Initial test commit

nix-modpack/lib/default.nix

@@ -0,0 +1,33 @@
+{ nix-minecraft, ... }:
+
+let
+  mkModpack =
+    { inputs }:
+    let
+      nixpkgs = inputs.nixpkgs;
+      lib = nixpkgs.lib;
+
+      eachSystem =
+        fn: lib.genAttrs lib.systems.flakeExposed (system: fn (import nixpkgs { inherit system; }));
+
+      mkPackages = pkgs: {
+        modpack = nix-minecraft.legacyPackages.${pkgs.system}.fetchPackwizModpack {
+          url = inputs.self;
+        };
+      };
+
+      overlay = final: prev: mkPackages prev;
+    in
+    {
+      inherit overlay;
+      packages = eachSystem mkPackages;
+      devShells = eachSystem (pkgs: {
+        default = pkgs.mkShell {
+          buildInputs = with pkgs; [
+            packwiz
+          ];
+        };
+      });
+    };
+in
+mkModpack