Industry standard API mocking for JavaScript.

Joined June 2020
The next chapter of MSW is here!
I'm excited to announce MSW v3.0! 🥳 - Leaner dependency graph and smaller size; - ESM-only; - Granular entrypoints; - GraphQL subscriptions; - Socket-based network interception in Node.js; - And much more! mswjs.io/blog/introducing-ms…
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Mock Service Worker 🇺🇦 retweeted
It surprises me how many developers miss the point that you can (and should) generate your handlers in MSW from actual API contracts, like OpenAPI! That *is* the way to drift-free mocking. Please spread the word: mswjs.io/ecosystem/source/ Thank you.
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Mock Service Worker 🇺🇦 retweeted
I am beyond thrilled to welcome @beehiiv as MSW partner! Their support makes sure I can keep working on better API mocking for everyone. Thank you ❤️
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Mock Service Worker 🇺🇦 retweeted
Integrating MSW into Vite-based projects has become silly simple with the new "msw/vite" plugin! And yes, this works with Vitest, too. The plugin integrates MSW client and server-side and keeps the worker script up-to-date for you, automatically.
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Mock Service Worker 🇺🇦 retweeted
Realized I forgot to add the GraphQL subscriptions docs 🤦‍♂️ Injustice fixed. I present to you the beauty which is mocking GraphQL subscriptions: mswjs.io/docs/graphql/interc…
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Help shape the future of API mocking on the web.
With MSW 3.0 released this week, I want to try something new to make the project financially sustainable. I wrote an open letter about the project, its history, and impact on the ecosystem. I ask for five minutes of your time to read it. Thank you. mswjs.io/sponsor
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Mock Service Worker 🇺🇦 retweeted
Come learn tips and tricks of efficient component testing in Vitest from me next week! - Learn how JSDOM works under the hood. - Migrate your tests from JSDOM to Vitest. - Discover how Vitest replaces RTL. Get your tickets 👇 frontkon.tech/events/frontko…
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Mock Service Worker 🇺🇦 retweeted
You don't have to sponsor to help. Consider nominating MSW for the Open Source Endowement fund: endowment.dev/funding/ Thank you!
I am losing roughly $800 a month by working on MSW full-time while it's one of the most used projects in the ecosystem. Please, if MSW provides you any value, consider becoming a sponsor. I mean it when I say every contribution counts. Thank you ❤️ github.com/sponsors/mswjs
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MSW has changed the way everybody mocks their APIs. Please help us make the project sustainable.
I am losing roughly $800 a month by working on MSW full-time while it's one of the most used projects in the ecosystem. Please, if MSW provides you any value, consider becoming a sponsor. I mean it when I say every contribution counts. Thank you ❤️ github.com/sponsors/mswjs
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Mock Service Worker 🇺🇦 retweeted
Come learn component testing from me in person! Accessibility-first, beautifully set up, and running in a real browser with Vitest. One of my best selling workshops on Epic Web now live. 📆 October 5th, 9:00 🇨🇿 Prague More info: frontkon.tech/events/frontko…
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Mock Service Worker 🇺🇦 retweeted
MSW add-on for Storybook is downloaded 1,539,807 times per week! That makes it one of the most used add-ons in the entire Storybook ecosystem. Pretty wild. And with the latest release, it's the best way to mock the network in your stories, too. github.com/mswjs/msw-storybo…
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Mock Service Worker 🇺🇦 retweeted
If you let your agent write component tests for you, you're in BIG trouble. Why? Because agents were trained on prehistoric tests still using JSDOM. Yikes 🤢 Join me on 📆 October 5th in 🇨🇿 Prague for a live workshop to learn component testing in the real browser with Vitest.
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Thank you, Forbes.
I never got to properly thank Forbes for compiling an annual list of companies using MSW. I'm not sure why they stopped at 500, but I'm still grateful!
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Mock Service Worker 🇺🇦 retweeted
No way.
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Mock Service Worker 🇺🇦 retweeted
Just got MSW CI builds from 10m to 1m thanks to @useblacksmith. Absolutely insane, look at this. Also a significant boost after migrating most tests from Playwright to Vitest Browser Mode. It proves times faster for me in every project.
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Mock Service Worker 🇺🇦 retweeted
Hold on, what if...?
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Mock Service Worker 🇺🇦 retweeted
MSW hits another big milestone: 200,000 repositories on GitHub depend on it for their tests and development. Thank you for choosing tools made with care ❤️
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Mock Service Worker 🇺🇦 retweeted
May I have 1 minute of your time? You will not regret it. This is THE testing video I want you all to see. Might be hands-down the best video I've ever recorded.
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Mock Service Worker 🇺🇦 retweeted
Huge news to Storybook developers using MSW: version 3.0 of our add-on has just been released! 🎉 github.com/mswjs/msw-storybo… This brings a new architecture to support both CSF3 and CSF4, fix some long-standing issues, become dependency-free, and a ton more.
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Please help us make v3.0 better: vote on this.
If you're using MSW (@ApiMocking) in @reactnative, would you prefer "msw/native" to automatically include all the necessary polyfills for it to run? (e.g. URL, streams, etc).
61%Yes
39%No
28 votes • Final results
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