diff --git a/Makefile b/Makefile
index 1b9348a..548ee65 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,5 @@
 all:
 
 tag:
-	test -z "`git status -s quicklisp.lisp`"
-	git tag version-`grep 'defvar qlqs-info:.version.' quicklisp.lisp | cut -d\" -f 2`
+	test -z "$(git status -s quicklisp.lisp)"
+	git tag version-$(grep -Eohm1 2[0-9-]{9} quicklisp.lisp)