Only install Haskell world on systems where it is necessary.

home-manager/machines.nix

@@ -64,7 +64,7 @@ let
         ./roles/git-sign.nix
         ./roles/gnome.nix
         ./roles/status-script.nix
-        ./roles/hoogle.nix
+        ./roles/haskell-env.nix
         ./roles/terminal.nix
         ./roles/mpclient.nix
         ./roles/mpd.nix

home-manager/roles/default.nix

@@ -146,7 +146,6 @@
           magic-wormhole
           alejandra
           nix-top
-          ghcWithPackages
           ghcid
           matrix-commander
           upterm

home-manager/roles/haskell-env.nix

@@ -7,4 +7,5 @@
       Restart = "always";
     };
   };
+  home.packages = [pkgs.ghcWithPackages];
 }

overlays/ghc/default.nix

@@ -1,7 +1,6 @@
 final: _: let
   myPkgs = import ./packages.nix;
 in {
-  myHaskellPackages = myPkgs.makeHaskellPackages final.unstableHaskellPackages;
   myHaskellScriptPackages = myPkgs.makeHaskellScriptPackages final.haskellPackages;
-  ghcWithPackages = final.unstableGhc.withHoogle (p: builtins.attrValues (myPkgs.makeHaskellPackages p));
+  ghcWithPackages = final.unstableGhc.withHoogle (p: builtins.attrValues (myPkgs.makeHaskellPackages p // (final.flake-inputs.self.overlays.addMyHaskellPackages "" "")));
 }

packages/.envrc

@@ -1 +0,0 @@
-use flake ..#haskell

packages/flake-module.nix

@@ -86,13 +86,5 @@ in {
   };
   perSystem = {config, ...}: {
     inherit packages;
-    devShells.haskell = hpkgs.shellFor {
-      packages = hpkgs: (builtins.attrValues (selectHaskellPackages hpkgs));
-      shellHook = config.pre-commit.installationScript;
-      buildInputs = [
-        hpkgs.haskell-language-server
-        hpkgs.cabal-install
-      ];
-    };
   };
 }