npm / pinia

pinia

What changed in pinia 4, from its official release notes, upgrade guides and advisories. Sources checked 2026-10-18.

2 breaking1 deprecations2 new APIs and options4 tooling13 fixes and other

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pinia 422 changes

Pinia 4 is ESM only, a technically breaking change for projects using other module formats.
4.0.0release notes
Pinia upgrades to devtools-api v8, which must now be installed alongside pinia.
4.0.0release notes

Errors and dev warnings are refactored with Nostics to make detected problems easier to fix.
4.0.0release notes
Pinia adds a diagnostic for wrong values in plugins.
4.0.0release notes
Settable getters (computed) can now be edited in devtools.
4.0.0release notes
storeToRefs emits a diagnostic for invalid properties.
4.0.0release notes

HMR preserves runtime state of empty placeholder objects.
4.1.0release notes
Shallow refs patched via object syntax now trigger updates.
4.1.0release notes
Testing now notifies shallow refs on initial state.
4.1.0release notes
Nuxt resolves default storesDirs against each layer.
4.1.0release notes
Pinia declares compatibility with Nuxt 5.
4.0.3release notes
During SSR hydration, reactive Set and Map state is replaced instead of unioned.
4.0.3release notes
Types avoid treating a name ending in .vue as reserved.
4.0.3release notes
The production devtools flag is guarded in the distributed output.
4.0.3release notes
Re-add the missing types export so consumers can resolve Pinia's type definitions.
4.0.1release notes
HMR now preserves runtime-added properties of setup store refs.
4.0.0release notes
shouldHydrate now respects the skipHydrate marker on non-plain objects.
4.0.0release notes
storeToRefs gracefully skips nullish values.
4.0.0release notes
Subscribing the same callback twice no longer creates a duplicate watcher.
4.0.0release notes