Fourteen pages,
printable.
The references engineers reach for weekly. HTTP status codes, regex, git, kubectl, cron, SQL, shell, curl — plus Docker, redis-cli, psql, jq, tmux, and the DNS toolbox. Each fits on one A4 page. Print, pin, refer.
The fourteen sheets.
One page each, laid out for print. Open one and hit ⌘P.
HTTP status codes
1xx · 2xx · 3xx · 4xx · 5xx, with what each actually means.
Regex
Anchors, classes, quantifiers, lookarounds, flags.
Git
Move, undo, rewrite, recover. The 30 commands that matter.
kubectl
Inspect, apply, debug, port-forward.
Cron
Five fields. The non-obvious modifiers.
SQL
Joins, window functions, CTEs, set operations.
Shell
Parameter expansion, redirection, signals, glob patterns.
curl
The flags that matter for debugging.
Docker
Images, containers, volumes, compose, cleanup.
redis-cli
The core data types, TTLs, SCAN, pub/sub, memory debugging.
psql
Meta-commands, COPY, live queries, table sizes, EXPLAIN.
jq
Selectors, pipes, map/select, string interpolation, one-liners.
tmux
Sessions, windows, panes, copy mode, the config that matters.
DNS tools
dig, host, nslookup, whois — tracing a name to an address.
Pin them somewhere.
Each sheet has its own page, laid out as a single A4. Open one, then use your browser's print preview (⌘P / Ctrl+P) to save as PDF or print and pin near your terminal.