MobX
A JavaScript library that tracks state changes automatically and updates the parts of your UI that depend on t
- Stars
- 28.2k
- Forks
- 1.8k
- Licence
- MIT
- Language
- TypeScript
- Last update
- 5 days ago
- Type
- Library
What it is
MobX is a JavaScript and TypeScript library for managing application state. You mark data as observable, and it automatically records which parts of your code read that data, so only the dependent computations or UI components re-run when a value changes. The README says it is used with React through the mobx-react-lite package and that it is not tied to any UI framework.
- Keep a timer or form state in an observable object and have a React component re-render when a single field changes
- Put application logic in plain classes or objects and test them without rendering any UI
- Derive computed values from state so they update automatically when inputs change
Great for
- Frontend developers building React apps with complex or frequently changing state
- Teams who want state logic kept outside UI components so it is easier to test
- Developers who prefer plain JavaScript assignment over action-dispatch boilerplate
- TypeScript projects that want typed reactive state
Not ideal for
- Beginners who want a minimal first project, since the reactivity model takes time to learn
- Projects with very simple state that a plain useState hook or a few variables already handle
- Teams that want a framework-specific, opinionated structure, because the README describes MobX as unopinionated
How to get it
- 1
Install with a package manager
You'll need: Node.js
Install the mobx package
npm install mobx - 2
Run it
- Install mobx and, for React, mobx-react-lite
- Create an observable object with makeAutoObservable
- Wrap a React component with observer so it re-renders on relevant changes
- Update state with plain assignments inside actions
- 3
Get the most out of it
- Use makeAutoObservable to make a model's fields and methods observable with little setup, as shown in the README example
- Wrap React components with observer from mobx-react-lite so rendering tracks state automatically
- Read the full documentation at mobx.js.org for APIs not covered in the truncated README
Downloads
Strengths
- Updates are tracked automatically at runtime, so developers do not write manual memoization or selectors according to the README
- State can be changed with normal JavaScript assignment
- Independent of any UI framework, which makes state code portable and testable
Trade-offs
- The automatic tracking model is a concept new users must learn before it feels natural
- The README excerpt is truncated, so details on advanced APIs and edge cases are not verified here
- Its value depends on how much state complexity the project has; simple apps may not need it
How it compares
| Project | Stars | Type | Level | Updated | Best for |
|---|---|---|---|---|---|
| mobx (this) | 28.2k | Library | intermediate | 5 days ago | Frontend developers building React apps with complex or frequently changing state |
| redux | 61.4k | Library | intermediate | 16 days ago | Developers building larger front-end apps where many components share the same data |
| zustand | 58.9k | Library | beginner | 15 days ago | React developers who want simpler shared state than Redux |
| jotai | 21.3k | Library | beginner | 14 days ago | React developers who want simple shared state without heavy setup |
| Recoil | 19.4k | Library | intermediate | 1.8 years ago | React developers who want shared state beyond simple prop passing |
| cyclejs | 10.2k | Framework | advanced | 5 months ago | Developers who already know reactive streams such as RxJS, xstream, or most.js |
Stats synced from GitHub. The assessment above was drafted with AI from the project's README on 2026-10-29 and may miss recent changes — check the README before relying on a command. MIT licence: free to use, modify and distribute, including commercially, as long as you keep the copyright notice.