Mock Service Worker
@mswjs • Industry standard API mocking for JavaScript.. Use this route to separate flagship concentration from portfolio breadth before you treat a publisher as broadly strong.
Portfolio concentration
90%
Top three share
Shows whether the organization is driven by one breakout repo or several visible projects.
Breadth
24 repos
Visible snapshot
11 repositories updated in the last 90 days.
Leading language
TypeScript
Portfolio mix
TypeScript (20), JavaScript (2), Unknown (1)
Average size
927
Stars per repository
Useful for distinguishing one flagship-heavy publisher from a repeatable portfolio.
Updated: 2026-07-17(40d ago)GitHub API fallback24 repositories
90%
of the visible star count comes from this organization's top three repositories.
927
stars per repository in this same snapshot.
TypeScript
is the most common language here, with 11 repositories updated in the last 90 days.
Why this rank
This organization stands out because one flagship repo drives 82% of its visible star count.
Flagship share 82%Breakout repo: msw
Organization pages work best when you separate portfolio breadth from flagship concentration. In Mock Service Worker's case, the visible top three repositories account for about 90% of total stars in this snapshot, which helps explain whether the organization is known for one breakout project or for a broader repeatable portfolio.
The dominant language mix here is TypeScript (20), JavaScript (2), Unknown (1). That makes this page useful not just for popularity checks, but also for seeing what technical shape an organization's public ecosystem actually has.
Top Repositories
| # | Repository | Language | Stars |
|---|---|---|---|
| 1 | mswjs/msw Industry standard API mocking for JavaScript. | TypeScript | 18.2K |
| 2 | mswjs/data Data querying library for testing JavaScript applications. | TypeScript | 1K |
| 3 | mswjs/examples Mock Service Worker usage examples. | 731 | |
| 4 | mswjs/interceptors Low-level network interception library for Node.js. | TypeScript | 681 |
| 5 | mswjs/msw-storybook-addon Mock API requests in Storybook with Mock Service Worker. | TypeScript | 494 |
| 6 | mswjs/playwright Mock APIs in Playwright using Mock Service Worker. | TypeScript | 267 |
| 7 | mswjs/source Generate MSW request handlers from various sources (HAR files, OpenAPI documents, etc). | TypeScript | 218 |
| 8 | mswjs/mswjs.io Official website and documentation for the Mock Service Worker library. | TypeScript | 177 |
| 9 | mswjs/http-middleware Spawn an HTTP server from your request handlers or apply them to an existing server using a middleware. | TypeScript | 126 |
| 10 | mswjs/cloudflare Develop and test Cloudflare applications with Mock Service Worker. | TypeScript | 95 |
| 11 | mswjs/jest-fixed-jsdom A superset of the JSDOM environment for Jest that respects Node.js globals. | JavaScript | 95 |
| 12 | mswjs/headers-polyfill A Fetch API "Headers" polyfill and transformation library. | TypeScript | 33 |
| 13 | mswjs/node-match-path Matches a URL against a path. Parameters, wildcards, RegExp. | TypeScript | 28 |
| 14 | mswjs/cookies Manage request/response cookies in the environments where those are not supported. | TypeScript | 19 |
| 15 | mswjs/storage Persistence and live synchronization layer for testing JavaScript applications. | TypeScript | 19 |
| 16 | mswjs/socket.io-binding Binding to mock Socket.IO connections with Mock Service Worker. | TypeScript | 16 |
| 17 | mswjs/sveltekit Mock API requests in SvelteKit with Mock Service Worker. | JavaScript | 12 |
| 18 | mswjs/is-node-process Reliably determines if the code is running in Node.js. Treats Jest, React Native, Electron, and others like Node.js. | TypeScript | 12 |
| 19 | mswjs/url Utilities for working with URLs. | TypeScript | 6 |
| 20 | mswjs/codemods Automate repetitive and painful MSW migrations & breaking changes. | TypeScript | 5 |
| 21 | mswjs/gh-issue-forms A test repository that is going to disappear. | Shell | 4 |
| 22 | mswjs/msw-github-bot Mock Service Worker community bot. Beep. Bop. | TypeScript | 3 |
| 23 | mswjs/local-storage-polyfill The "localStorage" polyfill for Node.js. | TypeScript | 2 |
| 24 | mswjs/github-webhooks | TypeScript | 1 |
Next step after the organization read
Open a flagship repository, compare a couple of portfolio leaders, or return to the organization map when you want a broader concentration read.
Learn and methodology
Keep trust-building context reachable, but behind the first data read instead of ahead of it.
How to read this organization snapshot
Total stars are useful as a discovery signal, but they do not tell you whether a team maintains every repository equally. Pair this page with release cadence, maintainer activity, and the flagship concentration shown above before making adoption decisions.
For broader background on GitStar's ranking logic and editorial guidance, see Methodology & Editorial Standards.