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Jaco
Jaco

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Why I stopped using CAPTCHAs and built a behavioral API instead

#webdev #api #security #showdev

The breaking point

A form we ran had a CAPTCHA. Completion rate: 58%. After removing it: 81%. Bots barely slowed down. Real users just left.

That's when I realized: CAPTCHAs aren't really protecting you. They're taxing your real users to slow down bots by seconds.

The insight behind HUMA

Humans and bots behave fundamentally differently.

When a human fills out a form, they:

  • Move the mouse in curved, organic paths
  • Type with natural rhythm — faster on familiar words, pauses before corrections
  • Scroll unevenly, sometimes going back up to re-read
  • Take time to think before clicking

Bots execute scripts:

  • Linear mouse paths or no mouse movement at all
  • Perfectly timed keystrokes
  • Instant form completions
  • Zero hesitation

These behavioral signals are a much richer signal than "can you read this blurry text."

How HUMA works 

<!-- 1. Drop this on your frontend -->
<script src="https://humaverify.com/huma.js"></script>
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# 2. Call this from your backend
curl -X POST https://humaverify.com/api/v1/verify \
  -H "Authorization: Bearer huma_live_..." \
  -H "Content-Type: application/json" \
  -d '{"userId": "user_123"}'
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{
  "human": true,
  "confidence": 0.94,
  "token": "h_verified_Kd3mP8luYMC2Mi1x",
  "pii_stored": false
}
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No UI shown to the user. No friction. No personal data stored.

Node.js SDK 

npm install @usehuma/node
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import Huma from "@usehuma/node";
const huma = new Huma("huma_live_your_key");
const result = await huma.verify("user_123");

if (result.human && result.confidence > 0.7) {
  // ✅ Real human — let them through
}
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Try it yourself

You can run the demo at humaverify.com/demo — no account needed. It takes ~6 seconds to collect signals and shows you your own confidence score.

I'm Jaime, I built this solo in Mexico City. Launching today on Product Hunt — would love to hear your thoughts, especially from devs who've dealt with bot abuse on their own products.

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