diff --git a/tests/local.mk b/tests/local.mk
index 1ca363091..de095c117 100644
--- a/tests/local.mk
+++ b/tests/local.mk
@@ -42,7 +42,7 @@ nix_tests = \
   build.sh \
   compute-levels.sh \
   ca/build.sh \
-  ca/substitute.sh
+  ca/substitute.sh \
   ca/signatures.sh \
   ca/nix-copy.sh
   # parallel.sh