immerjs/immer
Create the next immutable state by mutating the current one observed · 2026-08-28
Health v2 · maintenance only
98/100
- Activity 98
- Release rhythm 98
- Longevity 100
How is this computed?
round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10) — computed 2026-09-02. Adoption (stars, forks) is never an input.
- gap_med: 3.5
- age_days: 3169
- days_rel: 14
- days_push: 14
- n_releases_24m: 23
Adoption not part of the score
28980 stars · 880 forks observed · 2026-08-28
What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded
Immer is a tiny JavaScript library that lets you work with immutable state by writing code that mutates a draft copy, producing the next immutable state tree. It is widely used with React state, Redux reducers, and configuration management.
Use cases
- simplify immutable updates in redux reducers
- manage react state without spread boilerplate
- create next immutable state by mutating current one
- detect accidental mutations of state objects
- perform deep updates on nested state trees
- share unchanged parts of state trees in memory
When to choose
- you use React or Redux and want ergonomic immutable updates
- you need efficient structural sharing and change detection
- you want automatic detection of accidental mutations
When to avoid
- your state is small and simple enough that spread operators suffice
- you work outside the JavaScript ecosystem
- you need truly persistent data structures rather than copy-on-write snapshots
Facets
library · maturity stable
state-management serialization frontend web-development developer-tools browser immutable-state redux react copy-on-write javascript nodejs
2 sources
- readme: https://github.com/immerjs/immer · fetched 2026-08-28 · aa4c25aa3b25
- homepage: https://immerjs.github.io/immer/ · fetched 2026-08-29 · 74618fef2263
Member repositories
| Repository | Role | Health v2 |
|---|---|---|
| immerjs/immer | main | 98 |
For agents
Data as of 2026-08-30T08:39:29.467469+00:00 · Report a problem