Merge pull request #2 from srid/srid/issue1

flake.nix

@@ -14,6 +14,21 @@
         overlays = [ ];
         pkgs =
           import nixpkgs { inherit system overlays; config.allowBroken = true; };
+        # https://github.com/NixOS/nixpkgs/issues/140774#issuecomment-976899227
+        m1MacHsBuildTools =
+          pkgs.haskellPackages.override {
+            overrides = self: super:
+              let
+                workaround140774 = hpkg: with pkgs.haskell.lib;
+                  overrideCabal hpkg (drv: {
+                    enableSeparateBinOutput = false;
+                  });
+              in
+              {
+                ghcid = workaround140774 super.ghcid;
+                ormolu = workaround140774 super.ormolu;
+              };
+          };
         project = returnShellEnv:
           pkgs.haskellPackages.developPackage {
             inherit returnShellEnv;
@@ -25,8 +40,10 @@
               # cf. https://tek.brick.do/K3VXJd8mEKO7
             };
             modifier = drv:
-              pkgs.haskell.lib.addBuildTools drv (with pkgs.haskellPackages;
+              pkgs.haskell.lib.addBuildTools drv
-              [
+                (with (if system == "aarch64-darwin"
+                then m1MacHsBuildTools
+                else pkgs.haskellPackages); [
                   # Specify your build/dev dependencies here. 
                   cabal-fmt
                   cabal-install