CODE_REVIEW_GUIDELINES.md

Code review guidelines

Backpack is Skyscanner's design system. It should be an encoding of the Skyscanner visual design language, patterns, and ideas.

Backpack should be the best way to build and design Skyscanner UI.

Anchoring in design

Backpack starts with design, and all changes or additions should be previously agreed on in the wider design community before being implemented in Backpack. In absence of having gone through design review, changes should have been reviewed and approved by a Backpack designer.

Quality

Backpack is intended to reduce work when implementing Skyscanner UI and should be of high quality. While it's expected that implementing UI as part of Backpack will take more time and effort than the equivalent work outside of Backpack, the results empower everyone to go faster.

All changes to Backpack should

• Follow the Backpack style guide.
• Pass all linting checks.
• Have zero warnings.
• Expose a delightful API surface.
• Have high test coverage.
• Match the design.
• Support RTL.
• Have considered accessibility and through the API encourage consumers to build accessible products. e.g. Making accessibilityLabel required rather than optional.
• Support theming when appropriate.
• Feature good examples.
• Follow Semantic Versioning (SemVer), erring on the side of too many breaking changes rather than shipping something breaking as a minor or patch.
• Have considered extreme cases such as users with larger text or smaller devices.
• Be well documented.
• Be closed for modification of look and feel.