FiddlerCore vs Whistle

FiddlerCore has no write-up on Specifiction yet; its figures are above.

Whistle is a free, MIT-licensed network debugging proxy for packet capture and traffic inspection. It supports HTTP, HTTPS, SOCKS, and reverse proxying, and can intercept and modify network traffic. Users define rules to change requests and responses; the Network interface filters captured requests in real time, while Composer supports replay and editing. WebSocket and TCP request and response data can be inspected, transmission paused or ignored, and custom data sent through Composer. HTTPS decryption requires enabling HTTPS capture and installing Whistle’s root certificate. The desktop version provides a graphical interface for macOS, Windows, and Linux. Its command-line version is intended for headless Linux servers, Docker containers, embedded systems, and IoT devices. Mobile capture instructions cover iOS and Android devices configured to use the proxy and trust its root certificate. Plugins extend Whistle’s functions and can be installed, configured, updated, and removed; the software can also be added to a project as an NPM module. The integrated Weinre tool supports debugging webpages on mobile devices from a computer on the same network. Internal requests can use username and password authentication, while proxy request permission control requires a plugin or custom plugin.