I'm Building a Browser for Reverse Engineers
Mon Oct 06 2025 authored by veritas
Preamble
In the expanding world of AI my heart still lies in AST transforms, browser fingerprinting, and anti-bot circumvention. In fact, that's the majority of this blog's content. But my workflow always felt... primitive. I was still manually sifting through page scripts, pasting suspicious snippets into an editor, and writing bespoke deobfuscators by hand. Tools like Webcrack and deobfuscate.io help, but the end-to-end loop still felt slow and manual. I wanted to build a tool that would be my web reverse-engineering Swiss Army knife
If you're just curious about what it looks like and don't care about how it works then here's a quick showcase:
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Humble Beginnings
My first idea was simple: make a browser extension. For an MVP I wanted to hook an arbitrary function like Array.prototype.push as early as possible and log every call to it.
Hooking functions in JavaScript
In JavaScript, it's trivial to hook into and override existing functions because you can reassign references at runtime. A common pattern is to stash the original function, replace it with a wrapper that does whatever instrumentation you want, and then call the original so the page keeps behaving normally:
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