diff --git a/gnu/packages/backup.scm b/gnu/packages/backup.scm
index 35cd3cf7f3..c8382536b0 100644
--- a/gnu/packages/backup.scm
+++ b/gnu/packages/backup.scm
@@ -588,6 +588,8 @@ (define-public borg
            ;; generate the wrong list.
            (for-each delete-file
                      '("src/borg/algorithms/checksums.c"
+                       "src/borg/algorithms/msgpack/_packer.cpp"
+                       "src/borg/algorithms/msgpack/_unpacker.cpp"
                        "src/borg/chunker.c"
                        "src/borg/compress.c"
                        "src/borg/crypto/low_level.c"