Testing exact reproducibility revealed the new dependency on findutils since bd86a2db

manifest.scm

 (use-modules ((gnu packages commencement) #:select (gcc-toolchain))
-             ((gnu packages base) #:select (coreutils glibc-locales gnu-make sed))
+             ((gnu packages base) #:select (coreutils findutils glibc-locales gnu-make sed))
              ((gnu packages graphviz) #:select (graphviz))
              ((gnu packages haskell) #:select (ghc))
              ((gnu packages haskell-xyz) #:select (ghc-attoparsec ghc-pandoc pandoc))
@@ -11,6 +11,7 @@
   (concatenate-manifests
     (list (packages->manifest
             (list coreutils
+                  findutils
                   gcc-toolchain
                   ghc
                   ghc-attoparsec