Coding style

Firefox code is using different programming languages. For each language, we are enforcing a specific coding style.

Getting Help

If you need help or have questions, please don’t hesitate to contact us via Matrix in the “Lint and Formatting” room (#lint:mozilla.org).

Coding Style User Guide

• C++ Coding style
  • Formatting code
  • Static analysis
  • Additional rules
  • C/C++ practices
  • Header files
  • Include directives
  • COM and pointers
  • IDL
  • Error handling
  • Strings
  • Usage of PR_(MAX|MIN|ABS|ROUNDUP) macro calls
  • Use of SpiderMonkey rooting typedefs
• Mode line
• Java Coding style
• JavaScript Coding style
  • Coding style
  • Methods and functions
  • JavaScript objects
  • Operators
  • Literals
  • Prefixes
  • Other advice
• Python Coding style
  • Coding style
  • Linting
  • Indentation
  • Other advice
• CSS Guidelines
  • Basics
  • Formatting
  • Overriding CSS
  • Using CSS variables
  • Localization
  • Writing cross-platform CSS
  • Theme support
  • Layout & performance
  • Misc
• Formatting C++ Code With clang-format
  • Manual formatting
  • Editor integration
  • Ignore lists
• RTL Guidelines
  • Mirroring layout
  • Mirroring elements
  • LTR text inside RTL contexts
  • Testing
  • See also
  • Credits
• SVG Guidelines
  • Pros and cons of SVG for images
  • Authoring guidelines
• Using C++ in Mozilla code
  • C++ language features
  • C++ and Mozilla standard libraries
  • Further C++ rules
  • Stuff that is good to do for C or C++