tiago
50 lines
2.9 KiB
Markdown
50 lines
2.9 KiB
Markdown
# <img src="https://github.com/tiagozip/cap/blob/main/docs/public/logo-small.webp?raw=true" alt="" align="left" width="40" height="40"> Cap
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Cap is a lightweight, modern open-source CAPTCHA alternative using <a href="https://capjs.js.org/guide/effectiveness.html">SHA-256 proof-of-work</a>. It's fast, private, and extremely simple to integrate.
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<a href="https://capjs.js.org/guide/demo.html"><img src="./assets/captcha.svg" alt="Cap widget" width="250"></a>
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## Documentation
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[Read the Cap docs](https://capjs.js.org), try the [demo](https://capjs.js.org/guide/demo.html) or read the [feature comparison](https://capjs.js.org/guide/alternatives.html)
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## What is Cap?
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Cap is the modern, open-source alternative to traditional CAPTCHAs that uses proof-of-work instead of annoying visual puzzles.
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It's built with JavaScript and Rust and has no dependencies. You can either run it on any JavaScript runtime (Bun, Node.js, Deno), or use the standalone mode with Docker.
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Cap is built into 2 main parts. The [widget](https://capjs.js.org/guide/widget.html) is a small client-side JavaScript library using custom components and WASM that renders the CAPTCHA and solves the challenge.
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The [Standalone Server](https://capjs.js.org/guide/standalone.html) is a Docker image that helps you use Cap with any language or framework. As an alternative, if your server-side uses JavaScript, you can use the lighter [server](https://capjs.js.org/guide/server.html) library.
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Cap also has a [M2M library](https://capjs.js.org/guide/solver.html) that implements a custom proof-of-work solver for protecting API endpoints that you still want public.
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## Why Cap?
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- **250x smaller than hCaptcha**
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~20kb, zero dependencies, loads in milliseconds
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- **Privacy-first**
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Cap doesn't send any telemetry back to our servers
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- **Fully customizable**
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Change the colors, size, position, icons and more with CSS variables
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- **Proof-of-work**
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Your users no longer have to waste time solving visual puzzles.
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- **Standalone mode**
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Run Cap anywhere with a Docker container with analytics & more
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- **Invisible**
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Hide Cap's widget and solve challenges in the background
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- **M2M**
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Keep your APIs protected while accessible to friendly robots
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- **Open-source**
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Completely free & open-source under the Apache 2.0 license
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Cap is a great alternative to [reCAPTCHA](https://www.google.com/recaptcha/about/), [hCaptcha](https://www.hcaptcha.com/) and [Cloudflare Turnstile](https://developers.cloudflare.com/turnstile/)
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## License
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Apache 2.0
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Copyright (c) 2025–present tiago
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[](https://www.bestpractices.dev/projects/9920) [](https://www.producthunt.com/posts/cap-5?embed=true&utm_source=badge-top-post-topic-badge&utm_medium=badge&utm_souce=badge-cap-5) |