I have generally steered away from building open-source libraries mainly for selfish reasons (I didn't want to spend the time maintaining them) but I decided that the current work I was doing would benefit from input and improvement from others and so I decided to release two things as libraries and im really happy with how things went.
Both libraries are for MobX State Tree (MST) which I have been using for quite some time now. Its a fantastic library for managing your state in a clear and concise way tho there are some gotchas with parts of it. These libraries try to help with some of those gotchas and thus increase reliability when using MST.
MST Flow Pipe
This is a helper library for writing type-safe async code in MobX State Tree.
I wont go into all the details of how this one works, you can click the link above to read the readme. Briefly tho I felt that MST's async story was a little lacking when combined with Typescript so set out to improve it with this library.
I first talked about it on this issue which prompted me to release the lib.
My first version had some corner cases that didn't work quite right but thankfully @lorefnon picked up from where I left off and submitted a PR which greatly improved the library. Now it works fantastically, is infinitely expandable and handles errors in an elegant way.
Im really happy with the state of the library and I think the concepts could be borrowed and used in other libraries that use JS-generators instead of JS-promises such as redux-saga.
A console logging middleware for MobX State Tree
This one came about after some work with Redux and redux-logger which beautifully shows actions and state changes as groups in the console window. I thought this was really cool and couldn't find anything comparable in the MobX State Tree world so I posted on the Spectrum group about it to see if anyone else was interested in it.
MST has some conceptual differences from Redux so some of the choices I made around nesting and grouping async calls may not be 100% correct. Im hoping that others will point out issues and help contribute to make it better. So far tho I am using it on our BattleTabs project to great effect.