crossws
Cross-platform WebSocket Servers for Node.js, Deno, Bun and Cloudflare Workers
About
Cross-platform WebSocket Servers for Node.js, Deno, Bun and Cloudflare Workers
Live mirror of the GitHub README. Updated whenever the repo's default branch changes.
crossws
Elegant, typed, and simple toolkit to implement cross-platform WebSocket servers.
Features
🧩 Seamlessly integrates with Bun, Cloudflare Workers, Deno and Node.js and any compatible web framework.
✅ Prebundled with ws for Node.js support with alternative/much faster uWebSockets adapter.
📦 Extremely lightweight and tree-shakable conditional ESM exports.
🚀 High-performance and simple hooks API, without per-connection callback creation.
🌟 Typed hooks API and developer-friendly object inspection.
Contribution
Local development
License
Published under the MIT license.
Made by @pi0 and community 💛
🤖 auto updated with automd
Quick facts
npm install crosswsCommon pairings
Packages this one expects to find in the same project. Each is also a Sourcemap Explorer detection target.
How Sourcemap Explorer detects crossws
We catch crossws from two complementary signals: bundled source paths and the embedded package.json. Modern bundlers (webpack, Vite, esbuild, Rollup, Turbopack) preserve the original node_modules/crossws/ paths inside the JavaScript sourcemap's sources[] array — that's the canonical signal. When the matching package.json is also captured in sourcesContent[], we read the exact version field — patch number included. No regex guessing, no version inference.
- 1
Confirm the site exposes sourcemaps
In DevTools Network, check the response headers of any application script for `SourceMap` or `X-SourceMap`. Failing that, fetch the script's last 4 KB and look for a `//# sourceMappingURL=` comment.
- 2
Find the package in the bundle
Open DevTools → Network → reload. Click any application script and look at its sourcemap. Inside, search `sources[]` for entries matching `node_modules/crossws/` — every match confirms the package is bundled. The matching `sourcesContent[i]` for `node_modules/crossws/package.json` gives you the exact installed version.
- 3
Read the version directly from package.json
Run `jq -r '. as $m | $m.sources | to_entries[] | select(.value | endswith("node_modules/crossws/package.json")) | $m.sourcesContent[.key] | fromjson | .version' bundle.js.map`. Sourcemap Explorer automates the same query in the popup.
Recent versions
FAQ
What is crossws used for?
Cross-platform WebSocket Servers for Node.js, Deno, Bun and Cloudflare Workers
How can I tell if a website is using crossws?
Open the page in Chrome with the Sourcemap Explorer extension installed and read the Stack tab. We catch `crossws` from two complementary signals: `node_modules/crossws/` paths inside the JavaScript sourcemap, and the embedded `package.json` we read for exact-version detection. Without the extension you can do the same lookup manually in DevTools — the steps are listed in the "How Sourcemap Explorer detects" section above.
What is the latest version of crossws?
0.4.5, as published on the npm registry. The "Recent versions" table on this page lists the most recent 8 releases with their release dates. Sourcemap Explorer reports the version actually bundled into a site, which can lag the latest release by months on real-world deployments.
Where can I read more?
Project homepage: https://crossws.h3.dev. Source code: https://github.com/h3js/crossws. Published on npm: https://www.npmjs.com/package/crossws. Licensed as MIT.
Detected by Sourcemap Explorer
When a bundle ships sourcemaps, we read the embedded package.json for crossws and report the precise version. Without sourcemaps, an import / require in the page's scripts is enough to flag it.