONVERGENCECRITERIONPERCOMPONENTRESIDUAL_H
+#pragma once
 
 #include <vector>
 #include "MathLib/LinAlg/LinAlgEnums.h"
@@ -65,5 +64,3 @@ createConvergenceCriterionPerComponentResidual(
     BaseLib::ConfigTree const& config);
 
 }  // namespace NumLib
-
-#endif  // NUMLIB_CONVERGENCECRITERIONPERCOMPONENTRESIDUAL_H
diff --git a/NumLib/ODESolver/ConvergenceCriterionResidual.h b/NumLib/ODESolver/ConvergenceCriterionResidual.h
index accf03cdbe1..21b793f589d 100644
--- a/NumLib/ODESolver/ConvergenceCriterionResidual.h
+++ b/NumLib/ODESolver/ConvergenceCriterionResidual.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_CONVERGENCECRITERIONRESIDUAL_H
-#define NUMLIB_CONVERGENCECRITERIONRESIDUAL_H
+#pragma once
 
 #include <boost/optional.hpp>
 #include "ConvergenceCriterion.h"
@@ -55,5 +54,3 @@ std::unique_ptr<ConvergenceCriterionResidual> createConvergenceCriterionResidual
     BaseLib::ConfigTree const& config);
 
 }  // NumLib
-
-#endif  // NUMLIB_CONVERGENCECRITERIONRESIDUAL_H
diff --git a/NumLib/ODESolver/EquationSystem.h b/NumLib/ODESolver/EquationSystem.h
index dbdeaa44449..ba7bbcb74d0 100644
--- a/NumLib/ODESolver/EquationSystem.h
+++ b/NumLib/ODESolver/EquationSystem.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_EQUATIONSYSTEM_H
-#define NUMLIB_EQUATIONSYSTEM_H
+#pragma once
 
 #include "NumLib/DOF/MatrixProviderUser.h"
 
@@ -66,5 +65,3 @@ public:
 
 //! @}
 }
-
-#endif
diff --git a/NumLib/ODESolver/MatrixTranslator.h b/NumLib/ODESolver/MatrixTranslator.h
index 6960f904d33..f4edf65943b 100644
--- a/NumLib/ODESolver/MatrixTranslator.h
+++ b/NumLib/ODESolver/MatrixTranslator.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_MATRIXTRANSLATOR_H
-#define NUMLIB_MATRIXTRANSLATOR_H
+#pragma once
 
 #include <memory>
 
@@ -313,5 +312,3 @@ std::unique_ptr<MatrixTranslator<ODETag>> createMatrixTranslator(
 
 //! @}
 }
-
-#endif  // NUMLIB_MATRIXTRANSLATOR_H
diff --git a/NumLib/ODESolver/NonlinearSolver.h b/NumLib/ODESolver/NonlinearSolver.h
index 2a135ce101e..c4a9be12b97 100644
--- a/NumLib/ODESolver/NonlinearSolver.h
+++ b/NumLib/ODESolver/NonlinearSolver.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_NONLINEARSOLVER_H
-#define NUMLIB_NONLINEARSOLVER_H
+#pragma once
 
 #include <memory>
 #include <utility>
@@ -195,5 +194,3 @@ createNonlinearSolver(
 //! @}
 
 }  // namespace NumLib
-
-#endif  // NUMLIB_NONLINEARSOLVER_H
diff --git a/NumLib/ODESolver/NonlinearSystem.h b/NumLib/ODESolver/NonlinearSystem.h
index dcb38e36805..edfa53160ee 100644
--- a/NumLib/ODESolver/NonlinearSystem.h
+++ b/NumLib/ODESolver/NonlinearSystem.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_NONLINEARSYSTEM_H
-#define NUMLIB_NONLINEARSYSTEM_H
+#pragma once
 
 #include "EquationSystem.h"
 #include "Types.h"
@@ -97,5 +96,3 @@ public:
 
 //! @}
 }
-
-#endif  // NUMLIB_NONLINEARSYSTEM_H
diff --git a/NumLib/ODESolver/ODESystem.h b/NumLib/ODESolver/ODESystem.h
index 0a152879f55..aafe142c7a5 100644
--- a/NumLib/ODESolver/ODESystem.h
+++ b/NumLib/ODESolver/ODESystem.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_ODESYSTEM_H
-#define NUMLIB_ODESYSTEM_H
+#pragma once
 
 #include "MathLib/LinAlg/MatrixVectorTraits.h"
 #include "NumLib/IndexValueVector.h"
@@ -121,5 +120,3 @@ public:
 
 //! @}
 }
-
-#endif  // NUMLIB_ODESYSTEM_H
diff --git a/NumLib/ODESolver/TimeDiscretization.h b/NumLib/ODESolver/TimeDiscretization.h
index 354e980ca9c..ea6dd2ec6b6 100644
--- a/NumLib/ODESolver/TimeDiscretization.h
+++ b/NumLib/ODESolver/TimeDiscretization.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_TIMEDISCRETIZATION_H
-#define NUMLIB_TIMEDISCRETIZATION_H
+#pragma once
 
 #include <vector>
 
@@ -501,5 +500,3 @@ private:
 
 //! @}
 }
-
-#endif  // NUMLIB_TIMEDISCRETIZATION_H
diff --git a/NumLib/ODESolver/TimeDiscretizationBuilder.h b/NumLib/ODESolver/TimeDiscretizationBuilder.h
index 27b2d4bced2..9a34d1a49f5 100644
--- a/NumLib/ODESolver/TimeDiscretizationBuilder.h
+++ b/NumLib/ODESolver/TimeDiscretizationBuilder.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_TIMEDISCRETIZATION_BUILDER_H
-#define NUMLIB_TIMEDISCRETIZATION_BUILDER_H
+#pragma once
 
 #include <memory>
 
@@ -21,5 +20,3 @@ namespace NumLib
 std::unique_ptr<TimeDiscretization> createTimeDiscretization(
     BaseLib::ConfigTree const& config);
 }
-
-#endif  // NUMLIB_TIMEDISCRETIZATION_BUILDER_H
diff --git a/NumLib/ODESolver/TimeDiscretizedODESystem.h b/NumLib/ODESolver/TimeDiscretizedODESystem.h
index 0e80a99a48b..4a9856d0847 100644
--- a/NumLib/ODESolver/TimeDiscretizedODESystem.h
+++ b/NumLib/ODESolver/TimeDiscretizedODESystem.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_TIMEDISCRETIZEDODESYSTEM_H
-#define NUMLIB_TIMEDISCRETIZEDODESYSTEM_H
+#pragma once
 
 #include <memory>
 
@@ -234,5 +233,3 @@ private:
 
 //! @}
 }
-
-#endif  // NUMLIB_TIMEDISCRETIZEDODESYSTEM_H
diff --git a/NumLib/ODESolver/TimeLoopSingleODE.h b/NumLib/ODESolver/TimeLoopSingleODE.h
index ae860986c0d..f07da8a2076 100644
--- a/NumLib/ODESolver/TimeLoopSingleODE.h
+++ b/NumLib/ODESolver/TimeLoopSingleODE.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_TIMELOOP_H
-#define NUMLIB_TIMELOOP_H
+#pragma once
 
 #include "NumLib/DOF/GlobalMatrixProviders.h"
 #include "TimeDiscretizedODESystem.h"
@@ -134,5 +133,3 @@ bool TimeLoopSingleODE<NLTag>::loop(const double t0, GlobalVector const& x0,
     return nl_slv_succeeded;
 }
 }
-
-#endif  // NUMLIB_TIMELOOP_H
diff --git a/NumLib/ODESolver/Types.h b/NumLib/ODESolver/Types.h
index f0d58a6f822..cba55701b6a 100644
--- a/NumLib/ODESolver/Types.h
+++ b/NumLib/ODESolver/Types.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef NUMLIB_TYPES_H
-#define NUMLIB_TYPES_H
+#pragma once
 
 namespace NumLib
 {
@@ -38,5 +37,3 @@ enum class ODESystemTag : char
 //! @}
 
 } // namespace NumLib
-
-#endif // NUMLIB_TYPES_H
diff --git a/NumLib/TimeStepping/Algorithms/FixedTimeStepping.h b/NumLib/TimeStepping/Algorithms/FixedTimeStepping.h
index 851ecc1e520..af57f4f9ddb 100644
--- a/NumLib/TimeStepping/Algorithms/FixedTimeStepping.h
+++ b/NumLib/TimeStepping/Algorithms/FixedTimeStepping.h
@@ -9,8 +9,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef FIXEDTIMESTEPPING_H_
-#define FIXEDTIMESTEPPING_H_
+#pragma once
 
 #include <memory>
 #include <vector>
@@ -99,5 +98,3 @@ private:
 };
 
 } //NumLib
-
-#endif // FIXEDTIMESTEPPING_H_
diff --git a/NumLib/TimeStepping/Algorithms/ITimeStepAlgorithm.h b/NumLib/TimeStepping/Algorithms/ITimeStepAlgorithm.h
index a2572df2287..110aa331a5c 100644
--- a/NumLib/TimeStepping/Algorithms/ITimeStepAlgorithm.h
+++ b/NumLib/TimeStepping/Algorithms/ITimeStepAlgorithm.h
@@ -9,8 +9,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef ITIMESTEPALGORITHM_H_
-#define ITIMESTEPALGORITHM_H_
+#pragma once
 
 #include <vector>
 
@@ -49,5 +48,3 @@ public:
 };
 
 } //NumLib
-
-#endif //ITIMESTEPALGORITHM_H_
diff --git a/NumLib/TimeStepping/Algorithms/IterationNumberBasedAdaptiveTimeStepping.h b/NumLib/TimeStepping/Algorithms/IterationNumberBasedAdaptiveTimeStepping.h
index 16d38f414b4..fe2c3db2e7d 100644
--- a/NumLib/TimeStepping/Algorithms/IterationNumberBasedAdaptiveTimeStepping.h
+++ b/NumLib/TimeStepping/Algorithms/IterationNumberBasedAdaptiveTimeStepping.h
@@ -9,8 +9,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef ITERATIONNUMBERBASEDADAPTIVETIMESTEPPING_H_
-#define ITERATIONNUMBERBASEDADAPTIVETIMESTEPPING_H_
+#pragma once
 
 #include <vector>
 
@@ -142,5 +141,3 @@ private:
 };
 
 } // NumLib
-
-#endif // NEWTONADAPTIVETIMESTEPPING_H_
diff --git a/NumLib/TimeStepping/TimeStep.h b/NumLib/TimeStepping/TimeStep.h
index c7f53a94a14..07c66d869a4 100644
--- a/NumLib/TimeStepping/TimeStep.h
+++ b/NumLib/TimeStepping/TimeStep.h
@@ -9,8 +9,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef TIMESTEP_H_
-#define TIMESTEP_H_
+#pragma once
 
 #include <cstddef>
 
@@ -116,5 +115,3 @@ private:
 };
 
 } //NumLib
-
-#endif // TIMESTEP_H_
diff --git a/ProcessLib/AbstractJacobianAssembler.h b/ProcessLib/AbstractJacobianAssembler.h
index 412130f5679..7989d383b16 100644
--- a/ProcessLib/AbstractJacobianAssembler.h
+++ b/ProcessLib/AbstractJacobianAssembler.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_ABSTRACTJACOBIANASSEMBLER_H
-#define PROCESSLIB_ABSTRACTJACOBIANASSEMBLER_H
+#pragma once
 
 #include <vector>
 
@@ -34,5 +33,3 @@ public:
 };
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_ABSTRACTJACOBIANASSEMBLER_H
diff --git a/ProcessLib/AnalyticalJacobianAssembler.h b/ProcessLib/AnalyticalJacobianAssembler.h
index 1b04eb34e41..5de7476d929 100644
--- a/ProcessLib/AnalyticalJacobianAssembler.h
+++ b/ProcessLib/AnalyticalJacobianAssembler.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_ANALYTICALJACOBIANASSEMBLER_H
-#define PROCESSLIB_ANALYTICALJACOBIANASSEMBLER_H
+#pragma once
 
 #include "AbstractJacobianAssembler.h"
 
@@ -38,5 +37,3 @@ public:
 };
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_ANALYTICALJACOBIANASSEMBLER_H
diff --git a/ProcessLib/BoundaryCondition/BoundaryCondition.h b/ProcessLib/BoundaryCondition/BoundaryCondition.h
index ae2791336d4..ccf1b7ba364 100644
--- a/ProcessLib/BoundaryCondition/BoundaryCondition.h
+++ b/ProcessLib/BoundaryCondition/BoundaryCondition.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_BOUNDARYCONDITION_H
-#define PROCESSLIB_BOUNDARYCONDITION_H
+#pragma once
 
 #include "NumLib/NumericsConfig.h"
 
@@ -119,5 +118,3 @@ protected:
 };
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_BOUNDARYCONDITION_H
diff --git a/ProcessLib/BoundaryCondition/BoundaryConditionCollection.h b/ProcessLib/BoundaryCondition/BoundaryConditionCollection.h
index b3419075a31..e726ab7f5e0 100644
--- a/ProcessLib/BoundaryCondition/BoundaryConditionCollection.h
+++ b/ProcessLib/BoundaryCondition/BoundaryConditionCollection.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_BOUNDARYCONDITIONCOLLECTION_H
-#define PROCESSLIB_BOUNDARYCONDITIONCOLLECTION_H
+#pragma once
 
 #include "NumLib/IndexValueVector.h"
 #include "ProcessLib/ProcessVariable.h"
@@ -54,5 +53,3 @@ private:
 
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_BOUNDARYCONDITIONCOLLECTION_H
diff --git a/ProcessLib/BoundaryCondition/BoundaryConditionConfig.h b/ProcessLib/BoundaryCondition/BoundaryConditionConfig.h
index 5621cb27c7f..17bcb4aeae1 100644
--- a/ProcessLib/BoundaryCondition/BoundaryConditionConfig.h
+++ b/ProcessLib/BoundaryCondition/BoundaryConditionConfig.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_BOUNDARYCONDITIONCONFIG_H
-#define PROCESSLIB_BOUNDARYCONDITIONCONFIG_H
+#pragma once
 
 #include "BaseLib/ConfigTree.h"
 #include "GeoLib/GEOObjects.h"
@@ -40,5 +39,3 @@ struct BoundaryConditionConfig final
 };
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_BOUNDARYCONDITIONCONFIG_H
diff --git a/ProcessLib/BoundaryCondition/DirichletBoundaryCondition.h b/ProcessLib/BoundaryCondition/DirichletBoundaryCondition.h
index f38a2f1ecd8..ce485b3b7f0 100644
--- a/ProcessLib/BoundaryCondition/DirichletBoundaryCondition.h
+++ b/ProcessLib/BoundaryCondition/DirichletBoundaryCondition.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_DIRICHLETBOUNDARYCONDITION_H
-#define PROCESSLIB_DIRICHLETBOUNDARYCONDITION_H
+#pragma once
 
 #include "NumLib/DOF/LocalToGlobalIndexMap.h"
 #include "NumLib/IndexValueVector.h"
@@ -63,5 +62,3 @@ std::unique_ptr<DirichletBoundaryCondition> createDirichletBoundaryCondition(
     const std::vector<std::unique_ptr<ProcessLib::ParameterBase>>& parameters);
 
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_DIRICHLETBOUNDARYCONDITION_H
diff --git a/ProcessLib/BoundaryCondition/GenericNaturalBoundaryCondition.h b/ProcessLib/BoundaryCondition/GenericNaturalBoundaryCondition.h
index 5f2aeea6917..46be6d1232a 100644
--- a/ProcessLib/BoundaryCondition/GenericNaturalBoundaryCondition.h
+++ b/ProcessLib/BoundaryCondition/GenericNaturalBoundaryCondition.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_GENERICNATURALBOUNDARYCONDITION_H
-#define PROCESSLIB_GENERICNATURALBOUNDARYCONDITION_H
+#pragma once
 
 #include "MeshLib/MeshSubset.h"
 #include "BoundaryCondition.h"
@@ -74,5 +73,3 @@ private:
 }  // ProcessLib
 
 #include "GenericNaturalBoundaryCondition-impl.h"
-
-#endif  // PROCESSLIB_GENERICNATURALBOUNDARYCONDITION_H
diff --git a/ProcessLib/BoundaryCondition/GenericNaturalBoundaryConditionLocalAssembler.h b/ProcessLib/BoundaryCondition/GenericNaturalBoundaryConditionLocalAssembler.h
index d995288c107..6ce3e4423e3 100644
--- a/ProcessLib/BoundaryCondition/GenericNaturalBoundaryConditionLocalAssembler.h
+++ b/ProcessLib/BoundaryCondition/GenericNaturalBoundaryConditionLocalAssembler.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_GENERICNATURALBOUNDARYCONDITIONLOCALASSEMBLER_H
-#define PROCESSLIB_GENERICNATURALBOUNDARYCONDITIONLOCALASSEMBLER_H
+#pragma once
 
