**ondone** is a tiny (~1 KB) Node.js utility that coordinates the completion of a set of asynchronous functions. It returns wrapper callbacks that can be used with any async runner (e.g., async.js, miniq); when all tasks finish it invokes a final “done” handler, propagates the first error it encounters, cancels the remaining tasks, and guards against multiple calls to the done handler. It’s aimed at library authors and developers who need a lightweight, framework‑agnostic way to batch and monitor async tasks without pulling in a full‑featured async library.