Uptime Kuma is an easy-to-use self-hosted monitoring tool.

Requestly is an open-source tool that simplifies API development, testing, mocking, and integration for developers and QAs.

REST API client library for .NET

LangSmith Observability gives you complete visibility into agent behavior with tracing, real-time monitoring, alerting, and high-level insights into usage.

Mockoon is the easiest and quickest way to design and run mock REST APIs.

Playwright enables reliable end-to-end testing for modern web apps.