pexip/playwright

Purpose and distribution

Playwright is a Node.js/TypeScript browser-automation platform: a common API and test runner drive Chromium, Firefox, and WebKit, with CLI, MCP/agent, component-testing, trace, and reporting surfaces. Published package facades expose CommonJS/ESM/types and install hooks from packages/playwright/package.json, packages/playwright-core/package.json, and browser-specific packages such as packages/playwright-chromium/package.json.

Primary entry points

Library consumers import playwright or playwright-core; package entry shims resolve into the core client/server implementation. User-facing commands enter through packages/playwright/cli.js and packages/playwright-core/cli.js. Test commands are assembled in packages/playwright/src/program.ts and packages/playwright/src/cli/testActions.ts; core CLI installation/browser actions live in packages/playwright-core/src/cli/program.ts. MCP starts from packages/playwright-core/src/entry/mcp.ts and packages/playwright-core/src/tools/mcp/program.ts.

Client, protocol, and server boundary

The public client API models browsers, contexts, pages, locators, network, artifacts, and tracing in packages/playwright-core/src/client/playwright.ts, packages/playwright-core/src/client/page.ts, and packages/playwright-core/src/client/locator.ts. Calls cross a channel-based object protocol: generated/spec-defined contracts are rooted in packages/protocol/spec/playwright.yml, validated/serialized in packages/playwright-core/src/protocol/validator.ts, and bridged by server dispatchers such as packages/playwright-core/src/server/dispatchers/playwrightDispatcher.ts. This boundary permits in-process operation plus remote pipe/WebSocket transports.

Browser lifecycle and engine adapters

The server owns browser launch, context isolation, page/frame state, instrumentation, downloads, screenshots, video, and network routing. Core orchestration is in packages/playwright-core/src/server/playwright.ts, packages/playwright-core/src/server/browserType.ts, and packages/playwright-core/src/server/browserContext.ts. Engine-specific adapters translate the shared model to Chromium CDP, Firefox’s Juggler protocol, and WebKit protocol: packages/playwright-core/src/server/chromium/crBrowser.ts, packages/playwright-core/src/server/firefox/ffBrowser.ts, and packages/playwright-core/src/server/webkit/wkBrowser.ts. Browser acquisition/version registry is separate in packages/playwright-core/src/server/registry/index.ts.

Page-resident automation

A bundled injected script runs inside controlled pages to implement selector evaluation, locator generation, actionability support, accessibility snapshots, recorder behavior, and WebAuthn/mock capabilities. Key sources are packages/injected/src/injectedScript.ts, packages/injected/src/selectorEvaluator.ts, and packages/injected/src/ariaSnapshot.ts. This is a strict execution boundary: Node-side server code requests behavior, while DOM traversal and element resolution execute in the browser realm.

Test runner pipeline

@playwright/test layers configuration, project expansion, discovery/transformation, worker scheduling, fixtures, retries, assertions, and reporters over the library. Configuration/loading begins at packages/playwright/src/common/configLoader.ts; scheduling and child-process control are in packages/playwright/src/runner/testRunner.ts and packages/playwright/src/runner/workerHost.ts; test execution/fixtures run in packages/playwright/src/worker/workerMain.ts and packages/playwright/src/worker/fixtureRunner.ts. Results flow through reporter implementations, including blob and HTML formats, in packages/playwright/src/reporters/blob.ts and packages/playwright/src/reporters/html.ts.

Artifacts and interactive tooling

Tracing records server-side actions and snapshots, then emits trace artifacts consumed by shared trace models and browser UIs: packages/playwright-core/src/server/trace/recorder/tracing.ts, packages/isomorphic/trace/traceModel.ts, and packages/trace-viewer/src/ui/workbench.tsx. Recorder/codegen uses packages/playwright-core/src/server/recorder/recorderApp.ts with the React frontend in packages/recorder/src/recorder.tsx. Agent-facing MCP tools translate structured requests into browser sessions via packages/playwright-core/src/tools/mcp/browserFactory.ts and packages/playwright-core/src/tools/backend/tools.ts; the dashboard provides live session control through packages/dashboard/src/dashboard.tsx.

Runtimes, native dependencies, and infrastructure

The dominant runtime is Node.js with TypeScript/JavaScript; interactive viewers/dashboard are Vite/React applications. Browser execution depends on downloaded Chromium, Firefox, and WebKit binaries and OS-native dependencies; Firefox/WebKit include maintained upstream patches under browser_patches/firefox/juggler and browser_patches/webkit. Android support includes an ADB-facing server and Gradle-built driver at packages/playwright-core/src/server/android/android.ts and packages/playwright-core/src/server/android/driver. CI publishes npm, Docker, and extension artifacts through workflows including .github/workflows/publish_release.yml, .github/workflows/publish_release_docker.yml, and .github/workflows/publish_extension.yml.