typescript-best-practices
TypeScript Best Practices
Pair with React Best Practices
When working with React components (.tsx, .jsx files or @react imports), always load react-best-practices alongside this skill. This skill covers TypeScript fundamentals; React-specific patterns (effects, hooks, refs, component design) are in the dedicated React skill.
Type-First Development
Types define the contract before implementation. Follow this workflow:
- Define the data model - types, interfaces, and schemas first
- Define function signatures - input/output types before logic
- Implement to satisfy types - let the compiler guide completeness
- Validate at boundaries - runtime checks where data enters the system
Make Illegal States Unrepresentable
Use the type system to prevent invalid states at compile time.
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