 #include "NumLib/Fem/ShapeMatrixPolicy.h"
 #include "ProcessLib/Utils/InitShapeMatrices.h"
@@ -53,5 +52,3 @@ protected:
 };
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_GENERICNATURALBOUNDARYCONDITIONLOCALASSEMBLER_H
diff --git a/ProcessLib/BoundaryCondition/NeumannBoundaryCondition.h b/ProcessLib/BoundaryCondition/NeumannBoundaryCondition.h
index 7f00d04e443..a0381cca18f 100644
--- a/ProcessLib/BoundaryCondition/NeumannBoundaryCondition.h
+++ b/ProcessLib/BoundaryCondition/NeumannBoundaryCondition.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_NEUMANNBOUNDARYCONDITION_H
-#define PROCESSLIB_NEUMANNBOUNDARYCONDITION_H
+#pragma once
 
 #include "ProcessLib/Parameter/Parameter.h"
 #include "GenericNaturalBoundaryCondition.h"
@@ -30,5 +29,3 @@ std::unique_ptr<NeumannBoundaryCondition> createNeumannBoundaryCondition(
     std::vector<std::unique_ptr<ParameterBase>> const& parameters);
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_NEUMANNBOUNDARYCONDITION_H
diff --git a/ProcessLib/BoundaryCondition/NeumannBoundaryConditionLocalAssembler.h b/ProcessLib/BoundaryCondition/NeumannBoundaryConditionLocalAssembler.h
index 1a58623c1c9..1a9b2c31b9a 100644
--- a/ProcessLib/BoundaryCondition/NeumannBoundaryConditionLocalAssembler.h
+++ b/ProcessLib/BoundaryCondition/NeumannBoundaryConditionLocalAssembler.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_NEUMANNBOUNDARYCONDITIONLOCALASSEMBLER_H
-#define PROCESSLIB_NEUMANNBOUNDARYCONDITIONLOCALASSEMBLER_H
+#pragma once
 
 #include "NumLib/DOF/DOFTableUtil.h"
 #include "ProcessLib/Parameter/Parameter.h"
@@ -73,5 +72,3 @@ private:
 };
 
 }   // namespace ProcessLib
-
-#endif  // PROCESSLIB_NEUMANNBOUNDARYCONDITIONLOCALASSEMBLER_H
diff --git a/ProcessLib/BoundaryCondition/RobinBoundaryCondition.h b/ProcessLib/BoundaryCondition/RobinBoundaryCondition.h
index fa989c37894..57cd2a415b1 100644
--- a/ProcessLib/BoundaryCondition/RobinBoundaryCondition.h
+++ b/ProcessLib/BoundaryCondition/RobinBoundaryCondition.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_ROBINBOUNDARYCONDITION_H
-#define PROCESSLIB_ROBINBOUNDARYCONDITION_H
+#pragma once
 
 #include "GenericNaturalBoundaryCondition.h"
 #include "RobinBoundaryConditionLocalAssembler.h"
@@ -46,5 +45,3 @@ std::unique_ptr<RobinBoundaryCondition> createRobinBoundaryCondition(
     std::vector<std::unique_ptr<ParameterBase>> const& parameters);
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_ROBINBOUNDARYCONDITION_H
diff --git a/ProcessLib/BoundaryCondition/RobinBoundaryConditionLocalAssembler.h b/ProcessLib/BoundaryCondition/RobinBoundaryConditionLocalAssembler.h
index e947e9245ed..44a1ceddefc 100644
--- a/ProcessLib/BoundaryCondition/RobinBoundaryConditionLocalAssembler.h
+++ b/ProcessLib/BoundaryCondition/RobinBoundaryConditionLocalAssembler.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_ROBINBOUNDARYCONDITIONLOCALASSEMBLER_H
-#define PROCESSLIB_ROBINBOUNDARYCONDITIONLOCALASSEMBLER_H
+#pragma once
 
 #include "NumLib/DOF/DOFTableUtil.h"
 #include "ProcessLib/Parameter/Parameter.h"
@@ -90,5 +89,3 @@ private:
 };
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_ROBINBOUNDARYCONDITIONLOCALASSEMBLER_H
diff --git a/ProcessLib/CachedSecondaryVariable.h b/ProcessLib/CachedSecondaryVariable.h
index 2129abb9f8c..3a8d3e790ce 100644
--- a/ProcessLib/CachedSecondaryVariable.h
+++ b/ProcessLib/CachedSecondaryVariable.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_CACHEDSECONDARYVARIABLE_H
-#define PROCESSLIB_CACHEDSECONDARYVARIABLE_H
+#pragma once
 
 #include "NumLib/Extrapolation/ExtrapolatableElementCollection.h"
 #include "NumLib/NamedFunctionProvider.h"
@@ -87,5 +86,3 @@ private:
 };
 
 }  // namespace ProcessLib
-
-#endif // PROCESSLIB_CACHEDSECONDARYVARIABLE_H
diff --git a/ProcessLib/CalculateSurfaceFlux/CalculateSurfaceFlux.h b/ProcessLib/CalculateSurfaceFlux/CalculateSurfaceFlux.h
index 1f6c75f4487..6bdbedb97de 100644
--- a/ProcessLib/CalculateSurfaceFlux/CalculateSurfaceFlux.h
+++ b/ProcessLib/CalculateSurfaceFlux/CalculateSurfaceFlux.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_CALCULATESURFACEFLUX_H_
-#define PROCESS_LIB_CALCULATESURFACEFLUX_H_
+#pragma once
 
 #include "ProcessLib/Process.h"
 #include "CalculateSurfaceFluxLocalAssembler.h"
@@ -43,5 +42,3 @@ private:
 };
 
 }   // namespace ProcessLib
-
-#endif  // PROCESS_LIB_CALCULATESURFACEFLUX_H_
diff --git a/ProcessLib/CalculateSurfaceFlux/CalculateSurfaceFluxLocalAssembler.h b/ProcessLib/CalculateSurfaceFlux/CalculateSurfaceFluxLocalAssembler.h
index 1764091d9b8..b5d863c6e57 100644
--- a/ProcessLib/CalculateSurfaceFlux/CalculateSurfaceFluxLocalAssembler.h
+++ b/ProcessLib/CalculateSurfaceFlux/CalculateSurfaceFluxLocalAssembler.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_CALCULATESURFACEFLUXLOCALASSEMBLER_H
-#define PROCESSLIB_CALCULATESURFACEFLUXLOCALASSEMBLER_H
+#pragma once
 
 #include "NumLib/Fem/ShapeMatrixPolicy.h"
 
@@ -156,5 +155,3 @@ private:
 };
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_CALCULATESURFACEFLUXLOCALASSEMBLER_H
diff --git a/ProcessLib/CalculateSurfaceFlux/MapBulkElementPoint.h b/ProcessLib/CalculateSurfaceFlux/MapBulkElementPoint.h
index 8a0c345dca7..2ecea0628a2 100644
--- a/ProcessLib/CalculateSurfaceFlux/MapBulkElementPoint.h
+++ b/ProcessLib/CalculateSurfaceFlux/MapBulkElementPoint.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_CALCULATESURFACEFLUX_MAPBULKELEMENT_H
-#define PROCESSLIB_CALCULATESURFACEFLUX_MAPBULKELEMENT_H
+#pragma once
 
 #include <array>
 
@@ -67,4 +66,3 @@ MathLib::Point3d getBulkElementPoint(MeshLib::Mesh const& mesh,
                                      std::size_t bulk_face_id,
                                      MathLib::WeightedPoint3D const& wp);
 }  // end namespace ProcessLib
-#endif
diff --git a/ProcessLib/CentralDifferencesJacobianAssembler.h b/ProcessLib/CentralDifferencesJacobianAssembler.h
index 45d9dabaf40..501d2a1a395 100644
--- a/ProcessLib/CentralDifferencesJacobianAssembler.h
+++ b/ProcessLib/CentralDifferencesJacobianAssembler.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_CENTRALDIFFERENCESJACOBIANASSEMBLER_H
-#define PROCESSLIB_CENTRALDIFFERENCESJACOBIANASSEMBLER_H
+#pragma once
 
 #include <memory>
 #include "AbstractJacobianAssembler.h"
@@ -72,5 +71,3 @@ std::unique_ptr<CentralDifferencesJacobianAssembler>
 createCentralDifferencesJacobianAssembler(BaseLib::ConfigTree const& config);
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_CENTRALDIFFERENCESJACOBIANASSEMBLER_H
diff --git a/ProcessLib/CreateJacobianAssembler.h b/ProcessLib/CreateJacobianAssembler.h
index 6927cb1e209..bf563ee3134 100644
--- a/ProcessLib/CreateJacobianAssembler.h
+++ b/ProcessLib/CreateJacobianAssembler.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_CREATEJACOBIANASSEMBLER_H
-#define PROCESSLIB_CREATEJACOBIANASSEMBLER_H
+#pragma once
 
 #include "BaseLib/ConfigTree.h"
 
@@ -19,5 +18,3 @@ class AbstractJacobianAssembler;
 std::unique_ptr<AbstractJacobianAssembler> createJacobianAssembler(
     boost::optional<BaseLib::ConfigTree> const& config);
 }  // ProcessLib
-
-#endif  // PROCESSLIB_CREATEJACOBIANASSEMBLER_H
diff --git a/ProcessLib/Deformation/BMatrixPolicy.h b/ProcessLib/Deformation/BMatrixPolicy.h
index 1b9bcb8e2eb..9b673877e87 100644
--- a/ProcessLib/Deformation/BMatrixPolicy.h
+++ b/ProcessLib/Deformation/BMatrixPolicy.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_FEM_BMATRIXPOLICY_H_
-#define PROCESSLIB_FEM_BMATRIXPOLICY_H_
+#pragma once
 
 #include "NumLib/Fem/ShapeMatrixPolicy.h"
 
@@ -94,5 +93,3 @@ public:
     using BMatrixType = MatrixType<_kelvin_vector_size, _number_of_dof>;
 };
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_FEM_BMATRIXPOLICY_H_
diff --git a/ProcessLib/Deformation/LinearBMatrix.h b/ProcessLib/Deformation/LinearBMatrix.h
index 9ba34f693da..1d122c9a142 100644
--- a/ProcessLib/Deformation/LinearBMatrix.h
+++ b/ProcessLib/Deformation/LinearBMatrix.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_FEM_DEFORMATION_LINEARBMATRIX_H_
-#define PROCESSLIB_FEM_DEFORMATION_LINEARBMATRIX_H_
+#pragma once
 
 #include <cmath>
 
@@ -78,5 +77,3 @@ void computeBMatrix(DNDX_Type const& dNdx,
 
 }  // namespace LinearBMatrix
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_FEM_DEFORMATION_LINEARBMATRIX_H_
diff --git a/ProcessLib/ExtrapolatorData.h b/ProcessLib/ExtrapolatorData.h
index 586a6e99468..a0e90dec9b8 100644
--- a/ProcessLib/ExtrapolatorData.h
+++ b/ProcessLib/ExtrapolatorData.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_EXTRAPOLATORDATA_H
-#define PROCESSLIB_EXTRAPOLATORDATA_H
+#pragma once
 
 #include <memory>
 #include "NumLib/DOF/LocalToGlobalIndexMap.h"
@@ -97,6 +96,3 @@ private:
 };
 
 } // namespace ProcessLib
-
-
-#endif // PROCESSLIB_EXTRAPOLATORDATA_H
diff --git a/ProcessLib/GlobalVectorFromNamedFunction.h b/ProcessLib/GlobalVectorFromNamedFunction.h
index 42a90e6a567..83ab3aa8e47 100644
--- a/ProcessLib/GlobalVectorFromNamedFunction.h
+++ b/ProcessLib/GlobalVectorFromNamedFunction.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_GLOBALVECTORFROMNAMEDFUNCTION_H
-#define PROCESSLIB_GLOBALVECTORFROMNAMEDFUNCTION_H
+#pragma once
 
 #include "MeshLib/Mesh.h"
 #include "NumLib/DOF/LocalToGlobalIndexMap.h"
@@ -54,5 +53,3 @@ private:
     SecondaryVariableContext& _context;
 };
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_GLOBALVECTORFROMNAMEDFUNCTION_H
diff --git a/ProcessLib/GroundwaterFlow/CreateGroundwaterFlowProcess.h b/ProcessLib/GroundwaterFlow/CreateGroundwaterFlowProcess.h
index 2e8b844d0a0..200124fb4eb 100644
--- a/ProcessLib/GroundwaterFlow/CreateGroundwaterFlowProcess.h
+++ b/ProcessLib/GroundwaterFlow/CreateGroundwaterFlowProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_CREATE_GROUNDWATERFLOWPROCESS_H_
-#define PROCESS_LIB_CREATE_GROUNDWATERFLOWPROCESS_H_
+#pragma once
 
 #include <memory>
 #include "ProcessLib/Process.h"
@@ -30,5 +29,3 @@ std::unique_ptr<Process> createGroundwaterFlowProcess(
 
 }   // namespace GroundwaterFlow
 }   // namespace ProcessLib
-
-#endif  // PROCESS_LIB_CREATE_GROUNDWATERFLOWPROCESS_H_
diff --git a/ProcessLib/GroundwaterFlow/GroundwaterFlowFEM.h b/ProcessLib/GroundwaterFlow/GroundwaterFlowFEM.h
index b3ed598fd73..029b46ba488 100644
--- a/ProcessLib/GroundwaterFlow/GroundwaterFlowFEM.h
+++ b/ProcessLib/GroundwaterFlow/GroundwaterFlowFEM.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_GROUNDWATERFLOW_FEM_H_
-#define PROCESS_LIB_GROUNDWATERFLOW_FEM_H_
+#pragma once
 
 #include <vector>
 
@@ -221,5 +220,3 @@ private:
 
 }  // namespace GroundwaterFlow
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_GROUNDWATERFLOW_FEM_H_
diff --git a/ProcessLib/GroundwaterFlow/GroundwaterFlowProcess.h b/ProcessLib/GroundwaterFlow/GroundwaterFlowProcess.h
index b6603b88ac4..f609740a863 100644
--- a/ProcessLib/GroundwaterFlow/GroundwaterFlowProcess.h
+++ b/ProcessLib/GroundwaterFlow/GroundwaterFlowProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_GROUNDWATERFLOWPROCESS_H_
-#define PROCESS_LIB_GROUNDWATERFLOWPROCESS_H_
+#pragma once
 
 #include "NumLib/DOF/LocalToGlobalIndexMap.h"
 #include "ProcessLib/Process.h"
@@ -118,5 +117,3 @@ private:
 
 }   // namespace GroundwaterFlow
 }   // namespace ProcessLib
-
-#endif  // PROCESS_LIB_GROUNDWATERFLOWPROCESS_H_
diff --git a/ProcessLib/GroundwaterFlow/GroundwaterFlowProcessData.h b/ProcessLib/GroundwaterFlow/GroundwaterFlowProcessData.h
index 28e668c8b0a..9218c2f5987 100644
--- a/ProcessLib/GroundwaterFlow/GroundwaterFlowProcessData.h
+++ b/ProcessLib/GroundwaterFlow/GroundwaterFlowProcessData.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_GROUNDWATERFLOW_GROUNDWATERFLOWPROCESSDATA_H
-#define PROCESSLIB_GROUNDWATERFLOW_GROUNDWATERFLOWPROCESSDATA_H
+#pragma once
 
 namespace MeshLib
 {
@@ -50,5 +49,3 @@ struct GroundwaterFlowProcessData
 
 } // namespace GroundwaterFlow
 } // namespace ProcessLib
-
-#endif // PROCESSLIB_GROUNDWATERFLOW_GROUNDWATERFLOWPROCESSDATA_H
diff --git a/ProcessLib/HT/CreateHTProcess.h b/ProcessLib/HT/CreateHTProcess.h
index d7b8f6ec094..fb71e3df282 100644
--- a/ProcessLib/HT/CreateHTProcess.h
+++ b/ProcessLib/HT/CreateHTProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_CREATE_HTPROCESS_H_
-#define PROCESS_LIB_CREATE_HTPROCESS_H_
+#pragma once
 
 #include <memory>
 #include "ProcessLib/Process.h"
@@ -27,5 +26,3 @@ std::unique_ptr<Process> createHTProcess(
 
 }  // namespace HT
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_CREATE_HTPROCESS_H_
diff --git a/ProcessLib/HT/HTFEM.h b/ProcessLib/HT/HTFEM.h
index a0598e1b3ef..297873c7c76 100644
--- a/ProcessLib/HT/HTFEM.h
+++ b/ProcessLib/HT/HTFEM.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_HTPROCESS_FEM_H_
-#define PROCESS_LIB_HTPROCESS_FEM_H_
+#pragma once
 
 #include <iostream>
 #include <Eigen/Dense>
@@ -261,5 +260,3 @@ private:
 
 }  // namespace HT
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_HT_FEM_H_
diff --git a/ProcessLib/HT/HTProcess.h b/ProcessLib/HT/HTProcess.h
index 5e73ad3f3bc..355dba18b5b 100644
--- a/ProcessLib/HT/HTProcess.h
+++ b/ProcessLib/HT/HTProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_HTPROCESS_H_
-#define PROCESS_LIB_HTPROCESS_H_
+#pragma once
 
 #include "HTFEM.h"
 #include "HTProcessData.h"
@@ -80,5 +79,3 @@ private:
 
