diff --git a/pkgs/by-name/pr/pretalx/package.nix b/pkgs/by-name/pr/pretalx/package.nix
index bea6f3cc41c4..9f733eeb8fe4 100644
--- a/pkgs/by-name/pr/pretalx/package.nix
+++ b/pkgs/by-name/pr/pretalx/package.nix
@@ -85,7 +85,9 @@ python.pkgs.buildPythonApplication rec {
   ]);
 
   pythonRelaxDeps = [
+    "cssutils"
     "django-csp"
+    "django-filter"
     "python-dateutil"
   ];