Monorepos and Shared Test Utilities

In larger organisations, Playwright tests often live in monorepos with multiple apps and packages. Designing shared utilities carefully prevents duplication while keeping boundaries clear between projects.

Sharing Playwright Utilities in a Monorepo #

A common approach is to create a dedicated test utilities package that exports page models, service helpers, fixtures and configuration helpers. Individual apps then depend on this package.

monorepo/
  packages/
    test-utils/
      src/
        models/
        services/
        fixtures/
      package.json
  apps/
    shop-frontend/
      tests/
      playwright.config.ts
    admin-frontend/
      tests/
      playwright.config.ts

// apps/shop-frontend/playwright.config.ts
import { defineConfig } from '@playwright/test';
import { shopProjectDefaults } from '@org/test-utils/config';

export default defineConfig({
  ...shopProjectDefaults,
});

Good boundaries let teams share high-value utilities without turning the monorepo into a single tangled codebase.

Common Mistakes #

Mistake 1 — Copy-pasting utilities between apps #

This leads to divergence.

❌ Wrong: Duplicating page models or fixtures into each app folder.

✅ Correct: Move shared logic into a common package and version it.

Mistake 2 — Putting app-specific logic into shared packages #

This reduces reusability.

❌ Wrong: Hard-coding URLs or features for a single app inside the utilities package.

✅ Correct: Keep shared packages generic and pass app-specific details via configuration.