typescript-pedantry

To ensure type safety for external API inputs in TypeScript, use Zod schemas to validate data at system boundaries. This guarantees runtime data matches compile-time types, preventing errors from untrusted inputs.

The best way to handle variant types without unsafe type assertions is using discriminated unions. Defining a common literal property across object types allows TypeScript to safely narrow types during control flow checks.

To configure strict TypeScript compiler flags, set `strict: true` in your `tsconfig.json`. This enables comprehensive compile-time type checking rules, preventing common type-related bugs across your codebase.

TypeScript throws runtime errors despite passing type checks because compile-time types are erased at runtime. Integrating Zod validation at system boundaries ensures incoming data actually matches expected structures.

You need Zod when refactoring a JavaScript codebase to TypeScript if you require runtime data validation at system boundaries. While strict compile-time checks catch internal bugs, Zod ensures external inputs match defined schemas.

TypeScript patterns that improve code maintainability include using `as const` for immutable literals, template literal types for string unions, and barrel exports for organized module loading. These features ensure cleaner, robust codebases.