Comparison with Immer
Mutative is a high-performance immutable update library, and Immer is a popular immutable update library. This page compares the differences between Mutative and Immer.
Difference between Mutative and Immer
| Mutative | Immer | |
|---|---|---|
| Custom shallow copy | ✅ | ❌ |
| Strict mode | ✅ | ❌ |
| No data freeze by default | ✅ | ❌ |
| Non-invasive marking | ✅ | ❌ |
| Complete freeze data | ✅ | ❌ |
| Non-global config | ✅ | ❌ |
| async draft function | ✅ | ❌ |
| Fully compatible with JSON Patch spec | ✅ | ❌ |
| new Set methods(Mutative v1.1.0+) | ✅ | ❌ |
Mutative has fewer bugs such as accidental draft escapes than Immer, view details.
Mutative vs Immer Performance
Mutative passed all of Immer's test cases.
Measure(ops/sec) to update 50K arrays and 1K objects, bigger is better(view source). [Mutative v1.1.0 vs Immer v10.1.1]
Naive handcrafted reducer - No Freeze x 4,670 ops/sec ±0.64% (96 runs sampled)
Mutative - No Freeze x 6,747 ops/sec ±0.61% (95 runs sampled)
Immer - No Freeze x 5.65 ops/sec ±1.53% (19 runs sampled)
Mutative - Freeze x 1,062 ops/sec ±0.74% (95 runs sampled)
Immer - Freeze x 394 ops/sec ±0.85% (93 runs sampled)
Mutative - Patches and No Freeze x 1,011 ops/sec ±0.24% (98 runs sampled)
Immer - Patches and No Freeze x 5.64 ops/sec ±0.22% (19 runs sampled)
Mutative - Patches and Freeze x 545 ops/sec ±1.19% (94 runs sampled)
Immer - Patches and Freeze x 215 ops/sec ±0.70% (86 runs sampled)
The fastest method is Mutative - No Freeze
Run yarn benchmark to measure performance.
OS: macOS 14.7, CPU: Apple M1 Max, Node.js: v22.11.0
Immer relies on auto-freeze to be enabled, if auto-freeze is disabled, Immer will have a huge performance drop and Mutative will have a huge performance lead, especially with large data structures it will have a performance lead of more than 50x.
So if you are using Immer, you will have to enable auto-freeze for performance. Mutative is disabled auto-freeze by default. With the default configuration of both, we can see the 17x performance gap between Mutative (6,747 ops/sec) and Immer (394 ops/sec).
Overall, Mutative has a huge performance lead over Immer in more performance testing scenarios. Run yarn performance to get all the performance results locally.