diff --git a/pkgs/development/python-modules/avwx-engine/default.nix b/pkgs/development/python-modules/avwx-engine/default.nix
index 6195e09b5b8e..25876499a5bf 100644
--- a/pkgs/development/python-modules/avwx-engine/default.nix
+++ b/pkgs/development/python-modules/avwx-engine/default.nix
@@ -17,7 +17,7 @@
   xmltodict,
 }:
 
-buildPythonPackage rec {
+buildPythonPackage (finalAttrs: {
   pname = "avwx-engine";
   version = "1.9.8";
   pyproject = true;
@@ -25,7 +25,7 @@ buildPythonPackage rec {
   src = fetchFromGitHub {
     owner = "avwx-rest";
     repo = "avwx-engine";
-    tag = version;
+    tag = finalAttrs.version;
     hash = "sha256-RJOXMbbBdcuWvNcQUGq5VHCpdWOVQoBjruQ96m1f1gc=";
   };
 
@@ -59,7 +59,7 @@ buildPythonPackage rec {
     pytestCheckHook
     time-machine
   ]
-  ++ lib.concatAttrValues optional-dependencies;
+  ++ lib.flatten (builtins.attrValues finalAttrs.passthru.optional-dependencies);
 
   pythonImportsCheck = [ "avwx" ];
 
@@ -73,8 +73,8 @@ buildPythonPackage rec {
   meta = {
     description = "Aviation Weather parsing engine";
     homepage = "https://github.com/avwx-rest/avwx-engine";
-    changelog = "https://github.com/avwx-rest/avwx-engine/blob/${src.tag}/changelog.md";
+    changelog = "https://github.com/avwx-rest/avwx-engine/blob/${finalAttrs.src.tag}/changelog.md";
     license = lib.licenses.mit;
     maintainers = with lib.maintainers; [ fab ];
   };
-}
+})