diff --git a/pkgs/development/python-modules/http-parser/default.nix b/pkgs/development/python-modules/http-parser/default.nix
index d0fc242c9896..1ca7c73ef2f2 100644
--- a/pkgs/development/python-modules/http-parser/default.nix
+++ b/pkgs/development/python-modules/http-parser/default.nix
@@ -19,9 +19,14 @@ buildPythonPackage rec {
   };
 
   nativeBuildInputs = [
+    cython
     setuptools
   ];
 
+  preBuild = ''
+    # re-run cython
+    make -B
+  '';
 
   pythonImportsCheck = [
     "http_parser"