Writing
Everything I've written here.
How I manage four NixOS machines (one server, three workstations) from a single flake: profiles, modular composition, sops-nix secrets, hot-reload dotfiles, and a Justfile that hides the rough edges.
From a WP multisite with Elementor, PHP-FPM, and MariaDB - to pure static nginx in one afternoon. The plan, the gotchas, and the 500 MB of RAM I got back.
Seven weeks, 62 libretro cores, a custom web dashboard streaming the screen in HW-encoded MJPEG, and the BSP decisions I'd make again.