diff --git a/Makefile b/Makefile
index d05d4a3..dc90ac7 100644
--- a/Makefile
+++ b/Makefile
@@ -86,10 +86,9 @@ $(lw_source_tarball) : $(lw_source_dir)
 	touch $(lw_source_dir)
 	sha256sum $(lw_source_tarball) > $(lw_source_tarball).sha256sum
 	cat $(lw_source_tarball).sha256sum
-
-
-
-
+	[ "$(SIGNING_KEY)" != "" ] && cp -v $(SIGNING_KEY) pk.asc ; true
+	if [[ -f pk.asc ]]; then gpg --import pk.asc; gpg --detach-sign $(lw_source_tarball); fi
+	ls -lh $(lw_source_tarball).sig
 
 
 debs=python3 python3-dev python3-pip