Bluebird

Bluebird is a fully featured promise library with focus on innovative features and performance. Promises in Node.js 10 are significantly faster than before. Bluebird still includes a lot of features like cancellation, iteration methods and warnings that native promises don't. If you are using Bluebird for performance rather than for those - please consider giving native promises a shot and running the benchmarks yourself. When using script tags the global variables Promise and P (alias for Promise) become available. Bluebird runs on a wide variety of browsers including older versions. Synchronous inspection allows you to retrieve the fulfillment value of an already fulfilled promise or the rejection reason of an already rejected promise synchronously. The default approach of bluebird is to immediately log the stack trace when there is an unhandled rejection.