Nixpkgs now allows (if I’m not mistaken) merges by package maintainers, who are usually not committers, by sending commands to a merge bot:
https://github.com/NixOS/nixpkgs-merge-bot
https://github.com/NixOS/rfcs/pull/172/files#diff-d44ac0cd941ca5ce5e56388cd1a97171b299feed94aae4a405b3cc56b26d8b0c
Food for thought, fellow #Guix.