I'd like to help you rework this a bit

[benlesh]

I think this library has some great goals, and I'd like to see it take full advantage of RxJS v6's modularity and "tree-shakability"

I recommend:

1. Dropping support for RxJS 4
2. Dropping the use of the Rx global
3. Using RxJS 6 directly in this library (This will also enable supporting RxJS 5 if users want that)
4. Getting users to use "pipeable" operators.

All of this will drastically simplify your codebase as well as make apps built with vue-rx and Webpack 4 a lot smaller.