diff --git a/pip_build.py b/pip_build.py
index e42c8debc..f4a56c9b4 100644
--- a/pip_build.py
+++ b/pip_build.py
@@ -16,7 +16,7 @@
 
 
 def ignore_files(_, filenames):
-    return [f for f in filenames if f.endswith("_test.py")]
+    return [f for f in filenames if "test" in f]
 
 
 def build():