Add release.nix

default.nix

@@ -1,5 +1,5 @@
-{ python }:
+{ pkgs ? (import <nixpkgs> {}) }:
-with python.pkgs;
+with pkgs.python3Packages;
 buildPythonPackage rec {
   name = "mqtt-dash";
   src = ./.;

release.nix

@@ -5,5 +5,8 @@
       let
         pkgs = import <nixpkgs> { inherit system; };
       in
-        pkgs.callPackage ./. { python = pkgs.python3; };
+        pkgs.releaseTools.nixBuild {
+          name = "mqtt-dash";
+          src = <mqtt-dash-src>;
+        };
 }