Confusion between mobx-state-tree and mobx-keystone. When to use which?

Question

Both recommended in the official Mobx page if one wants an opinionated way to using mobx for state management.

Based on these(1,2), keystone seems like an improvement of state-tree. Having everything that state-tree has + more. Nowhere I could find anything that state-tree has that keystone doesn't.

I see keystone is nowhere nearly as mature as state-tree. That's probably the main point stopping me from picking it instead. What are other good points for state-tree over keystone?

P.S. It's going to be used in a React app.

Answer 1

I'm the current maintainer of MobX-State-Tree. I think the primary benefit of MST over MobX-Keystone is that MST is used more widely and has more broad third-party support. For example, mobx-devtools supports MST but not MobX-Keystone, as does Reactotron.

With all that said, I'm very interested in exploring MobX-Keystone for our own usage at my consulting company. Even though I'm maintaining MST, I'm not opposed to MobX-Keystone, and the much better TypeScript support is very tempting. If we end up using it in a project and it goes well, we will likely build in support to Reactotron for it.

I hope this perspective helps.

(With regard to the other answer asking if you really need more than just MobX, it's my opinion that MST and MobX-Keystone bring super useful patterns and tools that help you scale across a whole application in a more cohesive way than remaking them yourself using MobX.)

Answer 2

First ask yourself if you really need those libraries, because you can get really far with just mobx and good ol' OOP patterns. In the official docs you have an example of a store that does auto-saving and serializing.

Having said that, I would go for the mobx-keystone. Typescript works right out of the box, and you can use classes to construct your store, which is IMHO, easier that MST stores. Plus the author is very responsive and he is also a contributor to mobx library.

Answer 3

mobx-keystone is super awesome. After using both of the two libraries for a while I would recommend using it over mobx-state-tree in every possible occasions. It's much more intuitive and easer to learn. It saved a lot of time for my project (switching from zustand to jotai to mobx-keystone, IMO each next one is a bit better than previous one in my use case)

Answer 4

After extensive testing / reading the source code / playing with test suite it feels that mobx-keystone provides a more robust developer experience with Typescript and also has enough escape hatches if you need to work with performance sensitive code. I would implementing a small problem (but complex enough) problem with both libraries to judge for yourself.