diff --git a/piptools/scripts/compile.py b/piptools/scripts/compile.py
index 0638337f9..22d513649 100755
--- a/piptools/scripts/compile.py
+++ b/piptools/scripts/compile.py
@@ -433,7 +433,7 @@ def cli(
         # We explicitly set extra=None to filter out optional requirements
         # since evaluating an extra marker with no environment raises UndefinedEnvironmentName
         # (see https://packaging.pypa.io/en/latest/markers.html#usage)
-        or req.markers.evaluate(dict(extra=None))
+        or req.markers.evaluate({"extra": None})
     ]
 
     log.debug("Using indexes:")