Playwright

Playwright Test is an end-to-end test framework for modern web apps. It bundles test runner, assertions, isolation, parallelization and rich tooling.

Installing browsers for Playwright under NixOS

At first run, Playwright will prompt the user to run playwright install to install browsers. However, the browsers will not function due to missing dependencies.

The nixpkgs package playwright-driver.browsers provides a packaged form of the browsers that can be assigned to the PLAYWRIGHT_BROWSERS_PATH environment variable.

An example shell.nix that installs Visual Studio Code and Playwright.

{ pkgs ? import <nixpkgs> {} }:
  pkgs.mkShell {
    nativeBuildInputs = with pkgs; [
      vscode # if you want vscode
      nodejs_latest
      playwright-driver.browsers
    ];

    shellHook = ''
      export PLAYWRIGHT_BROWSERS_PATH=${pkgs.playwright-driver.browsers}
      export PLAYWRIGHT_SKIP_VALIDATE_HOST_REQUIREMENTS=true
      export PLAYWRIGHT_HOST_PLATFORM_OVERRIDE="ubuntu-24.04" # Seems like it is not needed?

      # These lines are needed if the npm-installed version of playwright (in package[-lock].json)
      # does not match the nix version of playwright contained in pkgs.
      # (by default each playwright version hardcoded a specific version of the browser for extra compatibility)
      export PLAYWRIGHT_NODEJS_PATH=${pkgs.nodejs_latest}/bin/node
      playwright_chromium_revision="$(${pkgs.jq}/bin/jq --raw-output '.browsers[] | select(.name == "chromium").revision' ${pkgs.playwright-driver}/browsers.json)"
      export PLAYWRIGHT_LAUNCH_OPTIONS_EXECUTABLE_PATH=${pkgs.playwright-driver.browsers}/chromium-$playwright_chromium_revision/chrome-linux/chrome
    '';
}

Note: The version of Playwright in Nixpkgs and your node developer environment (in package[-lock].json) must match unless you define PLAYWRIGHT_LAUNCH_OPTIONS_EXECUTABLE_PATH as shown above to force playwright to use a different browser than the hardcoded version. See also this discussion.

Using flake

This can easily be adapted within a flake like:

{
  description = "A very basic flake";

  inputs = {
    flake-parts.url = "github:hercules-ci/flake-parts";
    nixpkgs.url = "github:nixos/nixpkgs";
  };
  
  outputs = { flake-parts, ... } @ inputs: flake-parts.lib.mkFlake { inherit inputs; } {
    perSystem = { config, self', inputs', pkgs, system, ... }: {
      devShells.default = pkgs.mkShell {
        nativeBuildInputs = with pkgs; [
          nodejs_latest
          playwright-driver.browsers
        ];

        shellHook = ''
          export PLAYWRIGHT_BROWSERS_PATH=${pkgs.playwright-driver.browsers}
          export PLAYWRIGHT_SKIP_VALIDATE_HOST_REQUIREMENTS=true;
          export PLAYWRIGHT_NODEJS_PATH=${pkgs.nodejs_latest}/bin/node
          playwright_chromium_revision="$(${pkgs.jq}/bin/jq --raw-output '.browsers[] | select(.name == "chromium").revision' ${pkgs.playwright-driver}/browsers.json)"
          export PLAYWRIGHT_LAUNCH_OPTIONS_EXECUTABLE_PATH=${pkgs.playwright-driver.browsers}/chromium-$playwright_chromium_revision/chrome-linux/chrome
          echo "Using $PLAYWRIGHT_LAUNCH_OPTIONS_EXECUTABLE_PATH"
        '';
      };
    };
    # Declared systems that your flake supports. These will be enumerated in perSystem
    systems = [ "x86_64-linux" "aarch64-linux" "x86_64-darwin" "aarch64-darwin" ];
  };
}

Using Devenv

With Devenv you can also set certain environment variables and pin packages to make playwright work. Again, make sure to pin to the same version of playwright in devenv.yaml and package.json!

