Hacker News on 30 March 2013

• Callbacks are imperative, promises are functional
• Worst CAPTCHA Ever
• What Major World Cities Look Like at Night, Minus the Light Pollution
• Effective Django
• Introduction to Guitar
• Lessons Learned from YouTube’s $300M Hole
• Standups are Not Poisonous
• M-Expressions in Haskell
• Zsh-lovers – tips, tricks and examples for the Z shell
• Saying Goodbye to a Sister