First was just a test to see if I could. Then became a pretty fun test on iteration loops. How little I could be involved and what kind of instruction works best.
It's a language server for WAT, the webassembly text format. There are not many of these that exist in general, so it's very easy for this to claim the #1 spot.
It's a problem that has some clear correctness criteria so putting it in a loop with Claude Code on Opus 4.5 kept producing really nice results.
The repo includes a playground so you can see how it feels without needing to download anything. Check it out at https://wat-lsp.emnudge.dev/