devenv.nix

{ pkgs, lib, config, inputs, ... }:

let
  pkgs-playwright = import inputs.nixpkgs-playwright { system = pkgs.stdenv.system; };
  browsers = (builtins.fromJSON (builtins.readFile "${pkgs-playwright.playwright-driver}/browsers.json")).browsers;
  chromium-rev = (builtins.head (builtins.filter (x: x.name == "chromium") browsers)).revision;
in
{
  # https://devenv.sh/basics/
  env = {
    PLAYWRIGHT_BROWSERS_PATH = "${pkgs-playwright.playwright.browsers}";
    PLAYWRIGHT_SKIP_VALIDATE_HOST_REQUIREMENTS = true;
    PLAYWRIGHT_NODEJS_PATH = "${pkgs.nodejs}/bin/node";
    PLAYWRIGHT_LAUNCH_OPTIONS_EXECUTABLE_PATH = "${pkgs-playwright.playwright.browsers}/chromium-${chromium-rev}/chrome-linux/chrome";
  };

  # https://devenv.sh/packages/
  packages = with pkgs; [
    just
    nodejs
  ];

  # https://devenv.sh/languages/
  languages.javascript.enable = true;

  dotenv.disableHint = true;
  cachix.enable = false;

  # https://devenv.sh/scripts/
  scripts.intro.exec = ''
    playwrightNpmVersion="$(npm show @playwright/test version)"
    echo "❄️ Playwright nix version: ${pkgs-playwright.playwright.version}"
    echo "📦 Playwright npm version: $playwrightNpmVersion"

    if [ "${pkgs-playwright.playwright.version}" != "$playwrightNpmVersion" ]; then
        echo "❌ Playwright versions in nix (in devenv.yaml) and npm (in package.json) are not the same! Please adapt the configuration."
    else
        echo "✅ Playwright versions in nix and npm are the same"
    fi

    echo
    env | grep ^PLAYWRIGHT
  '';

  enterShell = ''
    intro
  '';

  # See full reference at https://devenv.sh/reference/options/
}

devenv.yaml

# yaml-language-server: $schema=https://devenv.sh/devenv.schema.json
inputs:
  nixpkgs:
    url: github:NixOS/nixpkgs/nixos-unstable
  # Currently pinned to: playwright@1.52.0
  # See https://search.nixos.org/packages?channel=unstable&from=0&size=50&sort=relevance&type=packages&query=playwright
  nixpkgs-playwright:
      url: github:NixOS/nixpkgs/979daf34c8cacebcd917d540070b52a3c2b9b16e

package.json

{
  "name": "e2e-tests-ng",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "devDependencies": {
    "@playwright/test": "1.52.0",
    "eslint": "^8.41.0"
  },
  "engines": {
    "node": ">=18.0.0"
  },
  "scripts": {
    "playwright:test": "playwright test",
    "playwright:test:ui": "playwright test --ui",
    "playwright:install": "playwright install",
    "lint": "eslint ."
  },
  "dependencies": {
    "dotenv": "^16.0.3",
    "jsrsasign": "^11.0.0"
  }
}

Bun + Playwright

Here is a flake.nix that is working with bun instead of nodejs (working today 2026-01-23). Put flake.nix, playwright.config.ts, package.json and tests/example.spec.ts in the root directory of your project and run

• nix develop to install packages and enter the devShell
• bun install to download playwright dependencies to node_modules
• bun --bun playwright test --headed to test the setup
• bun playwright test --headed to verify that without --bun flag the nodejs version is run and bun library is not available.

flake.nix

{
  description = "Bun + Playwright dev shell";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs";
    flake-utils.url = "github:numtide/flake-utils";
  };

  outputs =
    {
      self,
      nixpkgs,
      flake-utils,
      ...
    }:
    flake-utils.lib.eachDefaultSystem (
      system:
      let
        pkgs = import nixpkgs { inherit system; };
        browsers =
          (builtins.fromJSON (builtins.readFile "${pkgs.playwright-driver}/browsers.json")).browsers;
        chromium-rev = (builtins.head (builtins.filter (x: x.name == "chromium") browsers)).revision;
      in
      {
        devShells.default = pkgs.mkShell {
          packages = with pkgs; [
            bun
            playwright-driver.browsers
          ];

