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Kate
Kate

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A zero-telemetry, gamified CAPTCHA for React

Hi HN,

We built conversion.business, a drop-in replacement for traditional captchas (like reCAPTCHA and hCaptcha) that uses 2 - 5 -second HTML5 micro-games instead of traffic lights and blurry crosswalks.

Why we built this: We were frustrated by the amount of friction traditional captchas introduce to sign-up flows. More importantly, we disliked the privacy implications of modern captchas that require extensive background telemetry, behavioral tracking, and cross-site cookies just to prove humanity.

How it works technically: We wanted to prove humanity without tracking the human.

Zero Telemetry: The widget uses zero cross-site tracking cookies and zero local storage. We don't track mouse curves or micro-interactions.
Game Randomization: We serve unpredictable, multi-game challenge rotations on every page load to prevent attackers from training targeted machine-learning bots for a single puzzle type.
Verification: The widget measures total solve time, checks WebGL renderer signatures to block headless browsers/software renderers (like SwiftShader or llvmpipe), and validates User-Agents.
Cryptographic Seal: When a game is solved, the payload is verified on our backend, and we return an HMAC SHA-256 signature keyed to your server’s secret. You verify this signature before accepting the form submission.
Accessibility: It is 100% ADA/WCAG 2.1 AA compliant. There is a strictly rate-limited, keyboard-navigable accessibility bypass for screen readers.
We just released our official React NPM package (react-gamified-captcha) which compiles to standard ESModules/CommonJS and is fully SSR-safe for Next.js.

We know developers are rightly skeptical of third-party widgets, so we set up a live CodeSandbox where you can see exactly how much code it takes to implement and play the games right in the browser: https://codesandbox.io/s/github/oops-games-llc/conversionhub-integration-examples/tree/main/sandbox-template

I'd love to hear your feedback on the architecture, the game mechanics, or any edge cases we might have missed!

Top comments (1)

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mehrdoost profile image
Mdm

Interesting approach. From a pentesting perspective, the WebGL renderer check is clever but not airtight — headless browsers can now spoof GPU profiles or use software rendering that mimics real hardware. Bot operators also commonly use anti-detect browsers that expose exactly the fingerprint you're checking. The real strength here is the combination of short-lived game randomization plus the HMAC signature; that raises the cost for attackers who just replay solutions or train a generic solver.

One thing I'd keep an eye on: the accessibility bypass, even with rate limiting, often becomes the path of least resistance in automated attacks. I've seen audio challenges abused this way. If the rate limit is per-IP, residential proxy pools chew through it fast. Might be worth binding it to a server-side session token rather than solely IP. Are you planning to open-source the verification side or keep it SaaS-only? That transparency would help with trust.