 }  // namespace HT
 }  // namespace ProcessLib
-
-#endif // PROCESS_LIB_HTPROCESS_H_
diff --git a/ProcessLib/HT/HTProcessData.h b/ProcessLib/HT/HTProcessData.h
index 1b5968e12ae..b32e65184c2 100644
--- a/ProcessLib/HT/HTProcessData.h
+++ b/ProcessLib/HT/HTProcessData.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_HT_HTPROCESSDATA_H
-#define PROCESSLIB_HT_HTPROCESSDATA_H
+#pragma once
 
 namespace MeshLib
 {
@@ -112,5 +111,3 @@ struct HTProcessData
 
 }  // namespace HT
 }  // namespace ProcessLib
-
-#endif // PROCESSLIB_HT_HTPROCESSDATA_H
diff --git a/ProcessLib/HeatConduction/CreateHeatConductionProcess.h b/ProcessLib/HeatConduction/CreateHeatConductionProcess.h
index 9ce980f2e9a..cb529e930dc 100644
--- a/ProcessLib/HeatConduction/CreateHeatConductionProcess.h
+++ b/ProcessLib/HeatConduction/CreateHeatConductionProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_CREATE_HEATCONDUCTIONPROCESS_H_
-#define PROCESS_LIB_CREATE_HEATCONDUCTIONPROCESS_H_
+#pragma once
 
 #include <memory>
 #include "ProcessLib/Process.h"
@@ -27,5 +26,3 @@ std::unique_ptr<Process> createHeatConductionProcess(
 
 }  // namespace HeatConduction
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_CREATE_HEATCONDUCTIONPROCESS_H_
diff --git a/ProcessLib/HeatConduction/HeatConductionFEM.h b/ProcessLib/HeatConduction/HeatConductionFEM.h
index fb33be2eb61..1380762dd27 100644
--- a/ProcessLib/HeatConduction/HeatConductionFEM.h
+++ b/ProcessLib/HeatConduction/HeatConductionFEM.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_HEATCONDUCTION_FEM_H_
-#define PROCESS_LIB_HEATCONDUCTION_FEM_H_
+#pragma once
 
 #include <vector>
 
@@ -193,5 +192,3 @@ private:
 
 }  // namespace HeatConduction
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_HEATCONDUCTION_FEM_H_
diff --git a/ProcessLib/HeatConduction/HeatConductionProcess.h b/ProcessLib/HeatConduction/HeatConductionProcess.h
index dc5046aa6f5..dd2c340e1b0 100644
--- a/ProcessLib/HeatConduction/HeatConductionProcess.h
+++ b/ProcessLib/HeatConduction/HeatConductionProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_HEATCONDUCTIONPROCESS_H_
-#define PROCESS_LIB_HEATCONDUCTIONPROCESS_H_
+#pragma once
 
 #include "ProcessLib/Process.h"
 #include "HeatConductionFEM.h"
@@ -65,5 +64,3 @@ private:
 
 }  // namespace HeatConduction
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_HEATCONDUCTIONPROCESS_H_
diff --git a/ProcessLib/HeatConduction/HeatConductionProcessData.h b/ProcessLib/HeatConduction/HeatConductionProcessData.h
index 124401a555e..06d72977862 100644
--- a/ProcessLib/HeatConduction/HeatConductionProcessData.h
+++ b/ProcessLib/HeatConduction/HeatConductionProcessData.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_HEATCONDUCTION_HEATCONDUCTIONPROCESSDATA_H
-#define PROCESSLIB_HEATCONDUCTION_HEATCONDUCTIONPROCESSDATA_H
+#pragma once
 
 namespace MeshLib
 {
@@ -57,5 +56,3 @@ struct HeatConductionProcessData
 
 }  // namespace HeatConduction
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_HEATCONDUCTION_HEATCONDUCTIONPROCESSDATA_H
diff --git a/ProcessLib/HydroMechanics/CreateHydroMechanicsProcess.h b/ProcessLib/HydroMechanics/CreateHydroMechanicsProcess.h
index 4f5c7136bb0..bf68fcf2275 100644
--- a/ProcessLib/HydroMechanics/CreateHydroMechanicsProcess.h
+++ b/ProcessLib/HydroMechanics/CreateHydroMechanicsProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_CREATEHYDROMECHANICSPROCESS_H_
-#define PROCESS_LIB_CREATEHYDROMECHANICSPROCESS_H_
+#pragma once
 
 #include "ProcessLib/Process.h"
 
@@ -27,5 +26,3 @@ std::unique_ptr<Process> createHydroMechanicsProcess(
 
 }  // namespace HydroMechanics
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_CREATEHYDROMECHANICSPROCESS_H_
diff --git a/ProcessLib/HydroMechanics/CreateLocalAssemblers.h b/ProcessLib/HydroMechanics/CreateLocalAssemblers.h
index 4e34e7584d8..305e5744269 100644
--- a/ProcessLib/HydroMechanics/CreateLocalAssemblers.h
+++ b/ProcessLib/HydroMechanics/CreateLocalAssemblers.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef PROCESSLIB_HYDROMECHANICS_CREATE_LOCAL_ASSEMBLERS_H_
-#define PROCESSLIB_HYDROMECHANICS_CREATE_LOCAL_ASSEMBLERS_H_
+#pragma once
 
 #include <vector>
 
@@ -101,5 +100,3 @@ void createLocalAssemblers(
 }  // HydroMechanics
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_HYDROMECHANICS_CREATE_LOCAL_ASSEMBLERS_H_
diff --git a/ProcessLib/HydroMechanics/HydroMechanicsFEM.h b/ProcessLib/HydroMechanics/HydroMechanicsFEM.h
index e4a63ceceac..c39a47baf5d 100644
--- a/ProcessLib/HydroMechanics/HydroMechanicsFEM.h
+++ b/ProcessLib/HydroMechanics/HydroMechanicsFEM.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_HYDROMECHANICS_FEM_H_
-#define PROCESS_LIB_HYDROMECHANICS_FEM_H_
+#pragma once
 
 #include <iostream>
 #include <memory>
@@ -402,5 +401,3 @@ public:
 
 }  // namespace HydroMechanics
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_HYDROMECHANICS_FEM_H_
diff --git a/ProcessLib/HydroMechanics/HydroMechanicsProcess-fwd.h b/ProcessLib/HydroMechanics/HydroMechanicsProcess-fwd.h
index de0adc0afa0..c0a54772a7b 100644
--- a/ProcessLib/HydroMechanics/HydroMechanicsProcess-fwd.h
+++ b/ProcessLib/HydroMechanics/HydroMechanicsProcess-fwd.h
@@ -7,12 +7,9 @@
  *
  */
 
-#ifndef PROCESS_LIB_HYDROMECHANICSPROCESS_FWD_H_
-#define PROCESS_LIB_HYDROMECHANICSPROCESS_FWD_H_
+#pragma once
 
 #include "HydroMechanicsProcess.h"
 
 extern template class ProcessLib::HydroMechanics::HydroMechanicsProcess<2>;
 extern template class ProcessLib::HydroMechanics::HydroMechanicsProcess<3>;
-
-#endif  // PROCESS_LIB_HYDROMECHANICSPROCESS_FWD_H_
diff --git a/ProcessLib/HydroMechanics/HydroMechanicsProcess.h b/ProcessLib/HydroMechanics/HydroMechanicsProcess.h
index d219b8c1009..3087dfb382a 100644
--- a/ProcessLib/HydroMechanics/HydroMechanicsProcess.h
+++ b/ProcessLib/HydroMechanics/HydroMechanicsProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_HYDROMECHANICSPROCESS_H_
-#define PROCESS_LIB_HYDROMECHANICSPROCESS_H_
+#pragma once
 
 #include <cassert>
 
@@ -163,5 +162,3 @@ private:
 
 }  // namespace HydroMechanics
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_HYDROMECHANICSPROCESS_H_
diff --git a/ProcessLib/HydroMechanics/HydroMechanicsProcessData.h b/ProcessLib/HydroMechanics/HydroMechanicsProcessData.h
index 7e2b6dba3da..1172958b3af 100644
--- a/ProcessLib/HydroMechanics/HydroMechanicsProcessData.h
+++ b/ProcessLib/HydroMechanics/HydroMechanicsProcessData.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_HYDROMECHANICS_HYDROMECHANICSPROCESSDATA_H_
-#define PROCESSLIB_HYDROMECHANICS_HYDROMECHANICSPROCESSDATA_H_
+#pragma once
 
 #include <Eigen/Dense>
 
@@ -100,5 +99,3 @@ struct HydroMechanicsProcessData
 
 }  // namespace HydroMechanics
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_HYDROMECHANICS_HYDROMECHANICSPROCESSDATA_H_
diff --git a/ProcessLib/HydroMechanics/LocalDataInitializer.h b/ProcessLib/HydroMechanics/LocalDataInitializer.h
index afaf2db2afb..2869c4cd017 100644
--- a/ProcessLib/HydroMechanics/LocalDataInitializer.h
+++ b/ProcessLib/HydroMechanics/LocalDataInitializer.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_HYDROMECHANICS_LOCALDATAINITIALIZER_H_
-#define PROCESSLIB_HYDROMECHANICS_LOCALDATAINITIALIZER_H_
+#pragma once
 
 #include <functional>
 #include <memory>
@@ -289,5 +288,3 @@ private:
 #undef ENABLED_ELEMENT_TYPE_TRI
 #undef ENABLED_ELEMENT_TYPE_QUAD
 #undef OGS_ENABLED_ELEMENTS
-
-#endif  // PROCESSLIB_HYDROMECHANICS_LOCALDATAINITIALIZER_H_
diff --git a/ProcessLib/LIE/BoundaryCondition/BoundaryConditionBuilder.h b/ProcessLib/LIE/BoundaryCondition/BoundaryConditionBuilder.h
index 8fb3cebe87c..d4276b253f1 100644
--- a/ProcessLib/LIE/BoundaryCondition/BoundaryConditionBuilder.h
+++ b/ProcessLib/LIE/BoundaryCondition/BoundaryConditionBuilder.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_BOUNDARYCONDITIONBUILDER_H_
-#define PROCESSLIB_LIE_BOUNDARYCONDITIONBUILDER_H_
+#pragma once
 
 #include "NumLib/NumericsConfig.h"
 
@@ -56,5 +55,3 @@ private:
 
 }  // LIE
 }  // ProcessLib
-
-#endif // PROCESSLIB_LIE_BOUNDARYCONDITIONBUILDER_H_
diff --git a/ProcessLib/LIE/BoundaryCondition/GenericNaturalBoundaryCondition-impl.h b/ProcessLib/LIE/BoundaryCondition/GenericNaturalBoundaryCondition-impl.h
index c2f2e4044cf..7fe1d52b7c7 100644
--- a/ProcessLib/LIE/BoundaryCondition/GenericNaturalBoundaryCondition-impl.h
+++ b/ProcessLib/LIE/BoundaryCondition/GenericNaturalBoundaryCondition-impl.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_GENERICNATURALBOUNDARYCONDITION_IMPL_H_
-#define PROCESSLIB_LIE_GENERICNATURALBOUNDARYCONDITION_IMPL_H_
+#pragma once
 
 #include "GenericNaturalBoundaryCondition.h"
 
@@ -98,5 +97,3 @@ void GenericNaturalBoundaryCondition<
 
 }  // LIE
 }  // ProcessLib
-
-#endif // PROCESSLIB_LIE_GENERICNATURALBOUNDARYCONDITION_IMPL_H_
diff --git a/ProcessLib/LIE/BoundaryCondition/GenericNaturalBoundaryCondition.h b/ProcessLib/LIE/BoundaryCondition/GenericNaturalBoundaryCondition.h
index 5a808a57040..2f856a85a7e 100644
--- a/ProcessLib/LIE/BoundaryCondition/GenericNaturalBoundaryCondition.h
+++ b/ProcessLib/LIE/BoundaryCondition/GenericNaturalBoundaryCondition.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_GENERICNATURALBOUNDARYCONDITION_H_
-#define PROCESSLIB_LIE_GENERICNATURALBOUNDARYCONDITION_H_
+#pragma once
 
 #include "MeshLib/MeshSubset.h"
 #include "ProcessLib/BoundaryCondition/BoundaryCondition.h"
@@ -80,5 +79,3 @@ private:
 }  // ProcessLib
 
 #include "GenericNaturalBoundaryCondition-impl.h"
-
-#endif // PROCESSLIB_LIE_GENERICNATURALBOUNDARYCONDITION_H_
diff --git a/ProcessLib/LIE/BoundaryCondition/NeumannBoundaryCondition.h b/ProcessLib/LIE/BoundaryCondition/NeumannBoundaryCondition.h
index 3bf1e8c0efe..c3fddf08c0d 100644
--- a/ProcessLib/LIE/BoundaryCondition/NeumannBoundaryCondition.h
+++ b/ProcessLib/LIE/BoundaryCondition/NeumannBoundaryCondition.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_NEUMANNBOUNDARYCONDITION_H_
-#define PROCESSLIB_LIE_NEUMANNBOUNDARYCONDITION_H_
+#pragma once
 
 #include "ProcessLib/Parameter/Parameter.h"
 #include "ProcessLib/BoundaryCondition/BoundaryCondition.h"
@@ -40,5 +39,3 @@ createNeumannBoundaryCondition(
 
 }  // LIE
 }  // ProcessLib
-
-#endif // PROCESSLIB_LIE_NEUMANNBOUNDARYCONDITION_H_
diff --git a/ProcessLib/LIE/BoundaryCondition/NeumannBoundaryConditionLocalAssembler.h b/ProcessLib/LIE/BoundaryCondition/NeumannBoundaryConditionLocalAssembler.h
index 948bbe22f0b..3eff9000f02 100644
--- a/ProcessLib/LIE/BoundaryCondition/NeumannBoundaryConditionLocalAssembler.h
+++ b/ProcessLib/LIE/BoundaryCondition/NeumannBoundaryConditionLocalAssembler.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_NEUMANNBOUNDARYCONDITION_LOCALASSEMBLER_H_
-#define PROCESSLIB_LIE_NEUMANNBOUNDARYCONDITION_LOCALASSEMBLER_H_
+#pragma once
 
 #include "NumLib/DOF/DOFTableUtil.h"
 
@@ -94,5 +93,3 @@ private:
 
 }   // namespace LIE
 }   // namespace ProcessLib
-
-#endif // PROCESSLIB_LIE_NEUMANNBOUNDARYCONDITION_LOCALASSEMBLER_H_
diff --git a/ProcessLib/LIE/Common/FractureProperty.h b/ProcessLib/LIE/Common/FractureProperty.h
index 25414f6514f..66343232784 100644
--- a/ProcessLib/LIE/Common/FractureProperty.h
+++ b/ProcessLib/LIE/Common/FractureProperty.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_COMMON_FRACTUREPROPERTY_H_
-#define PROCESSLIB_LIE_COMMON_FRACTUREPROPERTY_H_
+#pragma once
 
 #include <Eigen/Eigen>
 
@@ -55,5 +54,3 @@ inline void setFractureProperty(unsigned dim, MeshLib::Element const& e,
 
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif // PROCESSLIB_LIE_COMMON_FRACTUREPROPERTY_H_
diff --git a/ProcessLib/LIE/Common/HMatrixUtils.h b/ProcessLib/LIE/Common/HMatrixUtils.h
index c7780ee72e2..6a80b9600d1 100644
--- a/ProcessLib/LIE/Common/HMatrixUtils.h
+++ b/ProcessLib/LIE/Common/HMatrixUtils.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_COMMON_HMATRIXPOLICYTYPE_H_
-#define PROCESSLIB_LIE_COMMON_HMATRIXPOLICYTYPE_H_
+#pragma once
 
 #include "NumLib/Fem/ShapeMatrixPolicy.h"
 
@@ -62,5 +61,3 @@ void computeHMatrix(N_Type const& N, HMatrixType& H)
 }
 
 }  // namespace ProcessLib
-
-#endif // PROCESSLIB_LIE_COMMON_HMATRIXPOLICYTYPE_H_
diff --git a/ProcessLib/LIE/Common/LevelSetFunction.h b/ProcessLib/LIE/Common/LevelSetFunction.h
index e663268cea2..e373103a22c 100644
--- a/ProcessLib/LIE/Common/LevelSetFunction.h
+++ b/ProcessLib/LIE/Common/LevelSetFunction.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef PROCESSLIB_LIE_COMMON_LEVELSETFUNCTION_H_
-#define PROCESSLIB_LIE_COMMON_LEVELSETFUNCTION_H_
+#pragma once
 
 namespace ProcessLib
 {
@@ -25,5 +24,3 @@ double calculateLevelSetFunction(
 
 } // LIE
 } // ProcessLib
-
-#endif // PROCESSLIB_LIE_COMMON_LEVELSETFUNCTION_H_
diff --git a/ProcessLib/LIE/Common/MeshUtils.h b/ProcessLib/LIE/Common/MeshUtils.h
index ab4588f5f6a..a3235bd4853 100644
--- a/ProcessLib/LIE/Common/MeshUtils.h
+++ b/ProcessLib/LIE/Common/MeshUtils.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef PROCESSLIB_LIE_COMMON_MESHUTILS_H_
-#define PROCESSLIB_LIE_COMMON_MESHUTILS_H_
+#pragma once
 
