Spying on my Browser (in Zig)

nubskr builds a forward proxy from scratch in Zig to intercept, parse, and forward HTTP and HTTPS traffic from a browser.

I built a forward proxy in Zig and connected my browser to it. The goal was to put a real program between the browser and the internet: accept browser connections, parse HTTP requests, forward traffic to the real server, handle HTTPS tunneling with CONNECT, and send everything back through the proxy. In this video, we build the proxy step by step, from raw streams and HTTP forwarding to HTTPS tunneling, failure handling, CLI testing, and finally pointing the browser at our own proxy. It is a small piece of infrastructure, but once your browser is talking through code you wrote yourself, the web starts feeling a lot less magical. Built with Zig. Chapters 00:00 - Teaser 00:41 - Intro 01:10 - Forward Proxies 03:17 - Handling Streams 07:04 - HTTP vs HTTPS 10:55 - Forwarding HTTP Traffic 16:38 - Handling HTTPS Tunneling 26:15 - Failure Models 27:40 - Testing the CLI 28:34 - Connecting the Browser #zig #systemsprogramming #networking