Tools

• Cyberhef - The Cyber Swiss Army Knife
• Postwoman - API request builder
• Online htaccess redirect tester
• CSR Decoder and Certificate Decoder
• SSL Server Test
• DNS CAA record generator

Documents / List of Documents

• All cheat sheets in one page (EN)
• Free for Dev (EN)
• rsapkf/goodies (EN)
• Unix Toolbox (EN)
• Raccourcis clavier bash (FR)

Web

• History of the browser user-agent string (EN)
• L’histoire des User-Agents (FR)

Web Server - Nginx

• trimstray/nginx-admins-handbook (EN)

VCS - GIT

• Git basics - the only introduction you'll ever need! (EN)
• Git Internal (EN)