 #include <vector>
 
@@ -43,5 +42,3 @@ void getFractureMatrixDataInMesh(
 
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif // PROCESSLIB_LIE_COMMON_MESHUTILS_H_
diff --git a/ProcessLib/LIE/Common/PostUtils.h b/ProcessLib/LIE/Common/PostUtils.h
index 1f57aba72cd..2492cd0efe1 100644
--- a/ProcessLib/LIE/Common/PostUtils.h
+++ b/ProcessLib/LIE/Common/PostUtils.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef PROCESSLIB_LIE_COMMON_POSTUTILS_H_
-#define PROCESSLIB_LIE_COMMON_POSTUTILS_H_
+#pragma once
 
 #include <map>
 #include <memory>
@@ -48,5 +47,3 @@ private:
 
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif // PROCESSLIB_LIE_COMMON_POSTUTILS_H_
diff --git a/ProcessLib/LIE/Common/Utils.h b/ProcessLib/LIE/Common/Utils.h
index f8e9a98f92d..8b23708cc16 100644
--- a/ProcessLib/LIE/Common/Utils.h
+++ b/ProcessLib/LIE/Common/Utils.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef PROCESSLIB_LIE_COMMON_UTILS_H_
-#define PROCESSLIB_LIE_COMMON_UTILS_H_
+#pragma once
 
 #include <Eigen/Eigen>
 
@@ -41,5 +40,3 @@ MathLib::Point3d computePhysicalCoordinates(MeshLib::Element const&e, Eigen::Mat
 
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif
diff --git a/ProcessLib/LIE/HydroMechanics/CreateHydroMechanicsProcess.h b/ProcessLib/LIE/HydroMechanics/CreateHydroMechanicsProcess.h
index 74c9b98a221..28657054ee0 100644
--- a/ProcessLib/LIE/HydroMechanics/CreateHydroMechanicsProcess.h
+++ b/ProcessLib/LIE/HydroMechanics/CreateHydroMechanicsProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_LIE_CREATEHYDROMECHANICSPROCESS_H_
-#define PROCESS_LIB_LIE_CREATEHYDROMECHANICSPROCESS_H_
+#pragma once
 
 #include <memory>
 #include <vector>
@@ -33,5 +32,3 @@ std::unique_ptr<Process> createHydroMechanicsProcess(
 }  // namespace HydroMechanics
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_LIE_CREATEHYDROMECHANICSPROCESS_H_
diff --git a/ProcessLib/LIE/HydroMechanics/HydroMechanicsProcess-fwd.h b/ProcessLib/LIE/HydroMechanics/HydroMechanicsProcess-fwd.h
index adb84609b39..340890b30af 100644
--- a/ProcessLib/LIE/HydroMechanics/HydroMechanicsProcess-fwd.h
+++ b/ProcessLib/LIE/HydroMechanics/HydroMechanicsProcess-fwd.h
@@ -7,11 +7,8 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_HYDROMECHANICSPROCESS_FWD_H_
-#define PROCESSLIB_LIE_HYDROMECHANICSPROCESS_FWD_H_
+#pragma once
 
 #include "HydroMechanicsProcess.h"
 
 extern template class ProcessLib::LIE::HydroMechanics::HydroMechanicsProcess<2>;
-
-#endif  // PROCESSLIB_LIE_HYDROMECHANICSPROCESS_FWD_H_
diff --git a/ProcessLib/LIE/HydroMechanics/HydroMechanicsProcess.h b/ProcessLib/LIE/HydroMechanics/HydroMechanicsProcess.h
index f697820f87d..1c21e10699a 100644
--- a/ProcessLib/LIE/HydroMechanics/HydroMechanicsProcess.h
+++ b/ProcessLib/LIE/HydroMechanics/HydroMechanicsProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_HYDROMECHANICS_PROCESS_H_
-#define PROCESSLIB_LIE_HYDROMECHANICS_PROCESS_H_
+#pragma once
 
 #include <cassert>
 
@@ -125,5 +124,3 @@ private:
 }  // namespace HydroMechanics
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_LIE_HYDROMECHANICS_PROCESS_H_
diff --git a/ProcessLib/LIE/HydroMechanics/HydroMechanicsProcessData.h b/ProcessLib/LIE/HydroMechanics/HydroMechanicsProcessData.h
index f09ff3163b6..920a9780727 100644
--- a/ProcessLib/LIE/HydroMechanics/HydroMechanicsProcessData.h
+++ b/ProcessLib/LIE/HydroMechanics/HydroMechanicsProcessData.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSPROCESSDATA_H_
-#define PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSPROCESSDATA_H_
+#pragma once
 
 #include <memory>
 #include <Eigen/Dense>
@@ -144,5 +143,3 @@ struct HydroMechanicsProcessData
 }  // namespace HydroMechanics
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSPROCESSDATA_H_
diff --git a/ProcessLib/LIE/HydroMechanics/LocalAssembler/CreateLocalAssemblers.h b/ProcessLib/LIE/HydroMechanics/LocalAssembler/CreateLocalAssemblers.h
index 8eef1a4f2c8..f1a98097d80 100644
--- a/ProcessLib/LIE/HydroMechanics/LocalAssembler/CreateLocalAssemblers.h
+++ b/ProcessLib/LIE/HydroMechanics/LocalAssembler/CreateLocalAssemblers.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef PROCESSLIB_LIE_HYDROMECHANICS_CREATE_LOCAL_ASSEMBLERS_H_
-#define PROCESSLIB_LIE_HYDROMECHANICS_CREATE_LOCAL_ASSEMBLERS_H_
+#pragma once
 
 #include <vector>
 
@@ -99,5 +98,3 @@ void createLocalAssemblers(
 }  // namespace HydroMechanics
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_LIE_HYDROMECHANICS_CREATE_LOCAL_ASSEMBLERS_H_
diff --git a/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerFracture-impl.h b/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerFracture-impl.h
index 2082ac54ed4..d016533b04c 100644
--- a/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerFracture-impl.h
+++ b/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerFracture-impl.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_FRACTURE_IMPL_H_
-#define PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_FRACTURE_IMPL_H_
+#pragma once
 
 #include "HydroMechanicsLocalAssemblerFracture.h"
 
@@ -394,5 +393,3 @@ computeSecondaryVariableConcreteWithVector(
 }  // namespace HydroMechanics
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_FRACTURE_IMPL_H_
diff --git a/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerFracture.h b/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerFracture.h
index c45a144eeb0..2baab2ac940 100644
--- a/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerFracture.h
+++ b/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerFracture.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_FRACTURE_H_
-#define PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_FRACTURE_H_
+#pragma once
 
 #include <vector>
 
@@ -118,5 +117,3 @@ private:
 }  // namespace ProcessLib
 
 #include "HydroMechanicsLocalAssemblerFracture-impl.h"
-
-#endif  // PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_FRACTURE_H_
diff --git a/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerInterface.h b/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerInterface.h
index dd96b2cc835..f30d8385a44 100644
--- a/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerInterface.h
+++ b/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerInterface.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLERINTERFACE_H_
-#define PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLERINTERFACE_H_
+#pragma once
 
 #include <vector>
 
@@ -127,5 +126,3 @@ private:
 }  // namespace HydroMechanics
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLERINTERFACE_H_
diff --git a/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerMatrix-impl.h b/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerMatrix-impl.h
index e5bf3568fcf..de3dc8d5833 100644
--- a/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerMatrix-impl.h
+++ b/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerMatrix-impl.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_MATRIX_IMPL_H_
-#define PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_MATRIX_IMPL_H_
+#pragma once
 
 #include "HydroMechanicsLocalAssemblerMatrix.h"
 
@@ -420,5 +419,3 @@ setPressureDotOfInactiveNodes(Eigen::Ref<Eigen::VectorXd> p_dot)
 }  // namespace HydroMechanics
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_MATRIX_IMPL_H_
diff --git a/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerMatrix.h b/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerMatrix.h
index 9240c56d83b..6538d4da9c2 100644
--- a/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerMatrix.h
+++ b/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerMatrix.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_MATRIX_H_
-#define PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_MATRIX_H_
+#pragma once
 
 #include <vector>
 
@@ -130,5 +129,3 @@ protected:
 }  // namespace ProcessLib
 
 #include "HydroMechanicsLocalAssemblerMatrix-impl.h"
-
-#endif  // PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_MATRIX_H_
diff --git a/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerMatrixNearFracture-impl.h b/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerMatrixNearFracture-impl.h
index 33c2561a426..d9c1528bd38 100644
--- a/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerMatrixNearFracture-impl.h
+++ b/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerMatrixNearFracture-impl.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_MATRIX_NEAR_FRACTUER_IMPL_H_
-#define PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_MATRIX_NEAR_FRACTUER_IMPL_H_
+#pragma once
 
 #include "HydroMechanicsLocalAssemblerMatrixNearFracture.h"
 
@@ -165,5 +164,3 @@ computeSecondaryVariableConcreteWithVector(
 }  // namespace HydroMechanics
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif // PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_MATRIX_NEAR_FRACTUER_IMPL_H_
diff --git a/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerMatrixNearFracture.h b/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerMatrixNearFracture.h
index 94f7faff395..45d61e9c04e 100644
--- a/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerMatrixNearFracture.h
+++ b/ProcessLib/LIE/HydroMechanics/LocalAssembler/HydroMechanicsLocalAssemblerMatrixNearFracture.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_MATRIX_NEAR_FRACTUER_H_
-#define PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_MATRIX_NEAR_FRACTUER_H_
+#pragma once
 
 #include <vector>
 
@@ -80,5 +79,3 @@ private:
 }  // namespace ProcessLib
 
 #include "HydroMechanicsLocalAssemblerMatrixNearFracture-impl.h"
-
-#endif // PROCESSLIB_LIE_HYDROMECHANICS_HYDROMECHANICSLOCALASSEMBLER_MATRIX_H_
diff --git a/ProcessLib/LIE/HydroMechanics/LocalAssembler/IntegrationPointDataFracture.h b/ProcessLib/LIE/HydroMechanics/LocalAssembler/IntegrationPointDataFracture.h
index e1c7cd00f0b..9bab78f2790 100644
--- a/ProcessLib/LIE/HydroMechanics/LocalAssembler/IntegrationPointDataFracture.h
+++ b/ProcessLib/LIE/HydroMechanics/LocalAssembler/IntegrationPointDataFracture.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_HYDROMECHANICS_INTEGRATIONPOINTDATAFRACTURE_H_
-#define PROCESSLIB_LIE_HYDROMECHANICS_INTEGRATIONPOINTDATAFRACTURE_H_
+#pragma once
 
 #include <Eigen/Eigen>
 
@@ -80,5 +79,3 @@ struct IntegrationPointDataFracture final
 }  // namespace HydroMechanics
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif // PROCESSLIB_LIE_HYDROMECHANICS_INTEGRATIONPOINTDATAFRACTURE_H_
diff --git a/ProcessLib/LIE/HydroMechanics/LocalAssembler/IntegrationPointDataMatrix.h b/ProcessLib/LIE/HydroMechanics/LocalAssembler/IntegrationPointDataMatrix.h
index b8bd657ba27..dc873c00b9a 100644
--- a/ProcessLib/LIE/HydroMechanics/LocalAssembler/IntegrationPointDataMatrix.h
+++ b/ProcessLib/LIE/HydroMechanics/LocalAssembler/IntegrationPointDataMatrix.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_HYDROMECHANICS_INTEGRATIONPOINTDATAMATRIX_H_
-#define PROCESSLIB_LIE_HYDROMECHANICS_INTEGRATIONPOINTDATAMATRIX_H_
+#pragma once
 
 #include <memory>
 #include <vector>
@@ -85,5 +84,3 @@ struct IntegrationPointDataMatrix final
 }  // namespace HydroMechanics
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif // PROCESSLIB_LIE_HYDROMECHANICS_INTEGRATIONPOINTDATAMATRIX_H_
diff --git a/ProcessLib/LIE/HydroMechanics/LocalAssembler/LocalDataInitializer.h b/ProcessLib/LIE/HydroMechanics/LocalAssembler/LocalDataInitializer.h
index b6989930870..29f2dc6223f 100644
--- a/ProcessLib/LIE/HydroMechanics/LocalAssembler/LocalDataInitializer.h
+++ b/ProcessLib/LIE/HydroMechanics/LocalAssembler/LocalDataInitializer.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_HYDROMECHANICS_LOCALDATAINITIALIZER_H_
-#define PROCESSLIB_LIE_HYDROMECHANICS_LOCALDATAINITIALIZER_H_
+#pragma once
 
 #include <functional>
 #include <memory>
@@ -356,5 +355,3 @@ private:
 #undef ENABLED_ELEMENT_TYPE_TRI
 #undef ENABLED_ELEMENT_TYPE_QUAD
 #undef OGS_ENABLED_ELEMENTS
-
-#endif  // PROCESSLIB_LIE_HYDROMECHANICS_LOCALDATAINITIALIZER_H_
diff --git a/ProcessLib/LIE/SmallDeformation/CreateSmallDeformationProcess.h b/ProcessLib/LIE/SmallDeformation/CreateSmallDeformationProcess.h
index 7d0c911a655..1247859c1cc 100644
--- a/ProcessLib/LIE/SmallDeformation/CreateSmallDeformationProcess.h
+++ b/ProcessLib/LIE/SmallDeformation/CreateSmallDeformationProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_CREATESMALLDEFORMATIONPROCESS_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_CREATESMALLDEFORMATIONPROCESS_H_
+#pragma once
 
 #include <memory>
 #include <vector>
@@ -34,5 +33,3 @@ std::unique_ptr<Process> createSmallDeformationProcess(
 }  // namespace SmallDeformation
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_LIE_SMALLDEFORMATION_CREATESMALLDEFORMATIONPROCESS_H_
diff --git a/ProcessLib/LIE/SmallDeformation/LocalAssembler/CreateLocalAssemblers.h b/ProcessLib/LIE/SmallDeformation/LocalAssembler/CreateLocalAssemblers.h
index e3e1f10698f..5ecb452f78b 100644
--- a/ProcessLib/LIE/SmallDeformation/LocalAssembler/CreateLocalAssemblers.h
+++ b/ProcessLib/LIE/SmallDeformation/LocalAssembler/CreateLocalAssemblers.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_CREATE_LOCAL_ASSEMBLERS_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_CREATE_LOCAL_ASSEMBLERS_H_
+#pragma once
 
 #include <vector>
 
@@ -113,5 +112,3 @@ void createLocalAssemblers(
 }  // namespace SmallDeformation
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_LIE_SMALLDEFORMATION_CREATE_LOCAL_ASSEMBLERS_H_
diff --git a/ProcessLib/LIE/SmallDeformation/LocalAssembler/IntegrationPointDataFracture.h b/ProcessLib/LIE/SmallDeformation/LocalAssembler/IntegrationPointDataFracture.h
index 65fc233831d..ce84d4edfc2 100644
--- a/ProcessLib/LIE/SmallDeformation/LocalAssembler/IntegrationPointDataFracture.h
+++ b/ProcessLib/LIE/SmallDeformation/LocalAssembler/IntegrationPointDataFracture.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_INTEGRATIONPOINTDATAFRACTURE_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_INTEGRATIONPOINTDATAFRACTURE_H_
+#pragma once
 
 #include <Eigen/Eigen>
 
@@ -78,5 +77,3 @@ struct IntegrationPointDataFracture final
 }  // namespace SmallDeformation
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif // PROCESSLIB_LIE_SMALLDEFORMATION_INTEGRATIONPOINTDATAFRACTURE_H_
diff --git a/ProcessLib/LIE/SmallDeformation/LocalAssembler/IntegrationPointDataMatrix.h b/ProcessLib/LIE/SmallDeformation/LocalAssembler/IntegrationPointDataMatrix.h
index 88001a73ce2..73b28dec804 100644
--- a/ProcessLib/LIE/SmallDeformation/LocalAssembler/IntegrationPointDataMatrix.h
+++ b/ProcessLib/LIE/SmallDeformation/LocalAssembler/IntegrationPointDataMatrix.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_INTEGRATIONPOINTDATAMATRIX_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_INTEGRATIONPOINTDATAMATRIX_H_
+#pragma once
 
 #include <memory>
 #include <vector>
@@ -74,5 +73,3 @@ struct IntegrationPointDataMatrix final
 }  // namespace SmallDeformation
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif // PROCESSLIB_LIE_SMALLDEFORMATION_INTEGRATIONPOINTDATAMATRIX_H_
diff --git a/ProcessLib/LIE/SmallDeformation/LocalAssembler/LocalAssemblerDataFracture.h b/ProcessLib/LIE/SmallDeformation/LocalAssembler/LocalAssemblerDataFracture.h
index 4126d0460d1..f87d2fcf335 100644
--- a/ProcessLib/LIE/SmallDeformation/LocalAssembler/LocalAssemblerDataFracture.h
+++ b/ProcessLib/LIE/SmallDeformation/LocalAssembler/LocalAssemblerDataFracture.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_LOCALASSEMBLERDATA_FRACTURE_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_LOCALASSEMBLERDATA_FRACTURE_H_
+#pragma once
 
 #include "SmallDeformationLocalAssemblerFracture.h"
 
