The future is here; let's evenly distribute it!
The nixpkgs-update mission is to make nixpkgs the most up-to-date repository of software in the world by the most ridiculous margin possible. Here's how we are doing so far.
It provides an interactive tool for automating single package updates. Given a package name, old version, and new version, it updates the version, and fetcher hashes, makes a commit, and optionally a pull request. Along the way, it does checks to make sure the update has a baseline quality.
It is the code used by the GitHub bot @r-ryantm to automatically update nixpkgs. It uses package repository information from Repology.org, the GitHub releases API, and PyPI to generate a lists of outdated packages.