AriPerkkio
@ariperkkio.dev
๐ค 1222
๐ฅ 185
๐ 88
@vitest.dev
Core Team โข Open Source
@chromatic.com
โข github.com/AriPerkkio
This day 4 years ago I sent my first PR to
@vitest.dev
. Back then it was on v0.7.4 with 80K weekly downloads. After one year and +70 more PRs,
@antfu.me
and
@erus.dev
invited me to join the team. Today we are at v4.1.0 with 35M weekly downloads. Maybe in 2030 we'll have Vitest 8 with 140M downloads.
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test(reporters): add outputFile tests by AriPerkkio ยท Pull Request #978 ยท vitest-dev/vitest
Adds missing test cases for outputFile configuration. I'm working on another bug fix and thought let's merge these ones first.
https://github.com/vitest-dev/vitest/pull/978
14 days ago
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reposted by
AriPerkkio
Younes Jaaidi
16 days ago
I just need a few more of you to migrate to
@vitest.dev
so I can prove that crystal balls work ๐ฎ ๐ (the charts from
npmx.dev
are so neat โค๏ธ)
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reposted by
AriPerkkio
VoidZero
about 1 month ago
Flaky tests and memory leaks are the worst.
@vitest.dev
now has a flag that catches uncleared intervals, lingering servers, and other async operations leaking across your tests. Available in the latest 4.1 beta. Big shout out to
@ariperkkio.dev
from the Vitest team for landing this PR! ๐ฅ
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In the next version of Vitest you can track leaking asynchronous resources via `--detect-async-leaks` option! Available in v4.1.0-beta.4 release. ๐ (notice missing await in the example)
about 1 month ago
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Excited to announce that I've officially joined
@chromatic.com
! My main focus will be working around features related to
@vitest.dev
๐ค
about 2 months ago
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I'd like to avoid forking Istanbuljs monorepo just for Vitest. Any istanbuljs Github organization members here who could make me a maintainer there? (
@kentcdodds.com
,
@jasonkurian.dev
๐)
github.com/vitest-dev/v...
3 months ago
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reposted by
AriPerkkio
VoidZero
3 months ago
Vitest hit 20 million weekly downloads in December, right before Christmas break. To put that into context: 5 million
@vitest.dev
weekly downloads were reached in June 2024, meaning a 4x increase in just 1.5 years. ๐
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When using vite@8-beta with Vitest users no longer need to add magical '@preserve' keywords in their coverage ignore hints. Originally this work-around was needed due to esbuild's (intentional) lack of support for comment preserving. Oxc has built-in support for JS coverage tools' ignore hints.
4 months ago
0
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reposted by
AriPerkkio
Vladimir
4 months ago
Vitest 4.0.11 adds an experimental `fsModuleCache` flag to cache module transforms between reruns. Learn more:
vitest.dev/config/exper...
This is an opt-in feature, please let us know how it works for you! And example of a single test file that imports a lot of files (~1500). Almost a 50% boost!
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reposted by
AriPerkkio
danielroe ๐บ๐ฆ
5 months ago
โก ever wanted to download
@stackblitz.com
projects without opening the site? you now can ๐ ๐ web: replace
stackblitz.com
w/
stackblitz.zip
in any edit url ๐ฅ๏ธ cli: `npx stackblitz-zip <url>` or `npx stackblitz-clone <url>` ๐ฆ npm: `npm i stackblitz-zip` built for myself to grab repros from issues
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Excited to see Typesafe CSF factories solve RFC I wrote two years ago. No more explicit TS typings!
github.com/storybookjs/...
add a skeleton here at some point
5 months ago
0
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reposted by
AriPerkkio
5 months ago
My talk slides are available here
hiroshi-talks.vercel.app/2025-10-25/1
also with source code in
github.com/hi-ogawa/talks
It was a great experience to talk with many awesome folks in person! Thanks
@vuefes.bsky.social
for the opportunity!
add a skeleton here at some point
0
14
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reposted by
AriPerkkio
Vitest
5 months ago
Vitest 4 is out! - Browser Mode is Stable - Visual Regression Testing - Improved Debugging - Pool Stabilization - New APIs - Bug Fixes Stay updated with our blog post:
vitest.dev/blog/vitest-4
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Announcing Vitest 4.0
Vitest 4.0 Release Announcement
https://vitest.dev/blog/vitest-4
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After maintaining Tinypool for over 2 years I'm happy to see next version of Vitest dropping it. I've written some reasoning about this in the linked PR. Even though this change is significant for Vitest, I'm more confident about it than making new changes in Tinypool.
github.com/vitest-dev/v...
