Playwright E2E Testing for Next.js: Auth Setup, Stripe Checkout, and CI Integration

Unit tests catch logic bugs. E2E tests catch the bugs that actually kill your conversion rate -- the broken checkout flow, the login redirect loop, the payment form that silently fails. Here's a practical Playwright setup for Next.js focused on critical paths. Setup npm install -D @playwright/test npx playwright install chromium // playwright.config.ts import { defineConfig } from '@playwright/test' export default defineConfig({ testDir: './e2e', fullyParallel: true, retries: process.env.CI ? 2 : 0, reporter: 'html', use: { baseURL: 'http://localhost:3000', trace: 'on-first-retry', screenshot: 'only-on-failure' }, webServer: { command: 'npm run dev', url: 'http://localhost:3000', reuseExistingServer: !process.env.CI }, projects: [ { name: 'setup', testMatch: /global.setup\.ts/ }, { name: 'chromium', use: { storageState: 'e2e/.auth/user.json' }, dependencies: ['setup'] } ] }) Auth Setup (Sign In Once, Use Everywhere) // e2e/global.setup.ts import { test as setup } from '@playwright/test