          shellHook = ''
            export PLAYWRIGHT_LAUNCH_OPTIONS_EXECUTABLE_PATH="${pkgs.playwright-driver.browsers}/chromium-${chromium-rev}/chrome-linux64/chrome";
          '';
        };
      }
    );
}

playwright.config.ts

import { defineConfig, devices } from '@playwright/test';

export default defineConfig({
  projects: [
    {
      name: 'chromium',
      use: {
        ...devices['Desktop Chrome'],
        launchOptions: {
          executablePath: process.env.PLAYWRIGHT_LAUNCH_OPTIONS_EXECUTABLE_PATH,
        },
      },
    },
  ],
});

package.json

{
  "$schema": "https://json.schemastore.org/package.json",
  "name": "playwright_with_bun",
  "version": "1.0.0",
  "description": "Playwright tests with Bun",
  "scripts": {
    "test": "bun --bun playwright test"
  },
  "dependencies": {
    "@playwright/test": "^1.58.0",
    "playwright-core": "^1.58.0"
  },
  "devDependencies": {
    "@types/bun": "^1.3.6"
  }
}

tests/example.spec.ts

import { test, expect } from '@playwright/test';

test('basic test', async ({ page }) => {
  await page.goto('https://example.com');
  await expect(page).toHaveTitle(/Example/);
});

test('Bun.stripANSI available', async () => {
  expect(typeof Bun.stripANSI).toBe('function');
});

test output

[michi@nixos:~/dev/playwright_with_bun]$ bun --bun playwright test --headed

Running 2 tests using 1 worker

  ✓  1 [chromium] › tests/example.spec.ts:3:0 › basic test (1.1s)
  ✓  2 [chromium] › tests/example.spec.ts:8:0 › Bun.stripANSI available (3ms)

  2 passed (2.9s)

[michi@nixos:~/dev/playwright_with_bun]$ bun playwright test --headed
ReferenceError: Bun is not defined
    at Object.<anonymous> (/home/michi/dev/playwright_with_bun/playwright.config.ts:10:27)
    at Module._compile (node:internal/modules/cjs/loader:1706:14)
    at Module.newCompile2 (/home/michi/dev/playwright_with_bun/node_modules/playwright/lib/third_party/pirates.js:46:29)
    at Object.<anonymous> (node:internal/modules/cjs/loader:1839:10)
    at Object.newLoader2 [as .ts] (/home/michi/dev/playwright_with_bun/node_modules/playwright/lib/third_party/pirates.js:52:22)
    at Module.load (node:internal/modules/cjs/loader:1441:32)
    at Function._load (node:internal/modules/cjs/loader:1263:12)
    at TracingChannel.traceSync (node:diagnostics_channel:328:14)
    at wrapModuleLoad (node:internal/modules/cjs/loader:237:24)
    at Module.require (node:internal/modules/cjs/loader:1463:12)
    at require (node:internal/modules/helpers:147:16)
    at requireOrImport (/home/michi/dev/playwright_with_bun/node_modules/playwright/lib/transform/transform.js:225:18)
    at loadUserConfig (/home/michi/dev/playwright_with_bun/node_modules/playwright/lib/common/configLoader.js:107:89)
    at loadConfig (/home/michi/dev/playwright_with_bun/node_modules/playwright/lib/common/configLoader.js:119:28)
    at loadConfigFromFile (/home/michi/dev/playwright_with_bun/node_modules/playwright/lib/common/configLoader.js:331:10)
    at runTests (/home/michi/dev/playwright_with_bun/node_modules/playwright/lib/program.js:197:18)
    at i.<anonymous> (/home/michi/dev/playwright_with_bun/node_modules/playwright/lib/program.js:70:7)
error: "playwright" exited with code 1

Notes

• The Playwright Test for VSCode extension does not currently support Bun. The Node.js runtime may be used instead.
• Playwright version 1.58 is the first version where the command bun --bun playwright test works.
• see also https://github.com/MBanucu/bun-playwright-nix