diff --git a/grouptools/GNUmakefile b/grouptools/GNUmakefile
index 2f4c690..dc76e68 100644
--- a/grouptools/GNUmakefile
+++ b/grouptools/GNUmakefile
@@ -28,4 +28,9 @@ configure: $(CONFDIR)/start $(CONFDIR)/perl $(CONFDIR)/finish
 
 endif
 
+GNUmakevars: GNUmakevars.sh
+	sh ./$^ > $@
+GNUmakerules: GNUmakerules.sh
+	sh ./$^ > $@
+
 include GNUmakerules
diff --git a/grouptools/GNUmakerules.sh b/grouptools/GNUmakerules.sh
new file mode 100644
index 0000000..e523b37
--- /dev/null
+++ b/grouptools/GNUmakerules.sh
@@ -0,0 +1,3 @@
+#!/bin/sh
+echo "\$(BINDIR)/%: %"
+echo -e "\tcp \$^ \$@"
diff --git a/grouptools/GNUmakevars.sh b/grouptools/GNUmakevars.sh
new file mode 100644
index 0000000..a7de4ae
--- /dev/null
+++ b/grouptools/GNUmakevars.sh
@@ -0,0 +1,5 @@
+#!/bin/sh
+prefix=${prefix:-/usr/local}
+echo "BINDIR=$prefix/bin"
+echo
+echo "all:"