APIGenix – Watch, Pause and Edit API Calls on Localhost

Overview APIGenix sits between your local website (for example, localhost:4200) and your real API. You see every call and its response, and you can stop any call, change it, and send it on. It is built for fast testing, without the weight of a large proxy tool. It is free and everything stays on your PC.

Key Features

• Live list of every API call with method, URL, status and time

• Pause a request or a response, edit it, then Forward (or Forward all)

• Pause rules by URL, for example only api/auth/login, so other calls pass freely

• Edit headers and body of requests and responses

• Saved history of all calls, with search across all saved calls

• Copy a call as cURL and other formats

• Export as HAR, CSV or HTML report

• Choose the listening port and the real API address

Technical Highlights

• Native C# reverse proxy built on the Windows HTTP listener

• Rules and history saved locally on your PC

• No certificates or system proxy changes needed for plain HTTP localhost

• Single small exe (about 120 KB)

My Role I designed and built this tool end to end, from the idea and UI to the Windows build and release packaging.

Outcome Saves developers time when testing login flows, error responses and slow APIs, with a simple and light tool.

Download Free offline download. Version 1.0.0, size about 120 KB, freeware (source not public). System requirements: Windows 10 or 11 (64-bit). Works fully offline.