luarocks.org
In short: LuaRocks (luarocks.org) accepts lua module listing. It is free to submit, takes only a few minutes, and scores 68/100 on our impact ranking (useful).
Create a useful Lua client or helper, publish its rockspec and include homepage, license and source links.
Only publish a working Lua module with correct dependencies and versioned source archives.
Priority is medium, which sets the band. It is free and quick to complete, which adjusts it within that band. The score ranks your queue — it is not a measure of domain authority.