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feat!: rewrite pools without `tinypool` by AriPerkkio ยท Pull Request #8705 ยท vitest-dev/vitest
Description Removes Tinypool and adds new custom internal pool for Vitest only. Some previous thoughts I wrote ~2 months ago about this below. Vitest uses tinypool for orchestrating how test file...
https://github.com/vitest-dev/vitest/pull/8705
5 months ago
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27
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reposted by
AriPerkkio
VoidZero
5 months ago
VoidZero's
@erus.dev
talks about the upcoming
@vitest.dev
features including the new report API and multi-browser configuration as well as what to expect in Vitest 4 ๐งช Full video in comments
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reposted by
AriPerkkio
VoidZero
6 months ago
Watch VoidZeroโs
@overlookmotel.bsky.social
explain how oxlint tackles JS-Rust interoperability to maintain high performance for plugins. Full video in comment ๐
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Setting custom `process.title` in Node takes around 10-20ms. Vitest used to do this for every isolated test file so that debugging test runner processes was a bit nicer experience. But it's not worth the performance hit.
add a skeleton here at some point
7 months ago
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reposted by
AriPerkkio
sapphi_red
8 months ago
Published a post I started writing half a year ago. Make sure to use the latest versions of each build tools and configure the settings appropriately!
green.sapphi.red/blog/address...
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Addressing Source Code Leaks Across the Ecosystem โ A Retrospective
https://green.sapphi.red/blog/addressing-source-code-leaks-across-the-ecosystem-a-retrospective
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reposted by
AriPerkkio
Storybook
10 months ago
Our latest post walks through how to use the coverage reporting in Storybook 9 to be sure your components are well-tested.
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Frontend test coverage with Storybook 9
Stories give you free test coverage
https://storybook.js.org/blog/frontend-test-coverage-with-storybook-9/
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We've added new coverage provider comparison page on Vitest documentation. This guide describes the lower level differences between Istanbul and V8. It should help users choosing which provider to use.
vitest.dev/guide/covera...
10 months ago
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AST based V8 code coverage is finally here! I thought of this feature first time over 2 years ago, but knew it would require so much work that I couldn't finish it by working on Vitest just on weekends. Ever since
@stackblitz.com
hired me to work on Vitest I knew I could finish features like this.
add a skeleton here at some point
10 months ago
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reposted by
AriPerkkio
Vitest
10 months ago
Vitest 3.2 is out! - New Annotations API - Scoped Fixtures - Custom Browser Locators API - Test Signal - Better V8 Coverage Result And many more features!
vitest.dev/blog/vitest-...
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Onboarding on new
@storybook.js.org
projects is just perfect. So nice to have testing setup *covered* out-of-the-box. ๐ค
11 months ago
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reposted by
AriPerkkio
Open Source Pledge โ
11 months ago
@bolt.new
are looking for an engineer to advance web computing by working on WebContainer, the first in-browser WebAssembly-based operating system. You'd be getting paid to be an Open Source contributor, AND you'd get to work with
@patak.dev
. Sounds pretty good to us!
opensourcepledge.com/jobs/
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Tinypool is now built with tsdown! Migration from tsup was smooth and required minimal changes. Thanks to
@sxzz.dev
๐ฏ
11 months ago
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After couple of days looking at *.cpuprofile's, I think it's getting closer to stable v1 release. The ~3MB checker.ts from Typescript repo is perfect benchmarking reference for tools that process source code. When generating coverage for 'vuejs/core' repo, speed is close to original v8-to-istanbul.
add a skeleton here at some point
12 months ago
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This release includes long-awaited "--silent=passed-only" option, that can be used to hide console.log calls from passing tests. Only the logs from failing tests are reported.
add a skeleton here at some point
about 1 year ago
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Finalizing rewrite of AST-aware v8-to-istanbul. This will provide accuracy of Istanbul coverage for V8 coverage reports. I've intentionally kept this tool unopinionated so that it's not strictly tied to just
@vitest.dev
- it should be usable with Jest, C8, Playwright and node:test too.
about 1 year ago
1
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reposted by
AriPerkkio
ViteConf
about 1 year ago
We are proud to announce the First Ever ViteConf taking place in person ๐คฉ Join the Creator of Vite,
@evanyou.me
, Core Team, Ecosystem Authors and Experts! ๐ 10 October, Amsterdam ๐ Sign up for the waiting list to be notified about the ticket release via
viteconf.org
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reposted by
AriPerkkio
about 1 year ago
Huge improvement for Vitest development workflow, thanks to isolated declaration! I didn't think the migration was possible until I see PRs by
@sxzz.dev
. Just started to sponsor Kevin for the amazing work!
add a skeleton here at some point
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Tree-view of
@vitest.dev
verbose reporter is coming back! We (well I did) forgot to implement this during v3's reporter rewrites. I had already forgot how good it looks.
about 1 year ago
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reposted by
AriPerkkio
bolt.new
about 1 year ago
In 2025, weโre doubling down on our support to Open Source. Weโre thrilled to announce the Bolt 100K Open Source Fund:
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Bolt 100K Open Source Fund
We're doubling down on our support to Open Source in 2025 with a 100K fund targeted at web infrastructure and Bolt dependencies.
https://blog.stackblitz.com/posts/bolt-100k-oss-fund/
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reposted by
AriPerkkio
Mohammad Bagher ๐พ
about 1 year ago
๐ค it's a good day for tinypool! thank you so much
@sebastienlorber.com
and
@ariperkkio.dev
โค๏ธ
github.com/facebook/doc...
