Say hello.
No support tickets. No chatbots. Just a real inbox, read by a real person.
What to expect
Fast reply
Usually within 24–48 hours. No ticket queue, no auto-responders.
Human on the other end
You'll be talking to the person who actually wrote the code.
Your email stays private
Never shared, never sold. Consistent with everything Captxa stands for.
About this project
"Handcrafted in Barcelona by an independent computer science student. Built resilient — like the Catalan Donkey."
Captxa is a solo project. There is no VC money, no growth team, no tracking dashboard silently profiling your users. It started from a simple frustration: every CAPTCHA solution available either spies on your visitors, bloats your page, or degrades the experience for real humans.
So I built one from scratch — in C, on H2O, with a clear head and a stubborn commitment to doing it right. The Proof-of-Work engine, the sliding puzzle, the ML trajectory analysis — all written by hand, one line at a time, from a flat in Barcelona.
Privacy is not a feature here. It is the architecture. No cookies beyond what's strictly necessary, no third-party calls, no IP-based blocking, Ed25519-signed tokens you can verify yourself. If you care about your users' data, Captxa was built for you.
Built with
- C — low-level, fast, honest
- H2O HTTP/2 server
- ChaCha20-Poly1305 encryption
- Ed25519 token signing
Principles
- Zero non-essential cookies
- No IP-based blocking
- Fully auditable, no black boxes
- GDPR compliant by design
Public client script
The browser-side JS is open for inspection. No surprises. github.com/HelloCaptxa/PublicJS
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