nix: apply a source filter to the main package

Signed-off-by: NotAShelf <raf@notashelf.dev>
Change-Id: Id6933272a05f17c70fe91719dbd3ac9c6a6a6964

nix/package.nix

@@ -5,14 +5,23 @@
   raylib,
   pkg-config,
 }:
-stdenv.mkDerivation (finalAttrs: {
+stdenv.mkDerivation {
   pname = "rogged";
   version = "0.0.1";
 
-  src = builtins.path {
-    path = ../.;
-    name = finalAttrs.pname;
-  };
+  src = let
+    fs = lib.fileset;
+    s = ../.;
+  in
+    fs.toSource {
+      root = s;
+      fileset = fs.unions [
+        (s + /assets)
+        (s + /libs)
+        (s + /src)
+        (s + /build.zig)
+      ];
+    };
 
   nativeBuildInputs = [
     zig
@@ -21,25 +30,9 @@ stdenv.mkDerivation (finalAttrs: {
 
   buildInputs = [raylib];
 
-  dontConfigure = true;
-
-  buildPhase = ''
-    runHook preBuild
-    export ZIG_GLOBAL_CACHE_DIR="$TMPDIR/zig-cache"
-    zig build --release=fast
-    runHook postBuild
-  '';
-
-  installPhase = ''
-    runHook preInstall
-    mkdir -p $out/bin
-    cp zig-out/bin/roguelike $out/bin/
-    runHook postInstall
-  '';
-
   meta = {
     description = "A turn-based roguelike game";
     license = lib.licenses.mit;
     mainProgram = "roguelike";
   };
-})
+}