diff --git a/rules/common.smk b/rules/common.smk
index 50132f4b..598d3b98 100644
--- a/rules/common.smk
+++ b/rules/common.smk
@@ -4,8 +4,8 @@
 
 import os, sys, glob
 
-for path in ["../scripts", "./scripts"]:
-    sys.path.insert(0, os.path.abspath(path)
+path = workflow.source_path("../scripts/_helpers.py")
+sys.path.insert(0, os.path.dirname(path))
 
 from _helpers import validate_checksum