/pinia

name: pinia
description: Pinia official Vue state management library, type-safe and extensible. Use when defining stores, working with state/getters/actions, or implementing store patterns in Vue apps.
metadata:
  author: Anthony Fu
  version: "2026.9.25"
  source: Generated from https://github.com/vuejs/pinia, scripts located at https://github.com/antfu/skills

Pinia

Pinia is the official state management library for Vue, designed to be intuitive and type-safe. It supports both Options API and Composition API styles, with first-class TypeScript support and devtools integration.

> The skill is based on Pinia v4.0.3, generated at 2026-09-25.

Core References

| Topic | Description | Reference | |-------|-------------|-----------| | Stores | Defining stores, state, getters, actions, storeToRefs, subscriptions | [core-stores](references/core-stores.md) |

Features

Extensibility

| Topic | Description | Reference | |-------|-------------|-----------| | Plugins | Extend stores with custom properties, state, and behavior | [features-plugins](references/features-plugins.md) |

Composability

| Topic | Description | Reference | |-------|-------------|-----------| | Composables | Using Vue composables within stores (VueUse, etc.) | [features-composables](references/features-composables.md) | | Composing Stores | Store-to-store communication, avoiding circular dependencies | [features-composing-stores](references/features-composing-stores.md) |

Best Practices

| Topic | Description | Reference | |-------|-------------|-----------| | Testing | Unit testing with @pinia/testing, mocking, stubbing | [best-practices-testing](references/best-practices-testing.md) | | Outside Components | Using stores in navigation guards, plugins, middlewares | [best-practices-outside-component](references/best-practices-outside-component.md) |

Advanced

| Topic | Description | Reference | |-------|-------------|-----------| | SSR | Server-side rendering, state hydration | [advanced-ssr](references/advanced-ssr.md) | | Nuxt | Nuxt integration, auto-imports, SSR best practices | [advanced-nuxt](references/advanced-nuxt.md) | | HMR | Hot module replacement for development | [advanced-hmr](references/advanced-hmr.md) |

Key Recommendations

• **Prefer Setup Stores** for complex logic, composables, and watchers
• **Use `storeToRefs()`** when destructuring state/getters to preserve reactivity
• **Actions can be destructured directly** - they're bound to the store
• **Call stores inside functions** not at module scope, especially for SSR
• **Add HMR support** to each store for better development experience
• **Use `@pinia/testing`** for component tests with mocked stores