Seems to be missing uv.read_start.callback (and friends)?

Yes, I chose not to generate these. For simple types they are inlined.

--- @param stream uv.uv_stream_t
--- @param callback fun(err: string?, data: string?)
--- @return 0? success
--- @return string? err
--- @return string? err_name
function uv.read_start(stream, callback) end

Ok, but that means these files are not drop-in replacements for https://github.com/LuaCATS/luv, and switching to them requires annotation changes in Neovim (_system.lua, to be precise).

Yes. Providing a 100% drop-replacement for https://github.com/LuaCATS/luv was not my intended goal

That's fair, but could you then make the goal explicit in the PR description (which I suspect is garbled; the second paragraph doesn't make sense to me)?

I think the current PR description reflects the goal and makes no mention of https://github.com/LuaCATS/luv . However, I've added a note mentioning it is similar but different.

cc @truemedian @squeek502 . Sorry to ping, any chance of a review?