diff --git a/flake.lock b/flake.lock
index ca8c578080..cf736beb1b 100644
--- a/flake.lock
+++ b/flake.lock
@@ -1,5 +1,35 @@
 {
   "nodes": {
+    "flake-utils": {
+      "locked": {
+        "lastModified": 1649676176,
+        "narHash": "sha256-OWKJratjt2RW151VUlJPRALb7OU2S5s+f0vLj4o1bHM=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "a4b154ebbdc88c8498a5c7b01589addc9e9cb678",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "flake-utils_2": {
+      "locked": {
+        "lastModified": 1629481132,
+        "narHash": "sha256-JHgasjPR0/J1J3DRm4KxM4zTyAj4IOJY8vIl75v/kPI=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "997f7efcb746a9c140ce1f13c72263189225f482",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1647282937,
@@ -32,10 +62,47 @@
         "type": "github"
       }
     },
+    "nixpkgs_2": {
+      "locked": {
+        "lastModified": 1631288242,
+        "narHash": "sha256-sXm4KiKs7qSIf5oTAmrlsEvBW193sFj+tKYVirBaXz0=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "0e24c87754430cb6ad2f8c8c8021b29834a8845e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixpkgs-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
     "root": {
       "inputs": {
+        "flake-utils": "flake-utils",
         "nixpkgs": "nixpkgs",
-        "nixpkgs-unstable": "nixpkgs-unstable"
+        "nixpkgs-unstable": "nixpkgs-unstable",
+        "zig": "zig"
+      }
+    },
+    "zig": {
+      "inputs": {
+        "flake-utils": "flake-utils_2",
+        "nixpkgs": "nixpkgs_2"
+      },
+      "locked": {
+        "lastModified": 1650415318,
+        "narHash": "sha256-HZDhiEELVjhZf9pR0Y3cYVFI7SZVCiSc1g3yqvMYdFk=",
+        "owner": "roarkanize",
+        "repo": "zig-overlay",
+        "rev": "da3b287c1d29761e576ad81ac94aed260744d20d",
+        "type": "github"
+      },
+      "original": {
+        "owner": "roarkanize",
+        "repo": "zig-overlay",
+        "type": "github"
       }
     }
   },
diff --git a/flake.nix b/flake.nix
index e660b3656c..527c677247 100644
--- a/flake.nix
+++ b/flake.nix
@@ -4,67 +4,83 @@
   inputs = {
     nixpkgs.url = "github:nixos/nixpkgs/nixos-21.11";
     nixpkgs-unstable = { url = "github:NixOS/nixpkgs/nixpkgs-unstable"; };
-    # zig = { url = "github:roarkanize/zig-overlay"; };
+    zig = { url = "github:roarkanize/zig-overlay"; };
+    flake-utils.url = "github:numtide/flake-utils";
   };
 
-  outputs = { self, nixpkgs, nixpkgs-unstable }:
-    let
-      pkgs = nixpkgs.legacyPackages.x86_64-linux;
-      unstable-pkgs = nixpkgs-unstable.legacyPackages.x86_64-linux;
-      llvmPkgs = pkgs.llvmPackages_12;
+  outputs = { self, nixpkgs, nixpkgs-unstable, zig, flake-utils }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+        unstable-pkgs = nixpkgs-unstable.legacyPackages.${system};
+        llvmPkgs = pkgs.llvmPackages_12;
 
-      linuxInputs = with pkgs; [
-        valgrind # used in cli tests, see cli/tests/cli_run.rs
-        vulkan-headers
-        vulkan-loader
-        vulkan-tools
-        vulkan-validation-layers
-        xorg.libX11
-        xorg.libXcursor
-        xorg.libXrandr
-        xorg.libXi
-        xorg.libxcb
-        alsa-lib
-      ];
+        linuxInputs = with pkgs;
+          lib.optionals stdenv.isLinux [
+            valgrind # used in cli tests, see cli/tests/cli_run.rs
+            vulkan-headers
+            vulkan-loader
+            vulkan-tools
+            vulkan-validation-layers
+            xorg.libX11
+            xorg.libXcursor
+            xorg.libXrandr
+            xorg.libXi
+            xorg.libxcb
+            alsa-lib
+          ];
 
-      sharedInputs = (with pkgs; [
-        # build libraries
-        cmake
-        git
-        python3
-        llvmPkgs.llvm.dev
-        llvmPkgs.clang
-        libxkbcommon
-        pkg-config
-        zig # roc builtins are implemented in zig, see compiler/builtins/bitcode/
-
-        # lib deps
-        libffi
-        libxml2
-        ncurses
-        zlib
-        libiconv
-
-        # faster builds - see https://github.com/rtfeldman/roc/blob/trunk/BUILDING_FROM_SOURCE.md#use-lld-for-the-linker
-        llvmPkgs.lld
-        # debugir
-      ]) ++ (with unstable-pkgs; [
-        rustc
-        cargo
-        clippy
-        rustfmt
+        darwinInputs = with pkgs;
+          lib.optionals stdenv.isDarwin (with pkgs.darwin.apple_sdk.frameworks; [
+            AppKit
+            CoreFoundation
+            CoreServices
+            CoreVideo
+            Foundation
+            Metal
+            Security
       ]);
-    in {
 
-      devShell.x86_64-linux = pkgs.mkShell {
-        buildInputs = sharedInputs ++ linuxInputs;
+        # zig 0.8.1 from pkgs is broken on aarch64-darwin, hence the workaround
+        zig-toolchain = zig.packages.${system}."0.8.1";
 
-        LLVM_SYS_120_PREFIX = "${llvmPkgs.llvm.dev}";
-        NIX_GLIBC_PATH = if pkgs.stdenv.isLinux then "${pkgs.glibc_multi.out}/lib" else "";
-        LD_LIBRARY_PATH = with pkgs;
-          lib.makeLibraryPath
-          ([ pkg-config stdenv.cc.cc.lib libffi ncurses zlib ] ++ linuxInputs);
-      };
+        sharedInputs = (with pkgs; [
+          # build libraries
+          cmake
+          git
+          python3
+          llvmPkgs.llvm.dev
+          llvmPkgs.clang
+          libxkbcommon
+          pkg-config
+          zig-toolchain # roc builtins are implemented in zig, see compiler/builtins/bitcode/
 
-    };
+          # lib deps
+          libffi
+          libxml2
+          ncurses
+          zlib
+          libiconv
+
+          # faster builds - see https://github.com/rtfeldman/roc/blob/trunk/BUILDING_FROM_SOURCE.md#use-lld-for-the-linker
+          llvmPkgs.lld
+          # debugir
+        ]) ++ (with unstable-pkgs; [
+          rustc
+          cargo
+          clippy
+          rustfmt
+        ]);
+      in {
+        devShell = pkgs.mkShell {
+          buildInputs = sharedInputs ++ darwinInputs ++ linuxInputs;
+
+          LLVM_SYS_120_PREFIX = "${llvmPkgs.llvm.dev}";
+          NIX_GLIBC_PATH = if pkgs.stdenv.isLinux then "${pkgs.glibc_multi.out}/lib" else "";
+          LD_LIBRARY_PATH = with pkgs;
+            lib.makeLibraryPath
+            ([ pkg-config stdenv.cc.cc.lib libffi ncurses zlib ]);
+        };
+      }
+  );  
 }