LazyPromise is a lightweight async primitive combining ideas from RxJS, native promises, and Effect. It offers a single-shot Observable, a lazy and cancelable promise with a familiar API, and supports generator syntax, type-safe errors, and dependency injection as a simpler alternative to Effect.
Effect TS is a TypeScript library that makes error handling explicit in the type system, automatically inferring all possible failure modes from composed functions and propagating them up the call stack. Unlike Promises, which hide failures, Effect forces developers to handle all error cases at compile time, preventing runtime surprises and improving program reliability.