This summary highlights the challenges of end-to-end testing and synthetic monitoring in JavaScript-heavy applications, where asynchronous code can make tests unstable. To address this issue, the article proposes using Playwright's fixture feature to automatically fail end-to-end tests if JavaScript throws exceptions, making it easier to catch problems without directly testing all features. The article also shows how to extend Playwright's test object with custom fixtures and overrides, including a configurable `failOnJSError` option. Additionally, it emphasizes the importance of re structuring projects to be ready for a scalable fixture setup, providing a base file that exports an extended Playwright setup, making it reusable and standardized across tests. The ultimate goal is to get the most out of end-to-end testing by actively monitoring broken functionality while testing critical user flows.