Async EventTarget is a experimental library exploring making event handling asynchronous.
It attaches an alsoAwait method to events being fired, which event handlers can use to submit promises.
Once all promises so submitted during event handling resolve, a promise for the dispatching event is fired.
Originally it was looking at Webpack's synchronous event-based build pipeline that got me thinking about this.
I wanted a more general way to build compiler or build pipelines, which are frequently a bunch of named events, and this came out as it's own piece of that puzzle.