typescript-best-practices

To make illegal states unrepresentable in TypeScript, you should use discriminated unions and branded types. This approach structurally prevents invalid state combinations, ensuring type safety and reducing runtime errors throughout your project.

The best way to validate external data inputs in TypeScript is by integrating Zod for schema validation and data normalization. Zod enforces runtime validation at application boundaries, ensuring external data matches your defined types.

To ensure exhaustive handling in TypeScript switch statements, implement `never` checks within your logic. This technique enforces all code paths are considered, generating compile-time errors if any cases are missed.

Yes, you can refactor a JavaScript codebase using TypeScript best practices by enabling strict mode and applying type-first development. This process guides defining types, ensuring all possible states are handled, and validating external data inputs.

Yes, you need to enable strict mode for type-first development in TypeScript. Strict mode is required to enforce type safety, support const assertions, and fully leverage advanced features like discriminated unions.

You should not use Zod for runtime validation when handling internal, already type-safe data transfers within your TypeScript project. Zod is specifically designed for schema definition and data validation at application boundaries.