The Conventional Commits convention for commit messages — the format and what it buys you, checking messages with commitlint and lefthook at commit time, and checking them in CI
Oh My Posh, the prompt theme engine for every shell — installing it and a Nerd Font, picking a theme, writing your own config from scratch, and the trap it sets when you also use mise
Jujutsu (jj), the Git-compatible version control system — installing it, how it differs from Git, and the commands you type every day
Sapling (sl), Meta's Git-compatible VCS — installing it, stacks, one PR per commit with sl pr submit, ReviewStack, and the sl web GUI
Declaring packages, dotfiles, tools and a finishing task in one config file, and bringing a new machine up to it with a single mise bootstrap
Writing environment variables that only apply inside a directory into mise.toml, and the traps in loading .env