diff --git a/buildbot_nix/__init__.py b/buildbot_nix/__init__.py
index 851b97a..1cb5744 100644
--- a/buildbot_nix/__init__.py
+++ b/buildbot_nix/__init__.py
@@ -460,7 +460,7 @@ def make_job_evaluator(name: str, settings: EvaluatorSettings, flake: bool) -> N
     if flake:
         actual_command += ["--flake", f".#{FLAKE_TARGET_ATTRIBUTE_FOR_JOBS}"]
     else:
-        actual_command += ["--expr", "'import ./.ci/buildbot.nix'"]
+        actual_command += ["--expr", "import ./.ci/buildbot.nix"]
 
     return NixEvalCommand(
         env={},