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ALTCHA

ALTCHA

Self-hosted, privacy-friendly CAPTCHA alternative with proof-of-work mechanism

ALTCHA preview

ALTCHA is a GDPR, WCAG 2.2 AA, and EAA compliant CAPTCHA alternative that protects websites from spam and abuse without compromising user privacy. Unlike traditional CAPTCHAs, ALTCHA uses a proof-of-work (PoW) mechanism to verify human interaction, ensuring accessibility and privacy compliance.

Key Features

  • Privacy-Friendly: No tracking, cookies, or personal data collection, fully compliant with GDPR, WCAG 2.2 AA, and EAA.
  • Self-Hosted: Complete control over deployment and data, with no reliance on third-party services.
  • Proof-of-Work (PoW): Uses computational challenges to distinguish humans from bots without invasive checks.
  • Accessible: Designed to be inclusive, supporting users with disabilities and screen readers.
  • Lightweight & Fast: Minimal client-side footprint with efficient server-side verification.
  • Customizable: Supports theming, custom challenges, and integration with various frameworks.
  • Open Source: Free to use, modify, and distribute under the MIT license.

Tech / Self-Hosting

ALTCHA is built with modern web standards and can be self-hosted on any server or platform. It supports:

  • Frontend Integration: Works with vanilla JavaScript, React, Vue, Svelte, and other frameworks.
  • Backend Verification: Compatible with Node.js, PHP, Python, Go, and more.
  • Docker Support: Easy deployment using Docker containers for scalable setups.
  • No External Dependencies: Operates independently without requiring third-party APIs or services.
Tech Stack & Architecture12 technologies detected