feat: add Nix flake with dev shell, package, and NixOS/Home Manager modules

Reproducible development environment for NixOS/Nix contributors:
- Dev shell with Node 22, system Electron, Playwright, LD_LIBRARY_PATH
  for X11/Wayland/audio libs, activated automatically via direnv
- buildNpmPackage derivation wrapping system Electron with desktop file
  and hicolor icons
- NixOS module (programs.openscreen.enable) with xdg-desktop-portal
- Home Manager module for per-user installation
- Overlay for composing with other flakes

Tested: nix flake show, nix develop, nix build, nixos-rebuild switch

.envrc

@@ -0,0 +1 @@
+use flake

.gitignore

@@ -34,3 +34,8 @@ playwright-report/
 
 # Vitest browser mode screenshots
 __screenshots__/
+
+# Nix
+result
+result-*
+.direnv/

flake.lock

@@ -0,0 +1,27 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1775710090,
+        "narHash": "sha256-ar3rofg+awPB8QXDaFJhJ2jJhu+KqN/PRCXeyuXR76E=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "4c1018dae018162ec878d42fec712642d214fdfa",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,122 @@
+{
+  description = "OpenScreen — desktop screen recorder with built-in editor";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+  };
+
+  outputs =
+    { self, nixpkgs }:
+    let
+      systems = [
+        "x86_64-linux"
+        "aarch64-linux"
+      ];
+      forAllSystems = f: nixpkgs.lib.genAttrs systems (system: f nixpkgs.legacyPackages.${system});
+    in
+    {
+      # -- Per-system outputs (packages, dev shells) --
+
+      packages = forAllSystems (pkgs: {
+        openscreen = pkgs.callPackage ./nix/package.nix { };
+        default = self.packages.${pkgs.stdenv.hostPlatform.system}.openscreen;
+      });
+
+      devShells = forAllSystems (
+        pkgs:
+        let
+          electron = pkgs.electron;
+
+          # Libraries Electron needs at runtime on Linux
+          runtimeLibs = with pkgs; [
+            # X11
+            libx11
+            libxcomposite
+            libxdamage
+            libxext
+            libxfixes
+            libxrandr
+            libxtst
+            libxcb
+            libxshmfence
+
+            # Wayland
+            wayland
+
+            # GTK / UI toolkit
+            gtk3
+            glib
+            pango
+            cairo
+            gdk-pixbuf
+            atk
+            at-spi2-atk
+            at-spi2-core
+
+            # Graphics
+            mesa
+            libGL
+            libdrm
+            vulkan-loader
+
+            # Networking / crypto (NSS for Chromium)
+            nss
+            nspr
+
+            # Audio
+            alsa-lib
+            pipewire
+            pulseaudio
+
+            # System
+            dbus
+            cups
+            expat
+            libnotify
+            libsecret
+            util-linux # libuuid
+          ];
+        in
+        {
+          default = pkgs.mkShell {
+            packages = with pkgs; [
+              nodejs_22
+              electron
+
+              # Native module compilation
+              python3
+              pkg-config
+              gcc
+
+              # Playwright browser tests
+              playwright-driver.browsers
+            ];
+
+            # Electron's prebuilt binary needs these at runtime
+            LD_LIBRARY_PATH = pkgs.lib.makeLibraryPath runtimeLibs;
+
+            # Tell the npm `electron` package to use the Nix-provided binary
+            # instead of downloading its own. vite-plugin-electron respects this.
+            ELECTRON_OVERRIDE_DIST_PATH = "${electron}/lib/electron";
+
+            # Playwright browser path for test:browser / test:e2e
+            PLAYWRIGHT_BROWSERS_PATH = "${pkgs.playwright-driver.browsers}";
+            PLAYWRIGHT_SKIP_BROWSER_DOWNLOAD = "1";
+
+            shellHook = ''
+              echo "OpenScreen dev shell — node $(node --version), electron v$(electron --version 2>/dev/null | tr -d 'v')"
+            '';
+          };
+        }
+      );
+
+      # -- System-wide outputs (modules, overlay) --
+
+      overlays.default = final: _prev: {
+        openscreen = self.packages.${final.stdenv.hostPlatform.system}.openscreen;
+      };
+
+      nixosModules.default = import ./nix/module.nix self;
+      homeManagerModules.default = import ./nix/hm-module.nix self;
+    };
+}

nix/hm-module.nix

@@ -0,0 +1,36 @@
+# Home Manager module for OpenScreen
+# Usage in flake-based Home Manager config:
+#
+#   inputs.openscreen.url = "github:siddharthvaddem/openscreen";
+#
+#   { inputs, ... }: {
+#     imports = [ inputs.openscreen.homeManagerModules.default ];
+#     programs.openscreen.enable = true;
+#   }
+self:
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+
+let
+  cfg = config.programs.openscreen;
+in
+{
+  options.programs.openscreen = {
+    enable = lib.mkEnableOption "OpenScreen screen recorder";
+
+    package = lib.mkOption {
+      type = lib.types.package;
+      default = self.packages.${pkgs.stdenv.hostPlatform.system}.openscreen;
+      defaultText = lib.literalExpression "inputs.openscreen.packages.\${pkgs.stdenv.hostPlatform.system}.openscreen";
+      description = "The OpenScreen package to use.";
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    home.packages = [ cfg.package ];
+  };
+}

