There are global guidelines which affect every single language, file or folder.



  • Validate your code through the W3C validators.
  • There is something called Accessibility.
  • Don’t forget about HiDPI, Retina and High Resolutions displays.
  • Proper fallbacks should be available if a connection is slow or features are disabled.
  • Progressive enhancement, graceful degradation and responsive design are buzzwords you care about.
  • Develop with modularity and extensibility in mind.
  • Documentation is your friend.



  • Use 4 spaces for indentation.

Not 2, 3 or 8 – no tabs – if you are able to do 3 3/4, that’s good enough

Line Length


  • Don’t breach 120 characters per line.

Not even for HTML. We even encourage you to use 80 characters per line. Yes, screens have got much bigger over the last few years, but your brain hasn’t. Better to use screen estate for splits, anyway.



  • lowercase, camelCase or hyphened separation are all good; use no special characters except for underscore _.
  • Use dashes - for file naming, unless expressly counterindicated (e.g. in HTML template names).
  • Always use full words instead of abbreviations: number is better than nr.
  • BEM is a nice methodology to be aware of.
“There are only two hard things in Computer Science:
cache invalidation and naming things” – Phil Karlton



  • We always use double "." quotes for everything, except in JavaScript, where we use single '.' quotes.