@@ -47,5 +46,3 @@ public:
 }  // namespace SmallDeformation
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_LIE_SMALLDEFORMATION_LOCALASSEMBLERDATA_FRACTURE_H_
diff --git a/ProcessLib/LIE/SmallDeformation/LocalAssembler/LocalAssemblerDataMatrix.h b/ProcessLib/LIE/SmallDeformation/LocalAssembler/LocalAssemblerDataMatrix.h
index 39136ad7f51..ff56709e68a 100644
--- a/ProcessLib/LIE/SmallDeformation/LocalAssembler/LocalAssemblerDataMatrix.h
+++ b/ProcessLib/LIE/SmallDeformation/LocalAssembler/LocalAssemblerDataMatrix.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_LOCALASSEMBLERDATA_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_LOCALASSEMBLERDATA_H_
+#pragma once
 
 #include "SmallDeformationLocalAssemblerMatrix.h"
 
@@ -46,5 +45,3 @@ public:
 }  // namespace SmallDeformation
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_LIE_SMALLDEFORMATION_LOCALASSEMBLERDATA_H_
diff --git a/ProcessLib/LIE/SmallDeformation/LocalAssembler/LocalAssemblerDataMatrixNearFracture.h b/ProcessLib/LIE/SmallDeformation/LocalAssembler/LocalAssemblerDataMatrixNearFracture.h
index 9aff764ade3..4031c89c55c 100644
--- a/ProcessLib/LIE/SmallDeformation/LocalAssembler/LocalAssemblerDataMatrixNearFracture.h
+++ b/ProcessLib/LIE/SmallDeformation/LocalAssembler/LocalAssemblerDataMatrixNearFracture.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_LOCALASSEMBLERDATAMATRIXNEARFRACTURE_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_LOCALASSEMBLERDATAMATRIXNEARFRACTURE_H_
+#pragma once
 
 #include "SmallDeformationLocalAssemblerMatrixNearFracture.h"
 
@@ -48,5 +47,3 @@ public:
 }  // namespace SmallDeformation
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif // PROCESSLIB_LIE_SMALLDEFORMATION_LOCALASSEMBLERDATAMATRIXNEARFRACTURE_H_
diff --git a/ProcessLib/LIE/SmallDeformation/LocalAssembler/LocalDataInitializer.h b/ProcessLib/LIE/SmallDeformation/LocalAssembler/LocalDataInitializer.h
index 1680d53fe4a..02f726adecb 100644
--- a/ProcessLib/LIE/SmallDeformation/LocalAssembler/LocalDataInitializer.h
+++ b/ProcessLib/LIE/SmallDeformation/LocalAssembler/LocalDataInitializer.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_LOCALDATAINITIALIZER_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_LOCALDATAINITIALIZER_H_
+#pragma once
 
 #include <functional>
 #include <memory>
@@ -416,5 +415,3 @@ private:
 #undef ENABLED_ELEMENT_TYPE_TRI
 #undef ENABLED_ELEMENT_TYPE_QUAD
 #undef OGS_ENABLED_ELEMENTS
-
-#endif  // PROCESSLIB_LIE_SMALLDEFORMATION_LOCALDATAINITIALIZER_H_
diff --git a/ProcessLib/LIE/SmallDeformation/LocalAssembler/SecondaryData.h b/ProcessLib/LIE/SmallDeformation/LocalAssembler/SecondaryData.h
index 0987193b909..3fccea11b2c 100644
--- a/ProcessLib/LIE/SmallDeformation/LocalAssembler/SecondaryData.h
+++ b/ProcessLib/LIE/SmallDeformation/LocalAssembler/SecondaryData.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_SECONDARY_DATA_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_SECONDARY_DATA_H_
+#pragma once
 
 namespace ProcessLib
 {
@@ -28,5 +27,3 @@ struct SecondaryData
 }  // namespace SmallDeformation
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_LIE_SMALLDEFORMATION_SECONDARY_DATA_H_
diff --git a/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerFracture-impl.h b/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerFracture-impl.h
index ac0cdce26ff..50ce1cbfae3 100644
--- a/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerFracture-impl.h
+++ b/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerFracture-impl.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_FRACTURE_IMPL_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_FRACTURE_IMPL_H_
+#pragma once
 
 #include "SmallDeformationLocalAssemblerFracture.h"
 
@@ -178,5 +177,3 @@ postTimestepConcrete(std::vector<double> const& /*local_x*/)
 }  // namespace SmallDeformation
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_FRACTURE_IMPL_H_
diff --git a/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerFracture.h b/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerFracture.h
index 744f7e79c15..04a1c8dd87c 100644
--- a/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerFracture.h
+++ b/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerFracture.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_FRACTURE_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_FRACTURE_H_
+#pragma once
 
 #include <vector>
 
@@ -166,5 +165,3 @@ private:
 }  // namespace ProcessLib
 
 #include "SmallDeformationLocalAssemblerFracture-impl.h"
-
-#endif  // PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_FRACTURE_H_
diff --git a/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerInterface.h b/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerInterface.h
index edea655e68a..b082fa43bde 100644
--- a/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerInterface.h
+++ b/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerInterface.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLERINTERFACE_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLERINTERFACE_H_
+#pragma once
 
 #include <vector>
 
@@ -114,5 +113,3 @@ private:
 }  // namespace SmallDeformation
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLERINTERFACE_H_
diff --git a/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerMatrix-impl.h b/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerMatrix-impl.h
index 30cef5babbe..0a49385384f 100644
--- a/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerMatrix-impl.h
+++ b/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerMatrix-impl.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_MATRIX_IMPL_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_MATRIX_IMPL_H_
+#pragma once
 
 #include "SmallDeformationLocalAssemblerMatrix.h"
 
@@ -196,5 +195,3 @@ postTimestepConcrete(std::vector<double> const& /*local_x*/)
 }  // namespace SmallDeformation
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_MATRIX_IMPL_H_
diff --git a/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerMatrix.h b/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerMatrix.h
index 1a1f3c903f8..ded00cf999b 100644
--- a/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerMatrix.h
+++ b/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerMatrix.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_MATRIX_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_MATRIX_H_
+#pragma once
 
 #include <vector>
 
@@ -172,5 +171,3 @@ private:
 }  // namespace ProcessLib
 
 #include "SmallDeformationLocalAssemblerMatrix-impl.h"
-
-#endif  // PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_MATRIX_H_
diff --git a/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerMatrixNearFracture-impl.h b/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerMatrixNearFracture-impl.h
index dc1da39942c..75d9897a41d 100644
--- a/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerMatrixNearFracture-impl.h
+++ b/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerMatrixNearFracture-impl.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_MATRIX_NEAR_FRACTUER_IMPL_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_MATRIX_NEAR_FRACTUER_IMPL_H_
+#pragma once
 
 #include "SmallDeformationLocalAssemblerMatrixNearFracture.h"
 
@@ -282,5 +281,3 @@ postTimestepConcrete(std::vector<double> const& /*local_x*/)
 }  // namespace SmallDeformation
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif // PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_MATRIX_NEAR_FRACTUER_IMPL_H_
diff --git a/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerMatrixNearFracture.h b/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerMatrixNearFracture.h
index 0999833bba1..23ce29b5202 100644
--- a/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerMatrixNearFracture.h
+++ b/ProcessLib/LIE/SmallDeformation/LocalAssembler/SmallDeformationLocalAssemblerMatrixNearFracture.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_MATRIX_NEAR_FRACTUER_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_MATRIX_NEAR_FRACTUER_H_
+#pragma once
 
 #include <vector>
 
@@ -176,5 +175,3 @@ private:
 }  // namespace ProcessLib
 
 #include "SmallDeformationLocalAssemblerMatrixNearFracture-impl.h"
-
-#endif // PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONLOCALASSEMBLER_MATRIX_H_
diff --git a/ProcessLib/LIE/SmallDeformation/SmallDeformationProcess-fwd.h b/ProcessLib/LIE/SmallDeformation/SmallDeformationProcess-fwd.h
index 654f600dcca..f010dfb99b3 100644
--- a/ProcessLib/LIE/SmallDeformation/SmallDeformationProcess-fwd.h
+++ b/ProcessLib/LIE/SmallDeformation/SmallDeformationProcess-fwd.h
@@ -7,11 +7,8 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATION_PROCESS_FWD_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATION_PROCESS_FWD_H_
+#pragma once
 
 #include "SmallDeformationProcess.h"
 
 extern template class ProcessLib::LIE::SmallDeformation::SmallDeformationProcess<2>;
-
-#endif  // PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATION_PROCESS_FWD_H_
diff --git a/ProcessLib/LIE/SmallDeformation/SmallDeformationProcess.h b/ProcessLib/LIE/SmallDeformation/SmallDeformationProcess.h
index 4ce7d67a4d9..3a0e40d93b5 100644
--- a/ProcessLib/LIE/SmallDeformation/SmallDeformationProcess.h
+++ b/ProcessLib/LIE/SmallDeformation/SmallDeformationProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATION_PROCESS_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATION_PROCESS_H_
+#pragma once
 
 #include <cassert>
 
@@ -126,5 +125,3 @@ private:
 }  // namespace SmallDeformation
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATION_PROCESS_H_
diff --git a/ProcessLib/LIE/SmallDeformation/SmallDeformationProcessData.h b/ProcessLib/LIE/SmallDeformation/SmallDeformationProcessData.h
index 52e7ca06e0c..35ecd8cf8a3 100644
--- a/ProcessLib/LIE/SmallDeformation/SmallDeformationProcessData.h
+++ b/ProcessLib/LIE/SmallDeformation/SmallDeformationProcessData.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONPROCESSDATA_H_
-#define PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONPROCESSDATA_H_
+#pragma once
 
 #include <memory>
 
@@ -87,5 +86,3 @@ struct SmallDeformationProcessData
 }  // namespace SmallDeformation
 }  // namespace LIE
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_LIE_SMALLDEFORMATION_SMALLDEFORMATIONPROCESSDATA_H_
diff --git a/ProcessLib/LiquidFlow/CreateLiquidFlowProcess.h b/ProcessLib/LiquidFlow/CreateLiquidFlowProcess.h
index 752208b039d..3e9ed9436e1 100644
--- a/ProcessLib/LiquidFlow/CreateLiquidFlowProcess.h
+++ b/ProcessLib/LiquidFlow/CreateLiquidFlowProcess.h
@@ -10,8 +10,7 @@
  * Created on August 19, 2016, 1:30 PM
  */
 
-#ifndef OGS_CREATELIQUIDFLOWPROCESS_H
-#define OGS_CREATELIQUIDFLOWPROCESS_H
+#pragma once
 
 #include <memory>
 #include "ProcessLib/Process.h"
@@ -29,5 +28,3 @@ std::unique_ptr<Process> createLiquidFlowProcess(
     BaseLib::ConfigTree const& config);
 }  // end of namespace
 }  // end of namespace
-
-#endif /* CREATELIQUIDFLOWPROCESS_H */
diff --git a/ProcessLib/LiquidFlow/LiquidFlowLocalAssembler-impl.h b/ProcessLib/LiquidFlow/LiquidFlowLocalAssembler-impl.h
index 98ee0cbc783..d7a984a2b45 100644
--- a/ProcessLib/LiquidFlow/LiquidFlowLocalAssembler-impl.h
+++ b/ProcessLib/LiquidFlow/LiquidFlowLocalAssembler-impl.h
@@ -10,8 +10,7 @@
  * Created on August 19, 2016, 2:28 PM
  */
 
-#ifndef OGS_LIQUIDFLOWLOCALASSEMBLER_IMPL_H
-#define OGS_LIQUIDFLOWLOCALASSEMBLER_IMPL_H
+#pragma once
 
 #include "LiquidFlowLocalAssembler.h"
 
@@ -257,5 +256,3 @@ void LiquidFlowLocalAssembler<ShapeFunction, IntegrationMethod, GlobalDim>::
 
 }  // end of namespace
 }  // end of namespace
-
-#endif /* OGS_LIQUIDFLOWLOCALASSEMBLER_IMPL_H */
diff --git a/ProcessLib/LiquidFlow/LiquidFlowLocalAssembler.h b/ProcessLib/LiquidFlow/LiquidFlowLocalAssembler.h
index 1ec901fe8e6..d1a5db31306 100644
--- a/ProcessLib/LiquidFlow/LiquidFlowLocalAssembler.h
+++ b/ProcessLib/LiquidFlow/LiquidFlowLocalAssembler.h
@@ -10,8 +10,7 @@
  * Created on August 19, 2016, 2:28 PM
  */
 
-#ifndef OGS_LIQUIDFLOWLOCALASSEMBLER_H
-#define OGS_LIQUIDFLOWLOCALASSEMBLER_H
+#pragma once
 
 #include <vector>
 
@@ -195,5 +194,3 @@ private:
 }  // end of namespace
 
 #include "LiquidFlowLocalAssembler-impl.h"
-
-#endif /* LIQUIDFLOWLOCALASSEMBLER_H */
diff --git a/ProcessLib/LiquidFlow/LiquidFlowMaterialProperties.h b/ProcessLib/LiquidFlow/LiquidFlowMaterialProperties.h
index e526081cb9f..923a9adb358 100644
--- a/ProcessLib/LiquidFlow/LiquidFlowMaterialProperties.h
+++ b/ProcessLib/LiquidFlow/LiquidFlowMaterialProperties.h
@@ -10,8 +10,7 @@
  * Created on August 18, 2016, 11:03 AM
  */
 
-#ifndef OGS_LIQUIDFLOWMATERIALPROPERTIES_H
-#define OGS_LIQUIDFLOWMATERIALPROPERTIES_H
+#pragma once
 
 #include <memory>
 
@@ -106,4 +105,3 @@ private:
 
 }  // end of namespace
 }  // end of namespace
-#endif /* LIQUIDFLOWMATERIALPROPERTIES_H */
diff --git a/ProcessLib/LiquidFlow/LiquidFlowProcess.h b/ProcessLib/LiquidFlow/LiquidFlowProcess.h
index d6e8c6ea876..9e403396cd3 100644
--- a/ProcessLib/LiquidFlow/LiquidFlowProcess.h
+++ b/ProcessLib/LiquidFlow/LiquidFlowProcess.h
@@ -10,8 +10,7 @@
  * Created on August 19, 2016, 1:38 PM
  */
 
-#ifndef OGS_LIQUIDFLOWPROCESS_H
-#define OGS_LIQUIDFLOWPROCESS_H
+#pragma once
 
 #include "NumLib/DOF/LocalToGlobalIndexMap.h"
 #include "ProcessLib/Process.h"
@@ -97,5 +96,3 @@ private:
 
 }  // end of namespace
 }  // end of namespace
-
-#endif /* LIQUIDFLOWPROCESS_H */
diff --git a/ProcessLib/LocalAssemblerInterface.h b/ProcessLib/LocalAssemblerInterface.h
index c4e0fe20f0c..8176485f679 100644
--- a/ProcessLib/LocalAssemblerInterface.h
+++ b/ProcessLib/LocalAssemblerInterface.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LOCALASSEMBLERINTERFACE_H
-#define PROCESSLIB_LOCALASSEMBLERINTERFACE_H
+#pragma once
 
 #include "NumLib/NumericsConfig.h"
 #include "MathLib/Point3d.h"
@@ -80,5 +79,3 @@ private:
 };
 
 } // namespace ProcessLib
-
-#endif // PROCESSLIB_LOCALASSEMBLERINTERFACE_H
diff --git a/ProcessLib/LocalAssemblerTraits.h b/ProcessLib/LocalAssemblerTraits.h
index 7e17a30bdcd..727f0836da1 100644
--- a/ProcessLib/LocalAssemblerTraits.h
+++ b/ProcessLib/LocalAssemblerTraits.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_LOCALASSEMBLERTRAITS_H
-#define PROCESSLIB_LOCALASSEMBLERTRAITS_H
+#pragma once
 
 namespace ProcessLib
 {
@@ -230,5 +229,3 @@ static_assert(OGS_EIGEN_DYNAMIC_SHAPE_MATRICES_FLAG == 1,
 #endif
 
 }
-
-#endif // PROCESSLIB_LOCALASSEMBLERTRAITS_H
diff --git a/ProcessLib/Output.h b/ProcessLib/Output.h
index f94490ffe49..766c5d26ee5 100644
--- a/ProcessLib/Output.h
+++ b/ProcessLib/Output.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_OUTPUT_H
-#define PROCESSLIB_OUTPUT_H
+#pragma once
 
 #include "BaseLib/ConfigTree.h"
 #include "MeshLib/IO/VtkIO/PVDFile.h"
@@ -99,5 +98,3 @@ private:
 };
 
 }
-
-#endif // PROCESSLIB_OUTPUT_H
diff --git a/ProcessLib/Parameter/ConstantParameter.h b/ProcessLib/Parameter/ConstantParameter.h
index a7fe02b503e..d754e75727d 100644
--- a/ProcessLib/Parameter/ConstantParameter.h
+++ b/ProcessLib/Parameter/ConstantParameter.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_CONSTANTPARAMETER_H
-#define PROCESSLIB_CONSTANTPARAMETER_H
+#pragma once
 
 #include "Parameter.h"
 
@@ -54,5 +53,3 @@ std::unique_ptr<ParameterBase> createConstantParameter(
     std::string const& name, BaseLib::ConfigTree const& config);
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_CONSTANTPARAMETER_H
diff --git a/ProcessLib/Parameter/CurveScaledParameter.h b/ProcessLib/Parameter/CurveScaledParameter.h
index 11f3883ad46..57d39ced101 100644
--- a/ProcessLib/Parameter/CurveScaledParameter.h
+++ b/ProcessLib/Parameter/CurveScaledParameter.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_CURVESCALEDPARAMETER_H
-#define PROCESSLIB_CURVESCALEDPARAMETER_H
+#pragma once
 
