TypeScript + React Standards

Strict, reusable standards for TypeScript/React projects.

When to Use

Use this skill when:

• Writing or refactoring .ts / .tsx

• Moving inline types into types/

• Enforcing consistent type naming and result shapes

• Working in Next.js where special files allow extra exports

Non-Negotiables (MUST)

• One exported symbol per file for your own modules.

• No inline interface /type in components/hooks/utils/services/route handlers.

• Put shared shapes under types/<area>/... (one type per file).

• Avoid barrel files (index.ts ) that hide dependencies.

• After meaningful changes: run the project's standard checks (e.g. yarn check:all ).

Next.js Special-file Exceptions

• app//page.tsx , app//layout.tsx : allow default export

metadata/generateMetadata/viewport (etc.).

• app/api/**/route.ts : allow multiple HTTP method exports and route config exports.

Rules

TypeScript Standards

• ts-language-style

• Language & style (interface vs type, const vs let, English-only)

• ts-one-thing-per-file

• One thing per file (STRICT)

• ts-nextjs-exceptions

• Next.js special-file exceptions

• ts-types-strict

• Types (STRICT) - no inline types

• ts-helpers-strict

• Helpers (STRICT) - no helpers in components/hooks

• ts-nextjs-hygiene

• Next.js TS hygiene (docs-aligned)

• ts-validation

• Validation (run checks after changes)

Types Conventions

• types-one-type-per-file

• One type per file (STRICT)

• types-naming-patterns

• Naming patterns (Params, Result, Error, Props)

• types-result-shape

• Result shape for boundaries that can fail

• types-where-allowed

• Where types are allowed

Related Skills

• busirocket-core-conventions

• General file structure (one-thing-per-file, boundaries)

• busirocket-react-components-and-hooks

• Component and hook structure

• busirocket-refactor-workflow

• Refactoring workflow for TypeScript/React

How to Use

Read individual rule files for detailed explanations and code examples:

rules/ts-one-thing-per-file.md rules/ts-types-strict.md rules/types-one-type-per-file.md

Each rule file contains:

• Brief explanation of why it matters

• Code examples (correct and incorrect patterns)

• Additional context and best practices