extra‑promise is a TypeScript library that adds a rich set of utilities for working with JavaScript `Promise`s and async functions. It provides helpers such as type‑guards, timeout/delay wrappers, async collection operators (map, filter, each, series, parallel, waterfall), promise‑based channels, deferred objects, concurrency primitives (semaphore, mutex, keyed mutex), and functions like `promisify`, `asyncify`, and `reusePendingPromises`, aimed at developers who need more control and ergonomics when handling asynchronous code.