chore: add nix flake

.gitignore

@@ -1,2 +1,3 @@
 node_modules
 dist
+result

flake.nix

@@ -0,0 +1,57 @@
+{
+  description = "A Gnome extension to mimic macOS's Rectangle tiling.";
+
+  inputs = {
+    nixpkgs.url = github:NixOS/nixpkgs/nixpkgs-unstable;
+    flake-utils.url = github:numtide/flake-utils;
+
+    gitignore.url = "github:hercules-ci/gitignore.nix";
+    gitignore.inputs.nixpkgs.follows = "nixpkgs";
+  };
+
+  outputs = { self, nixpkgs, flake-utils, gitignore }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        inherit (gitignore.lib) gitignoreSource;
+        pkgs = (import nixpkgs) { inherit system; };
+        nodejs = pkgs.nodejs;
+        node2nixOutput = import ./nix { inherit pkgs nodejs system; };
+        nodeDeps = node2nixOutput.nodeDependencies;
+        buildDependencies = with pkgs; [
+          busybox
+          glib
+          nodejs
+          typescript
+          zip
+        ];
+      in
+      {
+        formatter = nixpkgs.legacyPackages.${system}.nixpkgs-fmt;
+        packages.default = pkgs.stdenv.mkDerivation {
+          name = "gnome-extensions-rectangle";
+          version = "master";
+          src = gitignoreSource ./.;
+          nativeBuildInputs = buildDependencies;
+          dontCheck = true;
+          dontConfigure = true;
+          dontFixup = true;
+          buildPhase = ''
+            runHook preBuild
+            ln -sf ${nodeDeps}/lib/node_modules ./node_modules
+            make pack
+            runHook postBuild
+          '';
+          installPhase = ''
+            runHook preInstall
+            mkdir -p $out/share/gnome-shell/extensions/[email protected]
+            unzip rectangle.zip -d $out/share/gnome-shell/extensions/[email protected]
+            cp rectangle.zip $out/
+            runHook postInstall
+          '';
+        };
+        devShell = pkgs.mkShell {
+          packages = buildDependencies;
+        };
+      }
+    );
+}

nix/default.nix

@@ -0,0 +1,17 @@
+# This file has been generated by node2nix 1.11.1. Do not edit!
+
+{pkgs ? import <nixpkgs> {
+    inherit system;
+  }, system ? builtins.currentSystem, nodejs ? pkgs."nodejs-14_x"}:
+
+let
+  nodeEnv = import ./node-env.nix {
+    inherit (pkgs) stdenv lib python2 runCommand writeTextFile writeShellScript;
+    inherit pkgs nodejs;
+    libtool = if pkgs.stdenv.isDarwin then pkgs.darwin.cctools else null;
+  };
+in
+import ./node-package.nix {
+  inherit (pkgs) fetchurl nix-gitignore stdenv lib fetchgit;
+  inherit nodeEnv;
+}