* fix tree shaking notworking in webpack bundle ([#1906](https://github.com/vuejs/vuex/issues/1906)) ([1dc2d1f](https://github.com/vuejs/vuex/commit/1dc2d1f21de42138053ea3281dde05487642a76d))
* stop throwing an error on `hasModule` when parent does not exists ([#1850](https://github.com/vuejs/vuex/issues/1850)) ([#1851](https://github.com/vuejs/vuex/issues/1851)) ([12aabe4](https://github.com/vuejs/vuex/commit/12aabe4cc470916d40691097dcb95badb8212f5c))
### Features
***types:** adding logger type for logger plugin ([#1853](https://github.com/vuejs/vuex/issues/1853)) ([cb3198d](https://github.com/vuejs/vuex/commit/cb3198d5998bdb11ef05dfa5ef98d5c5fa873089))
***build:** enable named esm module import on node.js >= 14 ([#1872](https://github.com/vuejs/vuex/issues/1872)) ([acddab2](https://github.com/vuejs/vuex/commit/acddab20769d1bb6125f2da78ac47561c682fc98))
***types:** add missing `logger.d.ts` file to the package ([#1789](https://github.com/vuejs/vuex/issues/1789)) ([a477334](https://github.com/vuejs/vuex/commit/a477334b909913f6a92bdbedcf4a3016a62eab7a))
* warn when unregistering non existing module ([#1786](https://github.com/vuejs/vuex/issues/1786)) ([7cec79d](https://github.com/vuejs/vuex/commit/7cec79d339b874ec41f35891c891dfd27460c1d3))
* include logger plugin to the core export ([#1783](https://github.com/vuejs/vuex/issues/1783)) ([04e2bd8](https://github.com/vuejs/vuex/commit/04e2bd8b3509c67398a6fe73a3d53660069feca8))
***types:** Add `devtools` to store options type ([#1478](https://github.com/vuejs/vuex/issues/1478)) ([38c11dc](https://github.com/vuejs/vuex/commit/38c11dcbaea7d7e661a1623cabb5aef7c6e47ba7))
### Features
* Add `prepend` option for `subscribe` and `subscribeAction` ([#1358](https://github.com/vuejs/vuex/issues/1358)) ([a39d076](https://github.com/vuejs/vuex/commit/a39d0767e4041cdd5cf8050774106c01d39024e0))
***logger:**`createLogger` can optionally log actions ([#987](https://github.com/vuejs/vuex/issues/987)) ([18be128](https://github.com/vuejs/vuex/commit/18be128ad933d1fca6da05c060f7664ce0c819ae))
***types:** avoid broadening vue instance type when using map helpers ([#1639](https://github.com/vuejs/vuex/issues/1639)) ([9a96720](https://github.com/vuejs/vuex/commit/9a9672050bcfee198c379069ec0e1b03ca6cb965))
* add warnings when the different namespaced modules has the same names… ([#1554](https://github.com/vuejs/vuex/issues/1554)) ([91f3e69](https://github.com/vuejs/vuex/commit/91f3e69ed9e290cf91f8885c6d5ae2c97fa7ab81))
* Should vuex mapState print error message [#1093](https://github.com/vuejs/vuex/issues/1093)([#1297](https://github.com/vuejs/vuex/issues/1297)) ([e5ca2d5](https://github.com/vuejs/vuex/commit/e5ca2d52e89a126bd48bd8a6003be77379960ea9))
* Warn about conflicts between state and module ([#1365](https://github.com/vuejs/vuex/issues/1365)) ([538ee58](https://github.com/vuejs/vuex/commit/538ee5803bbca2fc8077208fb30c8d56d8be5cae))
***docs:** Clearify state object type ([#1601](https://github.com/vuejs/vuex/issues/1601)) ([de06f76](https://github.com/vuejs/vuex/commit/de06f76380e7429489c0eb15acc8e0b34a383860))
### Performance Improvements
* Implementing a cache for the gettersProxy object creation ([#1546](https://github.com/vuejs/vuex/issues/1546)) ([4003382](https://github.com/vuejs/vuex/commit/40033825b7259c2e9b702bdf94e0b24ed4511d7c))
