* [ALTCHA v3.3.0](https://github.com/altcha-org/altcha) – Self-hosted privacy-first security solution protecting websites and APIs from spam using a proof-of-work mechanism.

* [FCaptcha v1.44.0](https://github.com/WebDecoy/FCaptcha) – Detect bots, vision-based AI agents, headless browsers and automation using 40+ behavioral signals plus server-verified SHA-256 proof-of-work.

* [Private Captcha v1.45.0](https://github.com/PrivateCaptcha/PrivateCaptcha) – Independent, privacy-first, self-hostable Proof-of-Work CAPTCHA service built in the EU.

* [ALTCHA JS Library v2.6.0](https://github.com/altcha-org/altcha-lib) – Lightweight, zero-dependency JavaScript library for creating and verifying ALTCHA challenges.

* [ALTCHA Go Library v2.4.0](https://github.com/altcha-org/altcha-lib-go) – A Go library for creating and verifying ALTCHA v2 proof-of-work challenges, including local and remote verification support.

* [Scrapfly Anti-bot Detector v2.8.5](https://github.com/scrapfly/Antibot-Detector) – Manifest V3 Chrome extension detecting CAPTCHAs, anti-bot systems, and browser fingerprinting in real time with confidence scores and capture tools.

* [React Turnstile @marsidev/react-turn...](https://github.com/marsidev/react-turnstile) – Cloudflare Turnstile integration for React applications offering automatic script injection, SSR readiness, and TypeScript support.

* [Cap standalone@3.1.13](https://github.com/tiagozip/cap) – Lightweight, modern CAPTCHA alternative using SHA-256 proof-of-work focused on privacy and ease of integration.