diff --git a/gnu/packages/bioinformatics.scm b/gnu/packages/bioinformatics.scm
index 2b7f78be342f5a51c1f967e3cd72558053f7170d..a28832dfa87c78a4e52f3ec26ace36fc6b42a4ea 100644
--- a/gnu/packages/bioinformatics.scm
+++ b/gnu/packages/bioinformatics.scm
@@ -2115,7 +2115,7 @@ (define-public preseq
             (chdir "preseq-master")
             #t))
          (add-after
-          'unpack 'use-samtools-headers
+          'enter-dir 'use-samtools-headers
           (lambda _
             (substitute* '("smithlab_cpp/SAM.cpp"
                            "smithlab_cpp/SAM.hpp")