cap — modern, lightning-quick PoW captcha

Cap is a lightweight, modern open-source CAPTCHA alternative designed using SHA-256 PoW.

• ⚡️ 250x smaller than hCaptcha
  Cap's widget library is extremely small, only 12kb minified and brotli'd.
• 🔒️ Private
  Cap's usage of proof-of-work eliminates the need for any tracking, fingerprinting or data collection.
• 🌈 Fully customizable
  Cap is self-hostable so you can customize both the backend & frontend — or you can just use CSS variables
• 🤖 PoW-based
  Cap uses proof-of-work instead of complex puzzles, making it easier for humans and harder for bots
• 🧩 Standalone mode
  Cap offers a standalone mode with Docker, allowing you to use it with languages other than JS.
• 💨 Invisible mode
  Cap can run invisibly in the background using a simple JS API.
• ☁️ Floating mode
  Floating mode keeps your CAPTCHA hidden until it's needed
• 🌳 Fully FOSS
  Completely open source under AGPL-3.0, with no premium versions.