Introduction

Start with the license, because that is the part that decides whether any of this is legal. MIT. Use, copy, modify, merge, publish, distribute, sublicense, sell. So yes, I forked VS Code, and I am up to date with main.

You are allowed to think this is ridiculous. Cursor forked VS Code and just took $60 billion from SpaceX. Windsurf did the same and got bought out from under Google. So the idea is not the crazy part.

Here is why I care. I worked on the VS Code team as an advocate for VS Code and Copilot. I gave feedback on what the Copilot experience should feel like. I think it has gone off the rails. I open the editor now and I see text and boxes and buttons, and I have ideas about what a good experience looks like instead. With Opus 5, Sonnet 5, Fable, and the skills I have built up, I can go build it.

But that is not the interesting part for you.

The interesting part is: src/vs/workbench/browser/actions/media is four or five levels deep and that is one branch of one directory. Millions of lines. I have never dug into this codebase. Neither have you.

So how do you navigate a repo this size without blowing up your context window?

That is the whole course. I go in face first and you come with me.