TypeScript Newtypes

newtype-ts provides a robust and performant implementation of newtypes in TypeScript, allowing developers to define distinct types that share the same underlying runtime representation. This helps enforce type safety at compile time, preventing logical errors such as accidentally assigning a `USD` value to a `EUR` variable. The library is currently at version 0.3.5 and is actively maintained, with recent releases focusing on polish and bug fixes. Its key differentiators include a strong reliance on `fp-ts` and `monocle-ts` for functional programming patterns and optics, ensuring no runtime overhead, and offering built-in refinements for common data types like `Integer` or `NonEmptyString`. It supports TypeScript 3.5.1+ and is designed for performance, with newtype operations showing negligible overhead compared to raw type operations.