Worked across multiple nixpkgs repositories to deliver targeted build system improvements and package management updates using Nix. In GaloisInc/nixpkgs, updated development tooling by upgrading go-minimock and tmuxinator, which enhanced test generation reliability and streamlined local workflows. Addressed a Python build compatibility issue in raexera/nixpkgs by updating fsuae-launcher’s setup process, ensuring successful builds with modern tools. In srid/nixpkgs, removed the deprecated buf-language-server and guided users toward the buf package, while also upgrading the Gleam compiler for improved stability. The work emphasized deprecation cleanup, dependency upgrades, and cross-repository maintenance to reduce future support overhead.