Why we built this
Hiring engineers is hard, and the tools don't help. Most interview platforms are closed boxes. You can't see how they run candidate code, you can't change them to fit how you work, and you end up using one tool for live interviews, another for take-homes, and a spreadsheet to track it all.
We wanted one platform that does all of it: live interviews, async screening, and take-homes. One that runs candidate code out in the open, and that you can read, fork, and host yourself. So we built CoderScreen and made it open source.
If you've ever spent a night reading half-finished take-homes, or sat through an hour-long interview with someone who couldn't get past FizzBuzz, this is for you.
What you get
A live editor candidates actually like. Everyone codes in the same editor in real time, with live cursors. Candidates just click a link to join. No accounts, no downloads, no "can you share your screen?"
Code that actually runs. Run code in a secure sandbox and see the output right away: stdout, stderr, and exit codes. It works with 20+ languages like TypeScript, Python, Go, Rust, Java, and C++. Multi-file projects work too, and you get live browser previews for React, Vue, and Svelte.
Screening that grades itself. Build a coding test once and send candidates a link. Results come back scored automatically. Pull questions from a shared library, make the hard ones worth more, and get one clear score per candidate. No rubrics to argue over.
See how they think. Replay every keystroke to see how a candidate got to their answer, not just where they ended up. AI is part of real work now, so you can also watch how they prompt and iterate with the built-in assistant.
Make it yours. Add your logo and colors, then track your hiring metrics to see where things slow down.
Self-hosting
CoderScreen is fully open source and self-hostable on Cloudflare. Grab the code and follow the Quick Start guide to get an instance running locally or in production.
git clone https://github.com/CoderScreen/coderscreen.git
cd coderscreen
pnpm install
Self-hosting is something we're actively polishing, so if you hit a snag, come say hi in Discord — we're happy to help you get unstuck.
Tech stack
CoderScreen is a pnpm monorepo built with React, TypeScript, Cloudflare Workers, PostgreSQL, Drizzle ORM, and TailwindCSS.
Apps
Packages
| Package | What it is |
|---|
ui | Shared React component library. |
db | Shared Drizzle ORM schema and client. |
email | Shared email templates. |
common | Shared utilities and types. |
scripts | Operational and maintenance scripts. |
Contributing
We'd genuinely love your help — bug fixes, new features, better docs, or just telling us where things are confusing.
- Fork the repo and branch off
main.
- Follow the Quick Start guide to get set up.
- Open a pull request and tell us what you changed and why.
Got an idea or a question first? Start a discussion or drop into our Discord. And if the project is useful to you, a ⭐ goes a long way.
License
CoderScreen is licensed under the GNU General Public License v3.0.