nix/module.nix

@@ -0,0 +1,42 @@
+# NixOS module for OpenScreen
+# Usage in flake-based NixOS config:
+#
+#   inputs.openscreen.url = "github:siddharthvaddem/openscreen";
+#
+#   { inputs, ... }: {
+#     imports = [ inputs.openscreen.nixosModules.default ];
+#     programs.openscreen.enable = true;
+#   }
+self:
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+
+let
+  cfg = config.programs.openscreen;
+in
+{
+  options.programs.openscreen = {
+    enable = lib.mkEnableOption "OpenScreen screen recorder";
+
+    package = lib.mkOption {
+      type = lib.types.package;
+      default = self.packages.${pkgs.stdenv.hostPlatform.system}.openscreen;
+      defaultText = lib.literalExpression "inputs.openscreen.packages.\${pkgs.stdenv.hostPlatform.system}.openscreen";
+      description = "The OpenScreen package to use.";
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    environment.systemPackages = [ cfg.package ];
+
+    # Screen capture on Wayland requires xdg-desktop-portal.
+    # We enable the base portal; users should also enable a
+    # desktop-specific portal (e.g. xdg-desktop-portal-gtk,
+    # xdg-desktop-portal-hyprland) in their DE config.
+    xdg.portal.enable = lib.mkDefault true;
+  };
+}

nix/package.nix

@@ -0,0 +1,130 @@
+{
+  lib,
+  buildNpmPackage,
+  nodejs_22,
+  electron,
+  makeWrapper,
+  makeDesktopItem,
+  copyDesktopItems,
+}:
+
+buildNpmPackage {
+  nodejs = nodejs_22;
+  pname = "openscreen";
+  version = "1.3.0";
+
+  src =
+    let
+      fs = lib.fileset;
+      maybe = fs.maybeMissing;
+    in
+    fs.toSource {
+      root = ../.;
+      fileset = fs.difference ../. (
+        fs.unions [
+          ../nix
+          ../flake.nix
+          ../flake.lock
+          (maybe ../release)
+          (maybe ../test-results)
+          (maybe ../playwright-report)
+          (maybe ../.github)
+          (maybe ../.vscode)
+          (maybe ../.idea)
+          (maybe ../.kiro)
+          (maybe ../.envrc)
+          (maybe ../.direnv)
+          (fs.fileFilter (file: file.hasExt "md") ../.)
+        ]
+      );
+    };
+
+  npmDepsHash = "sha256-Pd6J9TuggA9vM4s/LjdoK4MoBEivSzAWc/G2+pFOM2U=";
+
+  env.ELECTRON_SKIP_BINARY_DOWNLOAD = "1";
+
+  # electron-builder is not needed — we wrap system electron directly
+  npmFlags = [ "--ignore-scripts" ];
+  makeCacheWritable = true;
+
+  # vite-plugin-electron compiles electron/ sources into dist-electron/
+  # tsconfig has noEmit — tsc is type-check only
+  buildPhase = ''
+    runHook preBuild
+    npx vite build
+    runHook postBuild
+  '';
+
+  installPhase = ''
+    runHook preInstall
+
+    mkdir -p "$out/lib/openscreen"
+
+    # Renderer build output (index.html, JS chunks, copied public/ assets)
+    cp -r dist "$out/lib/openscreen/"
+
+    # Main process + preload (compiled by vite-plugin-electron)
+    cp -r dist-electron "$out/lib/openscreen/"
+
+    # Package manifest (electron reads "main" field to find entry point)
+    cp package.json "$out/lib/openscreen/"
+
+    # Strip devDependencies (electron, vitest, biome, playwright, etc.)
+    npm prune --omit=dev --no-save
+    cp -r node_modules "$out/lib/openscreen/"
+
+    # Asset resolution: when app.isPackaged is false, the main process resolves
+    # assets at <appPath>/public/assets/. Mirror the electron-builder
+    # extraResources layout so wallpapers load correctly.
+    mkdir -p "$out/lib/openscreen/public/assets"
+    cp -r public/wallpapers "$out/lib/openscreen/public/assets/wallpapers"
+
+    # Wrap system electron with the app directory
+    mkdir -p "$out/bin"
+    makeWrapper "${electron}/bin/electron" "$out/bin/openscreen" \
+      --add-flags "$out/lib/openscreen" \
+      --set ELECTRON_IS_DEV 0
+
+    # Install icons to hicolor theme
+    for size in 16 24 32 48 64 128 256 512 1024; do
+      icon="icons/icons/png/''${size}x''${size}.png"
+      if [ -f "$icon" ]; then
+        install -Dm644 "$icon" \
+          "$out/share/icons/hicolor/''${size}x''${size}/apps/openscreen.png"
+      fi
+    done
+
+    runHook postInstall
+  '';
+
+  nativeBuildInputs = [
+    makeWrapper
+    copyDesktopItems
+  ];
+
+  desktopItems = [
+    (makeDesktopItem {
+      name = "openscreen";
+      desktopName = "OpenScreen";
+      genericName = "Screen Recorder";
+      exec = "openscreen %U";
+      icon = "openscreen";
+      comment = "Desktop screen recorder with built-in editor";
+      categories = [
+        "AudioVideo"
+        "Video"
+        "Recorder"
+      ];
+      startupWMClass = "Openscreen";
+      terminal = false;
+    })
+  ];
+
+  meta = {
+    description = "Desktop screen recorder with built-in editor";
+    homepage = "https://github.com/siddharthvaddem/openscreen";
+    license = lib.licenses.mit;
+    mainProgram = "openscreen";
+    platforms = lib.platforms.linux;
+  };
+}