Comparing
Create your next immutable state by mutating the current one
TypeScript is a language for application scale JavaScript development
| Metric | immer | typescript |
|---|---|---|
| Ecosystem | npm | npm |
| Difficulty | Beginner | Beginner |
| Weekly downloads | 41.7M | 176.4M↑ |
| Latest version | v11.1.4 | v6.0.2 |
| Recipes | 1 | 1 |
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Use Immer whenever you have deeply nested state updates that are painful to write immutably: Redux reducers, Zustand's set function, or React useState with complex objects. It's built into Redux Toolkit's createSlice, so you're probably already using it.
Use TypeScript for any JavaScript project that will grow beyond a few hundred lines or be worked on by more than one person. The upfront cost of adding types pays back quickly in editor autocomplete, safe refactoring, and catching bugs before runtime.
For flat, simple state (a counter, a boolean toggle), immer's overhead isn't worth it — just spread the object. Immer also has edge cases with classes, Maps, and Sets that require using enableMapSet() and enableAllPlugins().
TypeScript adds a compilation step and a learning curve. For tiny scripts, config files, or throwaway code, plain JavaScript is faster to write. TypeScript's type system also has limits — it can't track runtime behaviour, only the shape of values at compile time.
immer
typescript