A Claude skill that teaches you new codebases from what you already know
https://github.com/mark-quinn/rosetta
Been meaning to build this for a while. Every time I dropped into an unfamiliar stack I'd spend the first week just mapping concepts I already knew along the lines of: "ok so this is basically just middleware, but they call it X here." and "is this the same as X in Typescript".
So I built two Claude Code skills that do that mapping for you.
/rosetta takes your existing stack as a starting point and explains the unfamiliar pattern in terms you already know.
/cartographer is for when you know the language fine but you're new to this specific codebase. Why is auth done this way? What's the gotcha nobody wrote down? It maps the decisions, not the syntax.
Both build a shared knowledge map per repo so you're not re-explaining the same ground every session. Comes with a familiarity score so you can see what you've covered and what you haven't.
Would love feedback — especially if there are language pairs or codebase patterns you think are missing.