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feat(core): Docusaurus Faster - SSG worker threads by slorber ยท Pull Request #10826 ยท facebook/docusaurus
Motivation This PR introduces a new Docusaurus Faster option: siteConfig.future.experimental_faster.ssgWorkerThreads. It permits you to optimize the static site generation phase of your site, by ex...
https://github.com/facebook/docusaurus/pull/10826
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Huge thanks to
@sapphi.red
for helping the
@vitest.dev
team with these findings. Perfect collaboration between projects. ๐ค
add a skeleton here at some point
about 1 year ago
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reposted by
AriPerkkio
patak
about 1 year ago
I finally met
@ariperkkio.dev
! And he got his first edition vitest shirt, that has been waiting for him for a year at home
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reposted by
AriPerkkio
patak
about 1 year ago
everything is better with open source friends
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Installing dependencies while coding offline in an airplane. The --prefer-offline from
@pnpm.io
is just perfect. ๐คฉ
about 1 year ago
1
12
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reposted by
AriPerkkio
Joachim Viide
about 1 year ago
Expressing appreciation for โชthe work of
@ariperkkio.dev
โฌ and the other
@vitest.dev
devs. The absolute smoothness of Vitest 3.0's terminal reporter is something I didn't even realize I needed.
add a skeleton here at some point
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reposted by
AriPerkkio
bolt.new
about 1 year ago
Today we're announcing $105.5m in funding to take Bolt to new heights! ๐ Our Series B was led by Emergence & GV, with participation from Madrona, The Chainsmokers (Mantis), Conviction, and some of the best operators building in devtools & AI
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reposted by
AriPerkkio
James
about 1 year ago
we've now migrated parse5 to use
@vitest.dev
๐ big thanks to
@ariperkkio.dev
for help along the way too
0
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reposted by
AriPerkkio
Anthony Fu
about 1 year ago
I love the
@vitest.dev
v3's new reporter! The team is doing incredible work! ๐๐ฅ
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Smooth terminal reporters, new Node APIs, new Reporter APIs, inline Workspaces and much more! So happy to see all these features finally out. I think this was the most demanding major release so far. ๐ฅณ
add a skeleton here at some point
about 1 year ago
0
35
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reposted by
AriPerkkio
Vladimir
about 1 year ago
Working on the new
@vitest.dev
reporter API gif by
@ariperkkio.dev
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AriPerkkio
Dominic Elm
about 1 year ago
๐ Thrilled to announce my interactive
#WebAssembly
course! Learn WebAssembly from the ground up with: ๐ Custom-built debugger & VM ๐ Live stack & memory insights ๐ป Hands-on exercises ๐ ๏ธ Build real projects Level up with WebAssembly! โจ ๐
learn-wasm.dev
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Learn WebAssembly
Take your programming skills to the next level with this comprehensive, code-first, and hands-on WebAssembly course - the ultimate gateway to mastering the fundamentals of this revolutionary technolog...
https://learn-wasm.dev
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reposted by
AriPerkkio
James
over 1 year ago
We've opened a new tinylibs discord! This should help give us a space to collab more on feedback and new libraries
discord.gg/TwSXGv6rqM
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Join the tinylibs Discord Server!
The tinylibs community server | 5 members
https://discord.gg/TwSXGv6rqM
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This kind of growth just amazes me. On 12/2023 Vitest had 3M weekly downloads. Now in 12/2024 there's almost 8M. Maybe we can share #2 with Storybook next year! ๐
2024.stateofjs.com/en-US/librar...
over 1 year ago
3
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reposted by
AriPerkkio
Vladimir
over 1 year ago
The beta has started!
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Release v3.0.0-beta.1 ยท vitest-dev/vitest
We decided to skip Vitest 2.2 and release Vitest 3 with support for Vite 6 instead. There will be no more Vitest 2 versions. Vitest 3 is the first version that supports Vite 6 (excluding 2.1.6) We ...
https://github.com/vitest-dev/vitest/releases/tag/v3.0.0-beta.1
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reposted by
AriPerkkio
Dominic Elm
over 1 year ago
If you like what we are doing on
bolt.new
, we are hiring. I'd love to talk to you. If you're interested, feel free to send me a DM.
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bolt.new
Prompt, run, edit & deploy web apps
http://bolt.new
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reposted by
AriPerkkio
Younes Jaaidi
over 1 year ago
โก๏ธ Yes! Vitest is generally faster than Jest -- but is feedback speed the only factor that matters? If you are still on the fence about switching to Vitest, here are 15+ reasons that will convince you! ๐
cookbook.marmicode.io/angular/why-...
#javascript
#angular
#testing
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reposted by
AriPerkkio
TutorialKit
over 1 year ago
pnpm create tutorial
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