writing-lib-functions

Organize library functions by separating them into multiple files within `src/lib`, enforcing a 50-line maximum per file. This modular structure makes functions easier to locate, understand, and reuse across your Next.js project.

Create reusable utility functions in `src/lib` by distributing related helpers across separate files, each capped at 50 lines. This approach prevents monolithic files and maintains clarity as your project grows.

Yes, this modular library structure applies to both frontend and backend code in Next.js. Organize core logic, calculations, helpers, and utilities in `src/lib` with consistent 50-line file limits across your entire application.

A 50-line limit per file improves readability and maintainability by preventing large, complex files. Smaller, focused files make functions easier to find, test, and reuse without overwhelming developers.

Break complex calculations into smaller, single-purpose functions distributed across multiple TypeScript files in `src/lib`, each staying under 50 lines. This enforces modularity while maintaining type safety and readability.

Use modular library functions when code is reused across multiple components or modules, or when logic is complex enough to benefit from dedicated files. Inline code works for one-off, trivial operations.