 #include <map>
 #include "MathLib/InterpolationAlgorithms/PiecewiseLinearInterpolation.h"
@@ -71,5 +70,3 @@ std::unique_ptr<ParameterBase> createCurveScaledParameter(
         curves);
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_CURVESCALEDPARAMETER_H
diff --git a/ProcessLib/Parameter/GroupBasedParameter.h b/ProcessLib/Parameter/GroupBasedParameter.h
index bc4ee771cc4..aa336588c2d 100644
--- a/ProcessLib/Parameter/GroupBasedParameter.h
+++ b/ProcessLib/Parameter/GroupBasedParameter.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_GROUPBASEDPARAMETER_H_
-#define PROCESSLIB_GROUPBASEDPARAMETER_H_
+#pragma once
 
 #include "BaseLib/Error.h"
 #include "MeshLib/PropertyVector.h"
@@ -91,5 +90,3 @@ std::unique_ptr<ParameterBase> createGroupBasedParameter(
     MeshLib::Mesh const& mesh);
 
 }  // ProcessLib
-
-#endif // PROCESSLIB_GROUPBASEDPARAMETER_H_
diff --git a/ProcessLib/Parameter/MeshElementParameter.h b/ProcessLib/Parameter/MeshElementParameter.h
index 2d0b7c04830..966fe7dd9bb 100644
--- a/ProcessLib/Parameter/MeshElementParameter.h
+++ b/ProcessLib/Parameter/MeshElementParameter.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_MESHELEMENTPARAMETER_H
-#define PROCESSLIB_MESHELEMENTPARAMETER_H
+#pragma once
 
 #include "Parameter.h"
 
@@ -60,5 +59,3 @@ std::unique_ptr<ParameterBase> createMeshElementParameter(
     MeshLib::Mesh const& mesh);
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_MESHELEMENTPARAMETER_H
diff --git a/ProcessLib/Parameter/MeshNodeParameter.h b/ProcessLib/Parameter/MeshNodeParameter.h
index b181aca1f95..a6d1da482be 100644
--- a/ProcessLib/Parameter/MeshNodeParameter.h
+++ b/ProcessLib/Parameter/MeshNodeParameter.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_MESHNODEPARAMETER_H
-#define PROCESSLIB_MESHNODEPARAMETER_H
+#pragma once
 
 #include "Parameter.h"
 
@@ -60,5 +59,3 @@ std::unique_ptr<ParameterBase> createMeshNodeParameter(
     MeshLib::Mesh const& mesh);
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_MESHNODEPARAMETER_H
diff --git a/ProcessLib/Parameter/Parameter.h b/ProcessLib/Parameter/Parameter.h
index c44c3118985..b9a81894414 100644
--- a/ProcessLib/Parameter/Parameter.h
+++ b/ProcessLib/Parameter/Parameter.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_PARAMETER_H_
-#define PROCESS_LIB_PARAMETER_H_
+#pragma once
 
 #include <map>
 #include <memory>
@@ -87,5 +86,3 @@ std::unique_ptr<ParameterBase> createParameter(
         curves);
 
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_PARAMETER_H_
diff --git a/ProcessLib/Parameter/SpatialPosition.h b/ProcessLib/Parameter/SpatialPosition.h
index ca2ceac8a25..417a487747a 100644
--- a/ProcessLib/Parameter/SpatialPosition.h
+++ b/ProcessLib/Parameter/SpatialPosition.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_SPATIALPOSITION_H
-#define PROCESSLIB_SPATIALPOSITION_H
+#pragma once
 
 #include <boost/optional.hpp>
 #include "MathLib/TemplatePoint.h"
@@ -89,5 +88,3 @@ private:
 };
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_SPATIALPOSITION_H
diff --git a/ProcessLib/Process.h b/ProcessLib/Process.h
index ffdc235e180..fcd4b82ec02 100644
--- a/ProcessLib/Process.h
+++ b/ProcessLib/Process.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_PROCESS_H_
-#define PROCESS_LIB_PROCESS_H_
+#pragma once
 
 #include "NumLib/ODESolver/NonlinearSolver.h"
 #include "NumLib/ODESolver/ODESystem.h"
@@ -206,5 +205,3 @@ private:
 };
 
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_PROCESS_H_
diff --git a/ProcessLib/ProcessOutput.h b/ProcessLib/ProcessOutput.h
index f1559b3c892..f0bd16bda57 100644
--- a/ProcessLib/ProcessOutput.h
+++ b/ProcessLib/ProcessOutput.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_PROCESSOUTPUT_H
-#define PROCESSLIB_PROCESSOUTPUT_H
+#pragma once
 
 #include "ProcessVariable.h"
 #include "SecondaryVariable.h"
@@ -42,6 +41,3 @@ void doProcessOutput(
         ProcessOutput const& process_output);
 
 } // ProcessLib
-
-
-#endif // PROCESSLIB_PROCESSOUTPUT_H
diff --git a/ProcessLib/ProcessVariable.h b/ProcessLib/ProcessVariable.h
index 0bcbd1f4847..56aa3c9e797 100644
--- a/ProcessLib/ProcessVariable.h
+++ b/ProcessLib/ProcessVariable.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_PROCESS_VARIABLE_H_
-#define PROCESS_LIB_PROCESS_VARIABLE_H_
+#pragma once
 
 #include "ProcessLib/BoundaryCondition/BoundaryCondition.h"
 #include "ProcessLib/BoundaryCondition/BoundaryConditionConfig.h"
@@ -91,5 +90,3 @@ private:
 };
 
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_PROCESS_VARIABLE_H_
diff --git a/ProcessLib/RichardsFlow/CreateRichardsFlowProcess.h b/ProcessLib/RichardsFlow/CreateRichardsFlowProcess.h
index 3ed760086ad..b97b943af25 100644
--- a/ProcessLib/RichardsFlow/CreateRichardsFlowProcess.h
+++ b/ProcessLib/RichardsFlow/CreateRichardsFlowProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_CREATE_RICHARDSFLOWPROCESS_H_
-#define PROCESS_LIB_CREATE_RICHARDSFLOWPROCESS_H_
+#pragma once
 
 #include <memory>
 #include "ProcessLib/Process.h"
@@ -29,5 +28,3 @@ std::unique_ptr<Process> createRichardsFlowProcess(
         curves);
 }  // namespace RichardsFlow
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_CREATE_RICHARDSFLOWPROCESS_H_
diff --git a/ProcessLib/RichardsFlow/RichardsFlowFEM.h b/ProcessLib/RichardsFlow/RichardsFlowFEM.h
index ce1d68a53bf..55cae850bef 100644
--- a/ProcessLib/RichardsFlow/RichardsFlowFEM.h
+++ b/ProcessLib/RichardsFlow/RichardsFlowFEM.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_RICHARDSFLOW_FEM_H_
-#define PROCESS_LIB_RICHARDSFLOW_FEM_H_
+#pragma once
 
 #include <vector>
 
@@ -188,5 +187,3 @@ private:
 
 }  // namespace RichardsFlow
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_RichardsFlow_FEM_H_
diff --git a/ProcessLib/RichardsFlow/RichardsFlowProcess.h b/ProcessLib/RichardsFlow/RichardsFlowProcess.h
index 547fa3c7dc1..954ba7af7b8 100644
--- a/ProcessLib/RichardsFlow/RichardsFlowProcess.h
+++ b/ProcessLib/RichardsFlow/RichardsFlowProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_RICHARDSFLOWPROCESS_H_
-#define PROCESS_LIB_RICHARDSFLOWPROCESS_H_
+#pragma once
 
 #include "NumLib/Extrapolation/LocalLinearLeastSquaresExtrapolator.h"
 #include "ProcessLib/Process.h"
@@ -65,5 +64,3 @@ private:
 
 }  // namespace RichardsFlow
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_RICHARDSFLOWPROCESS_H_
diff --git a/ProcessLib/RichardsFlow/RichardsFlowProcessData.h b/ProcessLib/RichardsFlow/RichardsFlowProcessData.h
index 92f6daef0c8..4d7ea9ebb51 100644
--- a/ProcessLib/RichardsFlow/RichardsFlowProcessData.h
+++ b/ProcessLib/RichardsFlow/RichardsFlowProcessData.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_RICHARDSFLOW_RICHARDSFLOWPROCESSDATA_H
-#define PROCESSLIB_RICHARDSFLOW_RICHARDSFLOWPROCESSDATA_H
+#pragma once
 
 namespace MeshLib
 {
@@ -85,5 +84,3 @@ struct RichardsFlowProcessData
 
 }  // namespace RichardsFlow
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_RichardsFlow_RichardsFlowPROCESSDATA_H
diff --git a/ProcessLib/SecondaryVariable.h b/ProcessLib/SecondaryVariable.h
index 3e1ba69aa13..de54dec8710 100644
--- a/ProcessLib/SecondaryVariable.h
+++ b/ProcessLib/SecondaryVariable.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_SECONDARY_VARIABLE_H
-#define PROCESSLIB_SECONDARY_VARIABLE_H
+#pragma once
 
 #include "BaseLib/ConfigTree.h"
 #include "BaseLib/uniqueInsert.h"
@@ -181,5 +180,3 @@ SecondaryVariableFunctions makeExtrapolator(
 }
 
 }  // namespace ProcessLib
-
-#endif // PROCESSLIB_SECONDARY_VARIABLE_H
diff --git a/ProcessLib/SecondaryVariableContext.h b/ProcessLib/SecondaryVariableContext.h
index cbc8dcf83de..717db74124f 100644
--- a/ProcessLib/SecondaryVariableContext.h
+++ b/ProcessLib/SecondaryVariableContext.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_SECONDARYVARIABLECONTEXT_H
-#define PROCESSLIB_SECONDARYVARIABLECONTEXT_H
+#pragma once
 
 namespace ProcessLib
 {
@@ -27,5 +26,3 @@ public:
 };
 
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_SECONDARYVARIABLECONTEXT_H
diff --git a/ProcessLib/SmallDeformation/CreateLocalAssemblers.h b/ProcessLib/SmallDeformation/CreateLocalAssemblers.h
index 4482baccbf2..efeb85943ba 100644
--- a/ProcessLib/SmallDeformation/CreateLocalAssemblers.h
+++ b/ProcessLib/SmallDeformation/CreateLocalAssemblers.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef PROCESSLIB_SMALLDEFORMATION_CREATE_LOCAL_ASSEMBLERS_H_
-#define PROCESSLIB_SMALLDEFORMATION_CREATE_LOCAL_ASSEMBLERS_H_
+#pragma once
 
 #include <vector>
 
@@ -102,5 +101,3 @@ void createLocalAssemblers(
 }  // SmallDeformation
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_SMALLDEFORMATION_CREATE_LOCAL_ASSEMBLERS_H_
diff --git a/ProcessLib/SmallDeformation/CreateSmallDeformationProcess.h b/ProcessLib/SmallDeformation/CreateSmallDeformationProcess.h
index 5908e3db138..45d2a6e7638 100644
--- a/ProcessLib/SmallDeformation/CreateSmallDeformationProcess.h
+++ b/ProcessLib/SmallDeformation/CreateSmallDeformationProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_CREATESMALLDEFORMATIONPROCESS_H_
-#define PROCESS_LIB_CREATESMALLDEFORMATIONPROCESS_H_
+#pragma once
 
 #include "MaterialLib/SolidModels/CreateLubby2.h"
 #include "ProcessLib/Process.h"
@@ -28,5 +27,3 @@ std::unique_ptr<Process> createSmallDeformationProcess(
 
 }  // namespace SmallDeformation
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_CREATESMALLDEFORMATIONPROCESS_H_
diff --git a/ProcessLib/SmallDeformation/LocalDataInitializer.h b/ProcessLib/SmallDeformation/LocalDataInitializer.h
index 3a2e388593e..d763ffdb296 100644
--- a/ProcessLib/SmallDeformation/LocalDataInitializer.h
+++ b/ProcessLib/SmallDeformation/LocalDataInitializer.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_SMALLDEFORMATION_LOCALDATAINITIALIZER_H_
-#define PROCESSLIB_SMALLDEFORMATION_LOCALDATAINITIALIZER_H_
+#pragma once
 
 #include <functional>
 #include <memory>
@@ -303,5 +302,3 @@ private:
 #undef ENABLED_ELEMENT_TYPE_TRI
 #undef ENABLED_ELEMENT_TYPE_QUAD
 #undef OGS_ENABLED_ELEMENTS
-
-#endif  // PROCESSLIB_SMALLDEFORMATION_LOCALDATAINITIALIZER_H_
diff --git a/ProcessLib/SmallDeformation/SmallDeformationFEM.h b/ProcessLib/SmallDeformation/SmallDeformationFEM.h
index 9f7df1474a3..c2c2a02c9fa 100644
--- a/ProcessLib/SmallDeformation/SmallDeformationFEM.h
+++ b/ProcessLib/SmallDeformation/SmallDeformationFEM.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_SMALLDEFORMATION_FEM_H_
-#define PROCESS_LIB_SMALLDEFORMATION_FEM_H_
+#pragma once
 
 #include <memory>
 #include <vector>
@@ -440,5 +439,3 @@ public:
 
 }  // namespace SmallDeformation
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_SMALLDEFORMATION_FEM_H_
diff --git a/ProcessLib/SmallDeformation/SmallDeformationProcess-fwd.h b/ProcessLib/SmallDeformation/SmallDeformationProcess-fwd.h
index 8972b428a41..0022328eded 100644
--- a/ProcessLib/SmallDeformation/SmallDeformationProcess-fwd.h
+++ b/ProcessLib/SmallDeformation/SmallDeformationProcess-fwd.h
@@ -7,12 +7,9 @@
  *
  */
 
-#ifndef PROCESS_LIB_SMALLDEFORMATIONPROCESS_FWD_H_
-#define PROCESS_LIB_SMALLDEFORMATIONPROCESS_FWD_H_
+#pragma once
 
 #include "SmallDeformationProcess.h"
 
 extern template class ProcessLib::SmallDeformation::SmallDeformationProcess<2>;
 extern template class ProcessLib::SmallDeformation::SmallDeformationProcess<3>;
-
-#endif  // PROCESS_LIB_SMALLDEFORMATIONPROCESS_FWD_H_
diff --git a/ProcessLib/SmallDeformation/SmallDeformationProcess.h b/ProcessLib/SmallDeformation/SmallDeformationProcess.h
index dedff1753a9..a5c92921db6 100644
--- a/ProcessLib/SmallDeformation/SmallDeformationProcess.h
+++ b/ProcessLib/SmallDeformation/SmallDeformationProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_SMALLDEFORMATIONPROCESS_H_
-#define PROCESS_LIB_SMALLDEFORMATIONPROCESS_H_
+#pragma once
 
 #include <cassert>
 
@@ -201,5 +200,3 @@ private:
 
 }  // namespace SmallDeformation
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_SMALLDEFORMATIONPROCESS_H_
diff --git a/ProcessLib/SmallDeformation/SmallDeformationProcessData.h b/ProcessLib/SmallDeformation/SmallDeformationProcessData.h
index 75e67513df3..9f6a5115f06 100644
--- a/ProcessLib/SmallDeformation/SmallDeformationProcessData.h
+++ b/ProcessLib/SmallDeformation/SmallDeformationProcessData.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_SMALLDEFORMATION_SMALLDEFORMATIONPROCESSDATA_H_
-#define PROCESSLIB_SMALLDEFORMATION_SMALLDEFORMATIONPROCESSDATA_H_
+#pragma once
 
 namespace MeshLib
 {
@@ -51,5 +50,3 @@ struct SmallDeformationProcessData
 
 }  // namespace SmallDeformation
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_SMALLDEFORMATION_SMALLDEFORMATIONPROCESSDATA_H_
diff --git a/ProcessLib/TES/CreateTESProcess.h b/ProcessLib/TES/CreateTESProcess.h
index 1af2b064e4c..2c2d1bd42c1 100644
--- a/ProcessLib/TES/CreateTESProcess.h
+++ b/ProcessLib/TES/CreateTESProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_CREATE_TESPROCESS_H_
-#define PROCESS_LIB_CREATE_TESPROCESS_H_
+#pragma once
 
 #include <memory>
 #include "ProcessLib/Process.h"
@@ -27,5 +26,3 @@ std::unique_ptr<Process> createTESProcess(
 
 }  // namespace TES
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_CREATE_TESPROCESS_H_
diff --git a/ProcessLib/TES/TESAssemblyParams.h b/ProcessLib/TES/TESAssemblyParams.h
index 28db0264334..473db2e200c 100644
--- a/ProcessLib/TES/TESAssemblyParams.h
+++ b/ProcessLib/TES/TESAssemblyParams.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_TESPROCESS_NOTPL_H_
-#define PROCESS_LIB_TESPROCESS_NOTPL_H_
+#pragma once
 
 #include <Eigen/Eigen>
 #include <Eigen/Sparse>
@@ -81,5 +80,3 @@ struct AssemblyParams
 }  // namespace TES
 