* Memory leak happening while using registerModule/u… ([#1508](https://github.com/vuejs/vuex/issues/1508)) ([cb9986a](https://github.com/vuejs/vuex/commit/cb9986ae5a62e002a1d876e881ee5f31dd410888)), closes [issue#1507](https://github.com/issue/issues/1507)
***types:** Make mutation and action payload optional in definition file ([#1517](https://github.com/vuejs/vuex/issues/1517)) ([0e109e2](https://github.com/vuejs/vuex/commit/0e109e2a38dafdc0c2bd6bd3892bc66cfe252b16)), closes [#1491](https://github.com/vuejs/vuex/issues/1491)
### Features
***devtool:** allow usage in non-browser environments ([#1404](https://github.com/vuejs/vuex/issues/1404)) ([665455f](https://github.com/vuejs/vuex/commit/665455f8daf8512e7adbf63c2842bc0b1e39efdb))
***esm build:** build ES modules for browser ([#1533](https://github.com/vuejs/vuex/issues/1533)) ([d7c7f98](https://github.com/vuejs/vuex/commit/d7c7f9844831f98c5c9aaca213746c4ccc5d6929))
***types:** add helpers to default export type declaration as in sources ([#1408](https://github.com/vuejs/vuex/issues/1408)) ([404d0de](https://github.com/vuejs/vuex/commit/404d0de9531322a1a462e53dfd858d20f0bd99af))
***types:** add type annotation for the context of actions ([#1322](https://github.com/vuejs/vuex/issues/1322)) ([d1b5c66](https://github.com/vuejs/vuex/commit/d1b5c66961ab53e0172cbc706ff616227bcb5c77))
***types:** allow a function type for root `state` option ([#1132](https://github.com/vuejs/vuex/issues/1132)) ([d39791b](https://github.com/vuejs/vuex/commit/d39791bd05830b1889705761ef5779449e35e97f))
* Add key to v-for ([#1369](https://github.com/vuejs/vuex/issues/1369)) ([a9bd047](https://github.com/vuejs/vuex/commit/a9bd047ea147cacfcb4003946aeebccd2c5e1e4e))
* avoid to call root state function twice ([#1034](https://github.com/vuejs/vuex/issues/1034)) ([86677eb](https://github.com/vuejs/vuex/commit/86677ebcbfaecf712f339b73a568150fc9fd5f5e))
* fix [#1032](https://github.com/vuejs/vuex/issues/1032), relax vue typing in helpers ([#1044](https://github.com/vuejs/vuex/issues/1044)) ([7c7ed1d](https://github.com/vuejs/vuex/commit/7c7ed1d37ee8a5058082d763d80529e5fef86a0b))
### Features
* add ability to turn off devtools on vuex by passing an off options ([#1407](https://github.com/vuejs/vuex/issues/1407)) ([be75d41](https://github.com/vuejs/vuex/commit/be75d41cf54d50177a7db7e9218e8d1c820ae830))
* ensure errors in action subscribers do not break actions ([acd7249](https://github.com/vuejs/vuex/commit/acd72492eaffff3661f75860a3d7ab37b73c3906))
***typings:** adapt to the new Vue typings ([#909](https://github.com/vuejs/vuex/issues/909)) ([65dbfec](https://github.com/vuejs/vuex/commit/65dbfec40d5fe7aac05aab333c7b70768997ca7f))
### BREAKING CHANGES
***typings:** It is no longer compatible with the old Vue typings
* chore(package): bump typescript and vue core typings
* initialize root state as an empty object if state function returns no value ([#927](https://github.com/vuejs/vuex/issues/927)) ([0e9756b](https://github.com/vuejs/vuex/commit/0e9756b93c5de8e03286d93f0b50af5f8dfd3bac))
### Features
* add logger plugin logger config support ([#771](https://github.com/vuejs/vuex/issues/771)) ([804c3bb](https://github.com/vuejs/vuex/commit/804c3bbd2e60f11412f5a7cb7694969f8f6c215c))
* preserve state with registerModule ([#837](https://github.com/vuejs/vuex/issues/837)) ([4c1841e](https://github.com/vuejs/vuex/commit/4c1841e79e63ca0ca95d0cc1b218fde258f23c20))
