How to Build a Custom Generic Utility Type in TypeScript

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Developer Vikash Kumar shares a reusable TypeScript utility type called Optional that allows specific properties of an existing type to be made optional without duplicating type definitions. The utility combines three built-in TypeScript helpers — Omit, Pick, and Partial — to selectively relax required fields. Kumar demonstrates its practical value in scenarios like API update functions, where some fields must remain required while others become flexible. The approach eliminates repetitive type declarations and improves code readability across larger projects. He argues that understanding core utility types as composable building blocks enables developers to craft cleaner, problem-specific type vocabularies.

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