# Vitest v1.0.0 — Release & Upgrade Intelligence
- **Product:** Vitest (https://vitest.dev)
- **Version:** v1.0.0
- **Released:** Dec 04, 2023
- **Impact Score:** 7/10
- **Breaking Changes:** Source flagged
- **Canonical Analysis:** https://changelogs.us/vitest/updates/v1.0.0/

## Executive Summary (TL;DR)
Vitest v1.0.0. Source highlight: Vitest 1.0 is here! This release page lists all changes made to the project during the beta. For the migration guide, please refer to the documentation.

## Breaking Changes & Deprecations
- &nbsp;&nbsp;&nbsp;🚨 Breaking Changes - Add support for `pool` and `poolOptions`, remove old flags &nbsp;-&nbsp; by @AriPerkkio in https://github.com/vitest-dev/vitest/issues/4172 [<samp>(114a9)</samp>](https://github.com/vitest-dev/vitest/commit/114a993c)

## New Features
- Add support for `pool` and `poolOptions`, remove old flags &nbsp;-&nbsp; by @AriPerkkio in https://github.com/vitest-dev/vitest/issues/4172 <samp>(114a9)</samp>
- Add Marko example and include code coverage for Marko files &nbsp;-&nbsp; by @DylanPiercey in https://github.com/vitest-dev/vitest/issues/4263 <samp>(eac77)</samp>
- Update magic-string &nbsp;-&nbsp; by @bluwy in https://github.com/vitest-dev/vitest/issues/4345 <samp>(fde18)</samp>
- Implement provide/inject API to transfer data from the main thread &nbsp;-&nbsp; by @sheremet-va in https://github.com/vitest-dev/vitest/issues/4422 <samp>(a7522)</samp>
- Improve expectTypeOf error messages &nbsp;-&nbsp; by @mmkal, **Misha Kaletsky** and @sheremet-va in https://github.com/vitest-dev/vitest/issues/4206 <samp>(18300)</samp>
- Add test.sequential() api &nbsp;-&nbsp; by @dsyddall in https://github.com/vitest-dev/vitest/issues/4512 <samp>(c3619)</samp>

## Improvements
- Remove EnhancedSpy type, deprecate SpyInstance, improve mocks and vi documentation &nbsp;-&nbsp; by @sheremet-va and @dammy001 in https://github.com/vitest-dev/vitest/issues/4400 <samp>(d40b3)</samp>
- Update `log-update` v9 &nbsp;-&nbsp; by @AriPerkkio in https://github.com/vitest-dev/vitest/issues/4390 <samp>(ba1df)</samp>
- Close pool early in run-mode &nbsp;-&nbsp; by @AriPerkkio in https://github.com/vitest-dev/vitest/issues/4623 <samp>(e0e20)</samp>
- **coverage-istanbul**: `all: true` instruments already instrumented files &nbsp;-&nbsp; by @AriPerkkio in https://github.com/vitest-dev/vitest/issues/4552 <samp>(d1e1b)</samp>

## Bug Fixes
- Add multiple globals in VM+JSDOM &nbsp;-&nbsp; by @nstepien in https://github.com/vitest-dev/vitest/issues/4199 and https://github.com/vitest-dev/vitest/issues/4202 <samp>(fc947)</samp>
- Ignore "plugins" field in snapshotFormat option &nbsp;-&nbsp; by @sheremet-va in https://github.com/vitest-dev/vitest/issues/4204 <samp>(db1ff)</samp>
- `nextTick` mocking error message to mention correct config option &nbsp;-&nbsp; by @AriPerkkio in https://github.com/vitest-dev/vitest/issues/4215 <samp>(98fe3)</samp>
- Export VitestUtils interface &nbsp;-&nbsp; by @fbritoferreira in https://github.com/vitest-dev/vitest/issues/4301 <samp>(b1439)</samp>
- Assertion diff message handle non-writable sub-properties &nbsp;-&nbsp; by @bfamchon in https://github.com/vitest-dev/vitest/issues/4278 <samp>(7e1a0)</samp>
- Don't bundle import from rollup &nbsp;-&nbsp; by @sheremet-va in https://github.com/vitest-dev/vitest/issues/4392 <samp>(3b584)</samp>