RxJS is a library for reactive programming using Observables, to make it easier to compose asynchronous or callback-based code.
This project is a rewrite of Reactive-Extensions/RxJS with better performance, better modularity, better debuggable call stacks, while staying mostly backwards compatible, with some breaking changes that reduce the API surface.
ReactiveX combines the Observer pattern with the Iterator pattern and functional programming with collections to fill the need for an ideal way of managing sequences of events.
By implementing immutable principles from functional programming and combining it with a declarative, stream-based syntx, RxJS makes code easier to test, maintain and troubleshoot.
Open source is a philosophy that promotes the free access and distribution of an end product, usually software or a program.