Keploy

Keploy is an open-source AI-powered API testing agent that automatically generates test cases and dependency mocks from real user traffic using eBPF, achieving up to 90% test coverage in minutes with zero code changes — and it's completely free for the open-source version. It's built for backend developers, QA engineers, and DevOps teams who want to eliminate the manual toil of writing unit and integration tests while ensuring production-like reliability in CI pipelines.

Based on our analysis of 870+ AI tools in the directory, Keploy stands out in the developer testing category by using record-and-replay methodology powered by eBPF kernel-level instrumentation. Instead of writing tests by hand, developers simply run their application through Keploy, which captures real API calls along with their database queries, Redis calls, and third-party service interactions. These captured traffic samples are then converted into deterministic test cases with auto-generated mocks, creating an isolated sandbox environment that can be replayed in CI for regression testing. The project has earned 15,600+ GitHub stars, surpassed 1.2M+ downloads, and generated over 200M+ mocks across its user base — a strong indicator of real-world adoption.

Compared to traditional testing frameworks like Jest, Pytest, or Postman, Keploy removes the need to write test code manually and handles mocking automatically. While tools like Postman focus on API collection testing and Jest requires developers to author assertions, Keploy's AI-powered approach auto-generates both tests and mocks from production-like traffic. It also provides coverage reporting and performance testing in the same workflow. The tool supports Go, Python, Java, Node.js, and other major backend languages, and includes a cloud offering for teams that need centralized test management, collaboration, and enterprise-grade deployment on top of the open-source core.