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_TESPROCESS_NOTPL_H_
diff --git a/ProcessLib/TES/TESLocalAssembler-impl.h b/ProcessLib/TES/TESLocalAssembler-impl.h
index 04678c52a6a..72cfe4c725e 100644
--- a/ProcessLib/TES/TESLocalAssembler-impl.h
+++ b/ProcessLib/TES/TESLocalAssembler-impl.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef PROCESS_LIB_TES_FEM_IMPL_H_
-#define PROCESS_LIB_TES_FEM_IMPL_H_
+#pragma once
 
 #include "MaterialLib/Adsorption/Adsorption.h"
 #include "MathLib/LinAlg/Eigen/EigenMapTools.h"
@@ -276,5 +275,3 @@ bool TESLocalAssembler<
 
 }  // namespace TES
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_TES_FEM_IMPL_H_
diff --git a/ProcessLib/TES/TESLocalAssembler.h b/ProcessLib/TES/TESLocalAssembler.h
index e3b11df0c0f..2b00c356137 100644
--- a/ProcessLib/TES/TESLocalAssembler.h
+++ b/ProcessLib/TES/TESLocalAssembler.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_TES_FEM_H_
-#define PROCESS_LIB_TES_FEM_H_
+#pragma once
 
 #include <memory>
 #include <vector>
@@ -133,5 +132,3 @@ private:
 }  // namespace ProcessLib
 
 #include "TESLocalAssembler-impl.h"
-
-#endif  // PROCESS_LIB_TES_FEM_H_
diff --git a/ProcessLib/TES/TESLocalAssemblerData.h b/ProcessLib/TES/TESLocalAssemblerData.h
index 502b45cd20a..23baf2a421e 100644
--- a/ProcessLib/TES/TESLocalAssemblerData.h
+++ b/ProcessLib/TES/TESLocalAssemblerData.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_TES_TESLOCALASSEMBLERDATA_H
-#define PROCESSLIB_TES_TESLOCALASSEMBLERDATA_H
+#pragma once
 
 #include "TESAssemblyParams.h"
 
@@ -56,4 +55,3 @@ struct TESLocalAssemblerData
 };
 }
 }  // namespaces
-#endif  // PROCESSLIB_TES_TESLOCALASSEMBLERDATA_H
diff --git a/ProcessLib/TES/TESLocalAssemblerInner-fwd.h b/ProcessLib/TES/TESLocalAssemblerInner-fwd.h
index 7051dadfb3e..1f32d85c71b 100644
--- a/ProcessLib/TES/TESLocalAssemblerInner-fwd.h
+++ b/ProcessLib/TES/TESLocalAssemblerInner-fwd.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_TESFEM_DATA_FWD_H_
-#define PROCESS_LIB_TESFEM_DATA_FWD_H_
+#pragma once
 
 #include "TESLocalAssemblerInner.h"
 
@@ -29,5 +28,3 @@ static_assert(OGS_EIGEN_DYNAMIC_SHAPE_MATRICES_FLAG == 0,
 #endif
 }
 }
-
-#endif  // PROCESS_LIB_TESFEM_DATA_FWD_H_
diff --git a/ProcessLib/TES/TESLocalAssemblerInner-impl.h b/ProcessLib/TES/TESLocalAssemblerInner-impl.h
index 20d2c13aecd..2c3ce111446 100644
--- a/ProcessLib/TES/TESLocalAssemblerInner-impl.h
+++ b/ProcessLib/TES/TESLocalAssemblerInner-impl.h
@@ -10,8 +10,7 @@
  * not all of OGS6 has to be recompiled every time a small change is done.
  */
 
-#ifndef PROCESS_LIB_TESFEM_DATA_IMPL_H_
-#define PROCESS_LIB_TESFEM_DATA_IMPL_H_
+#pragma once
 
 #include <cstdio>
 #include <iostream>
@@ -313,5 +312,3 @@ void TESLocalAssemblerInner<Traits>::preEachAssemble()
 }  // namespace TES
 
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_TESFEM_DATA_IMPL_H_
diff --git a/ProcessLib/TES/TESLocalAssemblerInner.h b/ProcessLib/TES/TESLocalAssemblerInner.h
index 3cdce8e84ab..70c2c97fee0 100644
--- a/ProcessLib/TES/TESLocalAssemblerInner.h
+++ b/ProcessLib/TES/TESLocalAssemblerInner.h
@@ -10,8 +10,7 @@
  * not all of OGS6 has to be recompiled every time a small change is done.
  */
 
-#ifndef PROCESS_LIB_TES_FEM_NOTPL_H_
-#define PROCESS_LIB_TES_FEM_NOTPL_H_
+#pragma once
 
 #include "NumLib/Fem/ShapeMatrixPolicy.h"
 #include "ProcessLib/LocalAssemblerTraits.h"
@@ -73,5 +72,3 @@ private:
 }  // namespace ProcessLib
 
 #include "TESLocalAssemblerInner-impl.h"
-
-#endif  // PROCESS_LIB_TES_FEM_NOTPL_H_
diff --git a/ProcessLib/TES/TESOGS5MaterialModels.h b/ProcessLib/TES/TESOGS5MaterialModels.h
index 0bbcf23b7dc..9b2ccd3920b 100644
--- a/ProcessLib/TES/TESOGS5MaterialModels.h
+++ b/ProcessLib/TES/TESOGS5MaterialModels.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef PROCESSLIB_TES_OGS5MATERIALMODELS
-#define PROCESSLIB_TES_OGS5MATERIALMODELS
+#pragma once
 
 #include "MaterialLib/PhysicalConstant.h"
 #include "TESAssemblyParams.h"
@@ -404,5 +403,3 @@ inline double fluid_heat_conductivity(const double p,
 
 }  // TES
 }  // ProcessLib
-
-#endif  // PROCESSLIB_TES_OGS5MATERIALMODELS
diff --git a/ProcessLib/TES/TESProcess.h b/ProcessLib/TES/TESProcess.h
index 0cc71f9648a..34073e1a025 100644
--- a/ProcessLib/TES/TESProcess.h
+++ b/ProcessLib/TES/TESProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_TESPROCESS_H_
-#define PROCESS_LIB_TESPROCESS_H_
+#pragma once
 
 #include "NumLib/DOF/LocalToGlobalIndexMap.h"
 #include "ProcessLib/Process.h"
@@ -92,5 +91,3 @@ private:
 }  // namespace TES
 
 }  // namespace ProcessLib
-
-#endif  // PROCESS_LIB_TESPROCESS_H_
diff --git a/ProcessLib/TES/TESReactionAdaptor.h b/ProcessLib/TES/TESReactionAdaptor.h
index b0a128aeb27..aeca2bf219e 100644
--- a/ProcessLib/TES/TESReactionAdaptor.h
+++ b/ProcessLib/TES/TESReactionAdaptor.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_TES_TESREACTIONADAPTOR_H
-#define PROCESSLIB_TES_TESREACTIONADAPTOR_H
+#pragma once
 
 #include <memory>
 #include <vector>
@@ -130,4 +129,3 @@ private:
 
 }  // namespace TES
 }  // namespace ProcessLib
-#endif  // PROCESSLIB_TES_TESREACTIONADAPTOR_H
diff --git a/ProcessLib/TwoPhaseFlowWithPP/CreateTwoPhaseFlowWithPPProcess.h b/ProcessLib/TwoPhaseFlowWithPP/CreateTwoPhaseFlowWithPPProcess.h
index b525abe1187..9f46501de39 100644
--- a/ProcessLib/TwoPhaseFlowWithPP/CreateTwoPhaseFlowWithPPProcess.h
+++ b/ProcessLib/TwoPhaseFlowWithPP/CreateTwoPhaseFlowWithPPProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef OGS_CREATETWOPHASEFLOWWITHPPPROCESS_H
-#define OGS_CREATETWOPHASEFLOWWITHPPPROCESS_H
+#pragma once
 
 #include <memory>
 #include "ProcessLib/Process.h"
@@ -29,5 +28,3 @@ std::unique_ptr<Process> CreateTwoPhaseFlowWithPPProcess(
         curves);
 }  // end of namespace
 }  // end of namespace
-
-#endif /* CREATETWOPHASEFLOWWITHPPPROCESS_H */
diff --git a/ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPLocalAssembler-impl.h b/ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPLocalAssembler-impl.h
index e4a039bc167..939b6644688 100644
--- a/ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPLocalAssembler-impl.h
+++ b/ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPLocalAssembler-impl.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef OGS_TWOPHASEFLOWWITHPPLOCALASSEMBLER_IMPL_H
-#define OGS_TWOPHASEFLOWWITHPPLOCALASSEMBLER_IMPL_H
+#pragma once
 
 #include "TwoPhaseFlowWithPPLocalAssembler.h"
 
@@ -204,5 +203,3 @@ void TwoPhaseFlowWithPPLocalAssembler<
 
 }  // end of namespace
 }  // end of namespace
-
-#endif
diff --git a/ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPLocalAssembler.h b/ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPLocalAssembler.h
index 1cf5dbde2b5..8953d93c893 100644
--- a/ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPLocalAssembler.h
+++ b/ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPLocalAssembler.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef OGS_TWOPHASEFLOWWITHPPLOCALASSEMBLER_H
-#define OGS_TWOPHASEFLOWWITHPPLOCALASSEMBLER_H
+#pragma once
 
 #include <vector>
 
@@ -136,5 +135,3 @@ private:
 }  // end of namespace
 
 #include "TwoPhaseFlowWithPPLocalAssembler-impl.h"
-
-#endif /* TWOPHASEFLOWWITHPPLOCALASSEMBLER_H */
diff --git a/ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPProcess.h b/ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPProcess.h
index c0b05004dfb..ee012075e0e 100644
--- a/ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPProcess.h
+++ b/ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPProcess.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef OGS_TWOPHASEFLOWWITHPPPROCESS_H
-#define OGS_TWOPHASEFLOWWITHPPPROCESS_H
+#pragma once
 
 #include "MaterialLib/TwoPhaseModels/TwoPhaseFlowWithPPMaterialProperties.h"
 #include "MathLib/InterpolationAlgorithms/PiecewiseLinearInterpolation.h"
@@ -75,5 +74,3 @@ private:
 
 }  // end of namespace
 }  // end of namespace
-
-#endif /* TWOPHASEFLOWWITHPPPROCESS_H */
diff --git a/ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPProcessData.h b/ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPProcessData.h
index 0556490f3a7..6da20a21694 100644
--- a/ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPProcessData.h
+++ b/ProcessLib/TwoPhaseFlowWithPP/TwoPhaseFlowWithPPProcessData.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_TWOPHASEFLOWWITHPP_TWOPHASEFLOWWITHPPPROCESSDATA_H
-#define PROCESSLIB_TWOPHASEFLOWWITHPP_TWOPHASEFLOWWITHPPPROCESSDATA_H
+#pragma once
 
 namespace MeshLib
 {
@@ -83,5 +82,3 @@ struct TwoPhaseFlowWithPPProcessData
 
 }  // namespace TwoPhaseFlowWithPP
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_TwoPhaseFlowWithPP_TwoPhaseFlowWithPPPROCESSDATA_H
diff --git a/ProcessLib/UncoupledProcessesTimeLoop.h b/ProcessLib/UncoupledProcessesTimeLoop.h
index 93985e61318..3d6f74dde46 100644
--- a/ProcessLib/UncoupledProcessesTimeLoop.h
+++ b/ProcessLib/UncoupledProcessesTimeLoop.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_UNCOUPLED_PROCESSES_TIMELOOP
-#define PROCESSLIB_UNCOUPLED_PROCESSES_TIMELOOP
+#pragma once
 
 #include <memory>
 #include <logog/include/logog.hpp>
@@ -52,5 +51,3 @@ std::unique_ptr<UncoupledProcessesTimeLoop> createUncoupledProcessesTimeLoop(
         nonlinear_solvers);
 
 }  // namespace ProcessLib
-
-#endif  // PROCESSLIB_UNCOUPLED_PROCESSES_TIMELOOP
diff --git a/ProcessLib/Utils/CreateLocalAssemblers.h b/ProcessLib/Utils/CreateLocalAssemblers.h
index e37a8253946..13bd2c7eeb7 100644
--- a/ProcessLib/Utils/CreateLocalAssemblers.h
+++ b/ProcessLib/Utils/CreateLocalAssemblers.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef PROCESSLIB_UTILS_CREATE_LOCAL_ASSEMBLERS_H_
-#define PROCESSLIB_UTILS_CREATE_LOCAL_ASSEMBLERS_H_
+#pragma once
 
 #include <vector>
 
@@ -101,5 +100,3 @@ void createLocalAssemblers(
 }
 
 }  // ProcessLib
-
-#endif  // PROCESSLIB_UTILS_CREATE_LOCAL_ASSEMBLERS_H_
diff --git a/ProcessLib/Utils/InitShapeMatrices.h b/ProcessLib/Utils/InitShapeMatrices.h
index f72add26f2d..41243128125 100644
--- a/ProcessLib/Utils/InitShapeMatrices.h
+++ b/ProcessLib/Utils/InitShapeMatrices.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef PROCESSLIB_UTILS_INIT_SHAPE_MATRICES_H_
-#define PROCESSLIB_UTILS_INIT_SHAPE_MATRICES_H_
+#pragma once
 
 #include <vector>
 
@@ -58,6 +57,3 @@ double interpolateXCoordinate(
 }
 
 } // ProcessLib
-
-
-#endif // PROCESSLIB_UTILS_INIT_SHAPE_MATRICES_H_
diff --git a/ProcessLib/Utils/LocalDataInitializer.h b/ProcessLib/Utils/LocalDataInitializer.h
index 81dbc4b9a01..539b2eb0993 100644
--- a/ProcessLib/Utils/LocalDataInitializer.h
+++ b/ProcessLib/Utils/LocalDataInitializer.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESS_LIB_LOCALDATAINITIALIVER_H_
-#define PROCESS_LIB_LOCALDATAINITIALIVER_H_
+#pragma once
 
 #include <functional>
 #include <memory>
@@ -396,5 +395,3 @@ private:
 #undef ENABLED_ELEMENT_TYPE_TRI
 #undef ENABLED_ELEMENT_TYPE_QUAD
 #undef OGS_ENABLED_ELEMENTS
-
-#endif  // PROCESS_LIB_LOCALDATAINITIALIVER_H_
diff --git a/ProcessLib/Utils/ParseSecondaryVariables.h b/ProcessLib/Utils/ParseSecondaryVariables.h
index 6ffafa166f4..6268ed8c27d 100644
--- a/ProcessLib/Utils/ParseSecondaryVariables.h
+++ b/ProcessLib/Utils/ParseSecondaryVariables.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_UTILS_PARSESECONDARYVARIABLES_H
-#define PROCESSLIB_UTILS_PARSESECONDARYVARIABLES_H
+#pragma once
 
 namespace BaseLib { class ConfigTree; }
 namespace ProcessLib { class SecondaryVariableCollection; }
@@ -22,5 +21,3 @@ void parseSecondaryVariables(
     NumLib::NamedFunctionCaller& named_function_caller);
 
 } // namespace ProcessLib
-
-#endif // PROCESSLIB_UTILS_PARSESECONDARYVARIABLES_H
diff --git a/ProcessLib/Utils/ProcessUtils.h b/ProcessLib/Utils/ProcessUtils.h
index 9590fd2f8b8..c7aa7de6f33 100644
--- a/ProcessLib/Utils/ProcessUtils.h
+++ b/ProcessLib/Utils/ProcessUtils.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_UTILS_PROCESSUTILS_H
-#define PROCESSLIB_UTILS_PROCESSUTILS_H
+#pragma once
 
 #include <vector>
 #include "BaseLib/ConfigTree.h"
@@ -121,5 +120,3 @@ Parameter<ParameterDataType>& findParameter(
     return findParameter<ParameterDataType>(name, parameters, num_components);
 }
 }  // ProcessLib
-
-#endif  // PROCESSLIB_UTILS_PROCESSUTILS_H
diff --git a/ProcessLib/VariableTransformation.h b/ProcessLib/VariableTransformation.h
index a1286d762c7..8c82fc497ab 100644
--- a/ProcessLib/VariableTransformation.h
+++ b/ProcessLib/VariableTransformation.h
@@ -9,8 +9,7 @@
  * not all of OGS6 has to be recompiled every time a small change is done.
  */
 
-#ifndef PROCESSLIB_VARIABLETRANSFORMATION_H
-#define PROCESSLIB_VARIABLETRANSFORMATION_H
+#pragma once
 
 namespace ProcessLib
 {
@@ -84,4 +83,3 @@ private:
 typedef TrafoScale Trafo;
 
 }
-#endif // PROCESSLIB_VARIABLETRANSFORMATION_H
diff --git a/ProcessLib/VectorMatrixAssembler.h b/ProcessLib/VectorMatrixAssembler.h
index eaaadc1fbd8..a017a00ab00 100644
--- a/ProcessLib/VectorMatrixAssembler.h
+++ b/ProcessLib/VectorMatrixAssembler.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef PROCESSLIB_VECTORMATRIXASSEMBLER_H_
-#define PROCESSLIB_VECTORMATRIXASSEMBLER_H_
+#pragma once
 
 #include <vector>
 #include "NumLib/NumericsConfig.h"
@@ -65,5 +64,3 @@ private:
 };
 
