diff --git a/Makefile b/Makefile
index d7825aa..9c4c435 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-packages = $(shell basename --suffix=.spec specs/*/*.spec)
+packages = $(shell basename -s .spec specs/*/*.spec)
 checkout_packages = $(patsubst %, checkout-%, $(packages))
 build_packages = $(patsubst %, build-%, $(packages))
 
--
libgit2 0.21.2