* root actions in namespaced modules ([#941](https://github.com/vuejs/vuex/issues/941)) ([73189eb](https://github.com/vuejs/vuex/commit/73189eb35509de7d49bd2b577900ad560d37dcb0))
* allow installation on extended Vue copies ([c87b72f](https://github.com/vuejs/vuex/commit/c87b72f2ff7f65e708c4b59a752ef234d0f28d1f))
* link to details of mutations in components ([#930](https://github.com/vuejs/vuex/issues/930)) ([e82782b](https://github.com/vuejs/vuex/commit/e82782ba81c398dd5b78a195257a9d1c3a6d85ef))
* move auto installation code into the store constructor ([#914](https://github.com/vuejs/vuex/issues/914)) ([852ac43](https://github.com/vuejs/vuex/commit/852ac43ea4813ecaeb1e5106c4a29c74e57c2fd7))
### Features
* allow to passing functions in mapActions/mapMutations (fix [#750](https://github.com/vuejs/vuex/issues/750)) ([#924](https://github.com/vuejs/vuex/issues/924)) ([be15f32](https://github.com/vuejs/vuex/commit/be15f32c0077d8fe9bafa38c1b319b655cfd5f86))
***typings:** watch() returns an unwatch function ([#922](https://github.com/vuejs/vuex/issues/922)) ([a4bd081](https://github.com/vuejs/vuex/commit/a4bd0816838cc4a843d833363b9aa412c1256e5e))
* add missing typings and docs of createNamespacedHelpers ([#910](https://github.com/vuejs/vuex/issues/910)) ([7ad573b](https://github.com/vuejs/vuex/commit/7ad573bba59d23dbd66e3a25e6614296aeb98d42))
### Features
***store:** bind mutation and action handlers to store ([#872](https://github.com/vuejs/vuex/issues/872)) ([67da622](https://github.com/vuejs/vuex/commit/67da6225552e46266ed059c7f0d0128294cd08ed))
### Performance Improvements
* do not connect devtools if Vue.config.devtools == false ([#881](https://github.com/vuejs/vuex/issues/881)) ([dd7f817](https://github.com/vuejs/vuex/commit/dd7f8178d93e6121a447c410b9c652f40cd80937))
:fire: **HEADS UP!** You're currently looking at Vuex 3 branch. If you're looking for Vuex 4, [please check out `4.0` branch](https://github.com/vuejs/vuex/tree/4.0).
---
Vuex is a state management pattern + library for Vue.js applications. It serves as a centralized store for all the components in an application, with rules ensuring that the state can only be mutated in a predictable fashion. It also integrates with Vue's official [devtools extension](https://github.com/vuejs/vue-devtools) to provide advanced features such as zero-config time-travel debugging and state snapshot export / import.
Learn more about Vuex at "[What is Vuex?](https://vuex.vuejs.org/)", or get started by looking into [full documentation](http://vuex.vuejs.org/).
## Documentation
To check out docs, visit [vuex.vuejs.org](https://vuex.vuejs.org/).
For questions and support please use the [Discord chat server](https://chat.vuejs.org) or [the official forum](http://forum.vuejs.org). The issue list of this repo is **exclusively** for bug reports and feature requests.
## Issues
Please make sure to read the [Issue Reporting Checklist](https://github.com/vuejs/vuex/blob/dev/.github/contributing.md#issue-reporting-guidelines) before opening an issue. Issues not conforming to the guidelines may be closed immediately.
## Changelog
Detailed changes for each release are documented in the [release notes](https://github.com/vuejs/vuex/releases).
## Stay In Touch
For latest releases and announcements, follow on Twitter: [@vuejs](https://twitter.com/vuejs).
## Contribution
Please make sure to read the [Contributing Guide](https://github.com/vuejs/vuex/blob/dev/.github/contributing.md) before making a pull request.