 }   // namespace ProcessLib
-
-#endif  // PROCESSLIB_VECTORMATRIXASSEMBLER_H_
diff --git a/Tests/GeoLib/AutoCheckGenerators.h b/Tests/GeoLib/AutoCheckGenerators.h
index 239859dec33..28c799d0939 100644
--- a/Tests/GeoLib/AutoCheckGenerators.h
+++ b/Tests/GeoLib/AutoCheckGenerators.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef TESTS_GEOLIB_AUTOCHECKGENERATORS_H_
-#define TESTS_GEOLIB_AUTOCHECKGENERATORS_H_
+#pragma once
 
 #include <cmath>
 #include <memory>
@@ -101,5 +100,3 @@ struct PairSegmentGeneratorXY
 };
 
 }  // namespace autocheck
-
-#endif  // TESTS_GEOLIB_AUTOCHECKGENERATORS_H_
diff --git a/Tests/InstanceCounter.h b/Tests/InstanceCounter.h
index 573587002b8..2556a476977 100644
--- a/Tests/InstanceCounter.h
+++ b/Tests/InstanceCounter.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TESTS_INSTANCECOUNTER_H
-#define TESTS_INSTANCECOUNTER_H
+#pragma once
 
 template <class T>
 class InstanceCounter
@@ -71,5 +70,3 @@ int InstanceCounter<T>::_num_destroyed = 0;
     (num_move) = InstanceCounter<type>::getNumberOfMoves();             \
     (num_copy) = InstanceCounter<type>::getNumberOfCopies();            \
     (num_inst) = InstanceCounter<type>::getNumberOfInstances()
-
-#endif // TESTS_INSTANCECOUNTER_H
diff --git a/Tests/MathLib/AutoCheckTools.h b/Tests/MathLib/AutoCheckTools.h
index f82a59489be..eed06985275 100644
--- a/Tests/MathLib/AutoCheckTools.h
+++ b/Tests/MathLib/AutoCheckTools.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef TESTS_MATHLIB_AUTOCHECKTOOLS_H_
-#define TESTS_MATHLIB_AUTOCHECKTOOLS_H_
+#pragma once
 
 #include <Eigen/Dense>
 #include <autocheck/autocheck.hpp>
@@ -139,4 +138,3 @@ struct progressivelySmallerGenerator
 };
 
 }  // namespace autocheck
-#endif  // TESTS_MATHLIB_AUTOCHECKTOOLS_H_
diff --git a/Tests/NumLib/CoordinatesMappingTestData/TestHex8.h b/Tests/NumLib/CoordinatesMappingTestData/TestHex8.h
index ace84a91a0a..5072b65d4fb 100644
--- a/Tests/NumLib/CoordinatesMappingTestData/TestHex8.h
+++ b/Tests/NumLib/CoordinatesMappingTestData/TestHex8.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef COORDINATESMAPPINGTESTDATA_TESTHEX8_H_
-#define COORDINATESMAPPINGTESTDATA_TESTHEX8_H_
+#pragma once
 
 #include "MeshLib/Elements/Hex.h"
 #include "NumLib/Fem/ShapeFunction/ShapeHex8.h"
@@ -121,7 +120,3 @@ const double TestHex8::cl_exp_detJ = -1.;
 const double TestHex8::ze_exp_J[dim*dim] = {1.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 0.0};
 
 }
-
-#endif //OGS_USE_EIGEN
-
-
diff --git a/Tests/NumLib/CoordinatesMappingTestData/TestLine2.h b/Tests/NumLib/CoordinatesMappingTestData/TestLine2.h
index 9ddd9f15997..a9ec867d8eb 100644
--- a/Tests/NumLib/CoordinatesMappingTestData/TestLine2.h
+++ b/Tests/NumLib/CoordinatesMappingTestData/TestLine2.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef COORDINATESMAPPINGTESTDATA_TESTLINE2_H_
-#define COORDINATESMAPPINGTESTDATA_TESTLINE2_H_
+#pragma once
 
 #include "MeshLib/Elements/Line.h"
 #include "NumLib/Fem/ShapeFunction/ShapeLine2.h"
@@ -99,5 +98,3 @@ const double TestLine2::cl_exp_detJ = -1;
 const double TestLine2::ze_exp_J[dim*dim] = {0.0};
 
 }
-
-#endif
diff --git a/Tests/NumLib/CoordinatesMappingTestData/TestLine3.h b/Tests/NumLib/CoordinatesMappingTestData/TestLine3.h
index 594cdceb64a..f15a1c8ce48 100644
--- a/Tests/NumLib/CoordinatesMappingTestData/TestLine3.h
+++ b/Tests/NumLib/CoordinatesMappingTestData/TestLine3.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef COORDINATESMAPPINGTESTDATA_TESTLINE3_H_
-#define COORDINATESMAPPINGTESTDATA_TESTLINE3_H_
+#pragma once
 
 #include "MeshLib/Elements/Line.h"
 #include "NumLib/Fem/ShapeFunction/ShapeLine3.h"
@@ -102,5 +101,3 @@ const double TestLine3::cl_exp_J[dim * dim] = {-1.};
 const double TestLine3::cl_exp_detJ = -1;
 const double TestLine3::ze_exp_J[dim * dim] = {0.0};
 }
-
-#endif
diff --git a/Tests/NumLib/CoordinatesMappingTestData/TestQuad4.h b/Tests/NumLib/CoordinatesMappingTestData/TestQuad4.h
index 654a15152fd..2e66f0f8d7b 100644
--- a/Tests/NumLib/CoordinatesMappingTestData/TestQuad4.h
+++ b/Tests/NumLib/CoordinatesMappingTestData/TestQuad4.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef COORDINATESMAPPINGTESTDATA_TESTQUAD4_H_
-#define COORDINATESMAPPINGTESTDATA_TESTQUAD4_H_
+#pragma once
 
 #include "MeshLib/Elements/Quad.h"
 #include "NumLib/Fem/ShapeFunction/ShapeQuad4.h"
@@ -101,6 +100,3 @@ const double TestQuad4::cl_exp_detJ = -1.;
 const double TestQuad4::ze_exp_J[dim*dim] = {1.0, 0.0, 0.0, 0.0};
 
 }
-
-#endif
-
diff --git a/Tests/NumLib/CoordinatesMappingTestData/TestTri3.h b/Tests/NumLib/CoordinatesMappingTestData/TestTri3.h
index 793b01e8c36..84269f1a474 100644
--- a/Tests/NumLib/CoordinatesMappingTestData/TestTri3.h
+++ b/Tests/NumLib/CoordinatesMappingTestData/TestTri3.h
@@ -6,8 +6,7 @@
  *              http://www.opengeosys.org/LICENSE.txt
  */
 
-#ifndef COORDINATESMAPPINGTESTDATA_TESTTRI3_H_
-#define COORDINATESMAPPINGTESTDATA_TESTTRI3_H_
+#pragma once
 
 #include "MeshLib/Elements/Tri.h"
 #include "NumLib/Fem/ShapeFunction/ShapeTri3.h"
@@ -96,5 +95,3 @@ const double TestTri3::cl_exp_detJ = -1.;
 const double TestTri3::ze_exp_J[dim*dim] = {1.0, 0.0, 1.0, 0.0};
 
 }
-
-#endif
diff --git a/Tests/NumLib/FeTestData/MatrixTools.h b/Tests/NumLib/FeTestData/MatrixTools.h
index a623ca68de4..ebe4e449dae 100644
--- a/Tests/NumLib/FeTestData/MatrixTools.h
+++ b/Tests/NumLib/FeTestData/MatrixTools.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TEST_MATRIXTOOLS_H_
-#define TEST_MATRIXTOOLS_H_
+#pragma once
 
 namespace FeTestData
 {
@@ -34,6 +33,3 @@ inline void setIdentityMatrix(unsigned dim, T_MATRIX &m)
 }
 
 } // namespace
-
-#endif
-
diff --git a/Tests/NumLib/FeTestData/TestFeHEX8.h b/Tests/NumLib/FeTestData/TestFeHEX8.h
index 77af05feadf..1792de0bd46 100644
--- a/Tests/NumLib/FeTestData/TestFeHEX8.h
+++ b/Tests/NumLib/FeTestData/TestFeHEX8.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TESTFEHEX8_H_
-#define TESTFEHEX8_H_
+#pragma once
 
 #include "MeshLib/Elements/Hex.h"
 #include "NumLib/Fem/FiniteElement/C0IsoparametricElements.h"
@@ -89,6 +88,3 @@ public:
 };
 
 } // namespace
-
-#endif
-
diff --git a/Tests/NumLib/FeTestData/TestFeLINE2.h b/Tests/NumLib/FeTestData/TestFeLINE2.h
index 7d5d806ae71..b921646dcfa 100644
--- a/Tests/NumLib/FeTestData/TestFeLINE2.h
+++ b/Tests/NumLib/FeTestData/TestFeLINE2.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TESTFELINE2_H_
-#define TESTFELINE2_H_
+#pragma once
 
 #include "MeshLib/Elements/Line.h"
 #include "NumLib/Fem/FiniteElement/C0IsoparametricElements.h"
@@ -69,6 +68,3 @@ public:
 };
 
 } // namespace
-
-#endif
-
diff --git a/Tests/NumLib/FeTestData/TestFeLINE2Y.h b/Tests/NumLib/FeTestData/TestFeLINE2Y.h
index 0971ad6d59d..31e7c8a2dcc 100644
--- a/Tests/NumLib/FeTestData/TestFeLINE2Y.h
+++ b/Tests/NumLib/FeTestData/TestFeLINE2Y.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TESTFELINE2Y_H_
-#define TESTFELINE2Y_H_
+#pragma once
 
 #include "MeshLib/Elements/Line.h"
 #include "NumLib/Fem/FiniteElement/C0IsoparametricElements.h"
@@ -68,6 +67,3 @@ public:
 };
 
 } // namespace
-
-#endif
-
diff --git a/Tests/NumLib/FeTestData/TestFeLINE3.h b/Tests/NumLib/FeTestData/TestFeLINE3.h
index 614c2478dc2..7c396003c11 100644
--- a/Tests/NumLib/FeTestData/TestFeLINE3.h
+++ b/Tests/NumLib/FeTestData/TestFeLINE3.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TESTFELINE3_H_
-#define TESTFELINE3_H_
+#pragma once
 
 #include "MeshLib/Elements/Line.h"
 #include "NumLib/Fem/FiniteElement/C0IsoparametricElements.h"
@@ -71,6 +70,3 @@ public:
 };
 
 } // namespace
-
-#endif
-
diff --git a/Tests/NumLib/FeTestData/TestFePRISM6.h b/Tests/NumLib/FeTestData/TestFePRISM6.h
index 6c5492a20b3..114ff74de3d 100644
--- a/Tests/NumLib/FeTestData/TestFePRISM6.h
+++ b/Tests/NumLib/FeTestData/TestFePRISM6.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TESTFEPRISM6_H_
-#define TESTFEPRISM6_H_
+#pragma once
 
 #include "MeshLib/Elements/Prism.h"
 #include "NumLib/Fem/FiniteElement/C0IsoparametricElements.h"
@@ -82,6 +81,3 @@ public:
 };
 
 } // namespace
-
-#endif
-
diff --git a/Tests/NumLib/FeTestData/TestFePYRA5.h b/Tests/NumLib/FeTestData/TestFePYRA5.h
index a759d7b1419..05c6b34b944 100644
--- a/Tests/NumLib/FeTestData/TestFePYRA5.h
+++ b/Tests/NumLib/FeTestData/TestFePYRA5.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TESTFEPYRA5_H_
-#define TESTFEPYRA5_H_
+#pragma once
 
 #include "MeshLib/Elements/Pyramid.h"
 #include "NumLib/Fem/FiniteElement/C0IsoparametricElements.h"
@@ -78,6 +77,3 @@ public:
 };
 
 } // namespace
-
-#endif
-
diff --git a/Tests/NumLib/FeTestData/TestFeQUAD4.h b/Tests/NumLib/FeTestData/TestFeQUAD4.h
index aca8e53d163..f67805edfe6 100644
--- a/Tests/NumLib/FeTestData/TestFeQUAD4.h
+++ b/Tests/NumLib/FeTestData/TestFeQUAD4.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TESTFEQUAD4_H_
-#define TESTFEQUAD4_H_
+#pragma once
 
 #include "MeshLib/Elements/Quad.h"
 #include "NumLib/Fem/FiniteElement/C0IsoparametricElements.h"
@@ -77,6 +76,3 @@ public:
 };
 
 } // namespace
-
-#endif
-
diff --git a/Tests/NumLib/FeTestData/TestFeTET4.h b/Tests/NumLib/FeTestData/TestFeTET4.h
index b7c9266ba22..36a58ab0d6b 100644
--- a/Tests/NumLib/FeTestData/TestFeTET4.h
+++ b/Tests/NumLib/FeTestData/TestFeTET4.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TESTFETET4_H_
-#define TESTFETET4_H_
+#pragma once
 
 #include "MeshLib/Elements/Tet.h"
 #include "NumLib/Fem/FiniteElement/C0IsoparametricElements.h"
@@ -75,6 +74,3 @@ public:
 };
 
 } // namespace
-
-#endif
-
diff --git a/Tests/NumLib/FeTestData/TestFeTRI3.h b/Tests/NumLib/FeTestData/TestFeTRI3.h
index 5eb1763d262..c118ba23ea5 100644
--- a/Tests/NumLib/FeTestData/TestFeTRI3.h
+++ b/Tests/NumLib/FeTestData/TestFeTRI3.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TESTFETRI3_H_
-#define TESTFETRI3_H_
+#pragma once
 
 #include "MeshLib/Elements/Tri.h"
 #include "NumLib/Fem/FiniteElement/C0IsoparametricElements.h"
@@ -73,6 +72,3 @@ public:
 };
 
 } // namespace
-
-#endif
-
diff --git a/Tests/NumLib/ODEs.h b/Tests/NumLib/ODEs.h
index ac083d0cb94..848b62cda93 100644
--- a/Tests/NumLib/ODEs.h
+++ b/Tests/NumLib/ODEs.h
@@ -7,8 +7,7 @@
  *
  */
 
-#ifndef TESTS_NUMLIB_ODES_H
-#define TESTS_NUMLIB_ODES_H
+#pragma once
 
 #include <boost/math/constants/constants.hpp>
 #include "MathLib/LinAlg/LinAlg.h"
@@ -300,5 +299,3 @@ const double ODETraits<ODE3>::t0 = 0.0;
 const double ODETraits<ODE3>::t_end =
     0.5 * boost::math::constants::pi<double>();
 // ODE 3 end //////////////////////////////////////////////////////
-
-#endif // TESTS_NUMLIB_ODES_H
diff --git a/Tests/NumLib/SteadyDiffusion2DExample1.h b/Tests/NumLib/SteadyDiffusion2DExample1.h
index 0c924b62e9a..909e515e9f6 100644
--- a/Tests/NumLib/SteadyDiffusion2DExample1.h
+++ b/Tests/NumLib/SteadyDiffusion2DExample1.h
@@ -10,8 +10,7 @@
  *
  */
 
-#ifndef STEADYDIFFUSION2DEXAMPLE1_H_
-#define STEADYDIFFUSION2DEXAMPLE1_H_
+#pragma once
 
 #include <cmath>
 #include <vector>
@@ -149,6 +148,3 @@ template<typename IndexType>struct SteadyDiffusion2DExample1
     LocalMatrixType _localA;
     LocalVectorType _localRhs;
 };
-
-
-#endif //STEADYDIFFUSION2DEXAMPLE1_H_
diff --git a/Tests/NumLib/TimeSteppingTestingTools.h b/Tests/NumLib/TimeSteppingTestingTools.h
index b2fe2766f06..0922d246883 100644
--- a/Tests/NumLib/TimeSteppingTestingTools.h
+++ b/Tests/NumLib/TimeSteppingTestingTools.h
@@ -9,8 +9,7 @@
  *              http://www.opengeosys.org/project/license
  */
 
-#ifndef TIMESTEPPINGTESTINGTOOLS_H_
-#define TIMESTEPPINGTESTINGTOOLS_H_
+#pragma once
 
 #include <logog/include/logog.hpp>
 
@@ -47,5 +46,3 @@ std::vector<double> timeStepping(T_TIME_STEPPING &algorithm, T* obj=nullptr)
     return vec_t;
 }
 } // namespace
-
-#endif // TIMESTEPPINGTESTINGTOOLS_H_
diff --git a/Tests/TestTools.h b/Tests/TestTools.h
index ee61d1060f2..42a8e309c4a 100644
--- a/Tests/TestTools.h
+++ b/Tests/TestTools.h
@@ -15,8 +15,7 @@
 #include <gtest/gtest.h>
 #include <boost/property_tree/ptree_fwd.hpp>
 
-#ifndef TESTTOOLS_H_
-#define TESTTOOLS_H_
+#pragma once
 
 #define ASSERT_ARRAY_NEAR(E,A,N,eps)\
     for (std::size_t i=0; i<(unsigned)(N); i++) \
@@ -28,5 +27,3 @@
 
 boost::property_tree::ptree
 readXml(const char xml[]);
-
-#endif // TESTTOOLS_H_
-- 
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