FYI I was able to vibe code "enough JavaScript to run the css part of WPT" in about a week. Might not work so well if you don't have a DOM or incremental rendering though, but could be worth looking into.
thanks, i was already looking at this. Most of my skipped tests are reftests with script tag inside, and big part of that script just builds the dom. Thats doable without a real js runtime.