use flake-utils.eachSystem

Author: wavewave

flake.lock

@@ -1,48 +1,55 @@
 {
   description = "concat";
-  inputs = { nixpkgs.url = "github:NixOS/nixpkgs/nixos-21.11"; };
-  outputs = { self, nixpkgs }:
-    let
-      pkgs = nixpkgs.legacyPackages.x86_64-linux;
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-21.11";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+  outputs = { self, nixpkgs, flake-utils }:
+    flake-utils.lib.eachSystem [ "x86_64-linux" "x86_64-darwin" ] (system:
+      let
+        pkgs = import nixpkgs { inherit system; };
 
-      haskellOverlay = self: super: {
-        "concat-inline" = pkgs.haskell.lib.dontHaddock
-          (self.callCabal2nix "concat-inline" ./inline { });
-        "concat-plugin" = self.callCabal2nix "concat-plugin" ./plugin { };
-        "concat-classes" = self.callCabal2nix "concat-classes" ./classes { };
-        "concat-satisfy" = self.callCabal2nix "concat-satisfy" ./satisfy { };
-        "concat-known" = self.callCabal2nix "concat-known" ./known { };
-        #"concat-hardware" = self.callCabal2nix "concat-hardware" ./hardware { };
-        "concat-graphics" = self.callCabal2nix "concat-graphics" ./graphics { };
-        "concat-examples" = pkgs.haskell.lib.dontHaddock
-          (self.callCabal2nix "concat-examples" ./examples { });
-      };
+        haskellOverlay = self: super: {
+          "concat-inline" = pkgs.haskell.lib.dontHaddock
+            (self.callCabal2nix "concat-inline" ./inline { });
+          "concat-plugin" = self.callCabal2nix "concat-plugin" ./plugin { };
+          "concat-classes" = self.callCabal2nix "concat-classes" ./classes { };
+          "concat-satisfy" = self.callCabal2nix "concat-satisfy" ./satisfy { };
+          "concat-known" = self.callCabal2nix "concat-known" ./known { };
+          #"concat-hardware" = self.callCabal2nix "concat-hardware" ./hardware { };
+          "concat-graphics" =
+            self.callCabal2nix "concat-graphics" ./graphics { };
+          "concat-examples" = pkgs.haskell.lib.dontHaddock
+            (self.callCabal2nix "concat-examples" ./examples { });
+        };
 
-      newHaskellPackages =
-        pkgs.haskellPackages.override { overrides = haskellOverlay; };
+        newHaskellPackages =
+          pkgs.haskellPackages.override { overrides = haskellOverlay; };
 
-    in {
-      packages.x86_64-linux = {
-        inherit (newHaskellPackages)
-          concat-inline concat-plugin concat-classes concat-satisfy concat-known
-          #concat-hardware
-          concat-graphics concat-examples;
-      };
+      in {
+        packages = {
+          inherit (newHaskellPackages)
+            concat-inline concat-plugin concat-classes concat-satisfy
+            concat-known
+            #concat-hardware
+            concat-graphics concat-examples;
+        };
 
-      # see these issues and discussions:
-      # - https://github.com/NixOS/nixpkgs/issues/16394
-      # - https://github.com/NixOS/nixpkgs/issues/25887
-      # - https://github.com/NixOS/nixpkgs/issues/26561
-      # - https://discourse.nixos.org/t/nix-haskell-development-2020/6170
-      overlay = final: prev: {
-        haskellPackages = prev.haskellPackages.override (old: {
-          overrides = final.lib.composeExtensions (old.overrides or (_: _: { }))
-            haskellOverlay;
-        });
-      };
+        # see these issues and discussions:
+        # - https://github.com/NixOS/nixpkgs/issues/16394
+        # - https://github.com/NixOS/nixpkgs/issues/25887
+        # - https://github.com/NixOS/nixpkgs/issues/26561
+        # - https://discourse.nixos.org/t/nix-haskell-development-2020/6170
+        overlay = final: prev: {
+          haskellPackages = prev.haskellPackages.override (old: {
+            overrides =
+              final.lib.composeExtensions (old.overrides or (_: _: { }))
+              haskellOverlay;
+          });
+        };
 
-      devShell.x86_64-linux = let
-        hsenv = pkgs.haskellPackages.ghcWithPackages (p: [ p.cabal-install ]);
-      in pkgs.mkShell { buildInputs = [ hsenv ]; };
-    };
+        devShell = let
+          hsenv = pkgs.haskellPackages.ghcWithPackages (p: [ p.cabal-install ]);
+        in pkgs.mkShell { buildInputs = [ hsenv ]; };
+      });
 }