diff --git a/scripts/ci/jobs/build-guix.yml b/scripts/ci/jobs/build-guix.yml
index 45dcb7771a8eb80453e4392b9b5d73f84a2dd040..49e3b8647c07a78923c846d7130df47e3cb49985 100644
--- a/scripts/ci/jobs/build-guix.yml
+++ b/scripts/ci/jobs/build-guix.yml
@@ -50,6 +50,10 @@ deploy container:
       if [[ "$GUIX_PACKAGE" =~ .*-mkl ]]; then
         GUIX_ARGS="--with-commit=eigen=9000b3767770f6dd0f4cfb12f4e19c71921885a4 --without-tests=eigen --with-configure-flag=vtk-9.3=-DVTK_MODULE_USE_EXTERNAL_VTK_eigen=OFF"
       fi
+      # Add openmpi package for mpirun
+      if [[ "$GUIX_PACKAGE" =~ .*petsc.* ]]; then
+        GUIX_ARGS="${GUIX_ARGS} openmpi"
+      fi
     # Build phase, retry once if failed
     - guix time-machine -C scripts/guix/channels.scm -- build bash coreutils
     - if [ $? -ne 0 ]; then !!; fi
@@ -57,7 +61,6 @@ deploy container:
     - if [ $? -ne 0 ]; then !!; fi
     # Pack phase
     - mcli alias set minio https://minio.ufz.de $MINIO_PUBLIC_ACCESS_KEY $MINIO_PUBLIC_SECRET_KEY
-    # Pack serial image
     - image=$( guix time-machine -C scripts/guix/channels.scm -- pack -RR --format=squashfs bash coreutils ${GUIX_PACKAGE} --with-source=${GUIX_PACKAGE}=$PWD ${GUIX_ARGS} | tee | tail -1 )
     - echo "Image (${GUIX_PACKAGE}) $image"
     - mcli cp $image minio/ogs/public/container/ogs/master/${GUIX_PACKAGE}.squashfs