Practical reference sheets — code-heavy, copy-paste-ready. Most are sourced from or inspired by learnxinyminutes.com ; annotations and CLI cookbooks are original.
Programming languages
Shell & scripting
Markup & styling
Query languages & filters
Text processing
Protocols
File Protocol dns.md DNS — records, resolution, dig/host tooling http.md HTTP — methods, status codes, headers, curl ssh.md SSH — keys, forwards, ProxyJump, sshd tcp.md TCP — handshake, states, ss/tcpdump tls.md TLS — handshake, certs, OpenSSL
Automation
Config files
Annotated reference configs in each tool’s native syntax — copy any block directly into your real config.
Tree
cheatsheets/
├── index.md
├── automation/ cron · github-actions · make · systemd
├── config/ .editorconfig · .gitconfig · docker-compose.yml · nginx.conf · ssh_config · tmux.conf
├── data/ csv · json · xml · yaml
├── markup/ html · latex · markdown
├── programming/ c · cs · go · java · kotlin · lua · python · rust · swift · typescript
├── protocols/ dns · http · ssh · tcp · tls
├── query/ graphql · jq · regex · sql
├── shell/ bash · powershell
├── styling/ css
├── text-processing/ awk · grep · sed
└── tools/
├── cli/ docker · git · nmap · yt-dlp
└── editors/ emacs · vim · vscode
11 items under this folder.