ReqRes

The application runs as a native macOS utility that intercepts HTTP and HTTPS traffic between a user’s programs and remote servers, presenting each request and response in plain‑text format without additional configuration. It functions as a man‑in‑the‑middle proxy, logging the full details of every exchange in real time, which allows developers to inspect headers, payloads, and status codes as they occur.

In addition to passive monitoring, the tool enables active mocking of endpoints or whole servers. Users can define rules that replace live responses with static content drawn from local files, facilitating rapid testing of edge cases and development work before a real API is available. The “Map Local” feature handles the matching and substitution automatically.

The software is open source and offered under a free tier, targeting developers who need an on‑machine solution for debugging, traffic analysis, and request mocking on macOS. Its design emphasizes minimal setup and direct integration with the operating system’s networking stack.