# Vitest v4.0.15 — Release & Upgrade Intelligence
- **Product:** Vitest (https://vitest.dev)
- **Version:** v4.0.15
- **Released:** Dec 02, 2025
- **Impact Score:** 5/10
- **Breaking Changes:** Not verified
- **Canonical Analysis:** https://changelogs.us/vitest/updates/v4.0.15/

## Executive Summary (TL;DR)
Vitest v4.0.15. Source highlight:    🚀 Experimental Features

## New Features
- **reporters**: Print import duration breakdown &nbsp;-&nbsp; by @sheremet-va in https://github.com/vitest-dev/vitest/issues/9105 <samp>(122ff)</samp>

## Bug Fixes
- **cache**: Add opt-out on a plugin level, fix internal root cache &nbsp;-&nbsp; by @sheremet-va in https://github.com/vitest-dev/vitest/issues/9154 <samp>(a68f7)</samp>
- Keep built-in id as is in bun and deno &nbsp;-&nbsp; by @sheremet-va in https://github.com/vitest-dev/vitest/issues/9117 <samp>(075ab)</samp>
- Use `optimizeDeps.rolldownOptions` to fix depreated warning + fix `ssr.external: true` &nbsp;-&nbsp; by @hi-ogawa in https://github.com/vitest-dev/vitest/issues/9121 <samp>(fd8bd)</samp>
- Fix external behavior with `deps.optimizer` &nbsp;-&nbsp; by @hi-ogawa in https://github.com/vitest-dev/vitest/issues/9125 <samp>(4c754)</samp>
- Very minor typo in "Chrome DevTools Protocol" &nbsp;-&nbsp; by @HowToTestFrontend in https://github.com/vitest-dev/vitest/issues/9146 <samp>(20997)</samp>
- **browser**: Run `toMatchScreenshot` only once when used with `expect.element` &nbsp;-&nbsp; by @macarie in https://github.com/vitest-dev/vitest/issues/9132 <samp>(0d2e7)</samp>