This is a Captcha gem for Rails Applications. It drawing captcha image with C code so it no dependencies.

ActsAsTextcaptcha provides spam protection for Rails models with text-based logic question captchas. Questions are fetched from Rob Tuley's textcaptcha.com They can be solved easily by humans but are tough for robots to crack.

Captcha-Plugin for Rails

Arithmetic Captcha

Unobtrusive, flexible and simple spam protection for Rails applications using honeypot strategy for better user experience.

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reCAPTCHA was too much for us, so we created this. Simplest captcha ever.

Quick little arithmetic plain-text captcha

Rack middleware Captcha verification using Recaptcha API.

DeathByCaptcha allows you to solve captchas with manual labor

Despamilator is a plugin based spam detector designed for use on your web forms borne out of two annoyances: Spam being submitted in my web forms and CAPTCHAS being intrusive. Despamilator will apply some commonly used heuristics from the world of anti-spam to help you decide whether your users a...

Captcha generator for rails

dongsx

Drop in feedback engine with customizable fields, and captcha available

这是一个验证码生成器。基于rucaptcha。本人只是将他的源码拉下来。为我的网站进行适配。因为我不使用sesion.id

SimpleCaptcha is available to be used with Rails 3 + 4 or above and also it provides the backward compatibility with previous versions of Rails.

A library to make creating negative captchas less painful

Ruby wrapper for Yandex.Cleanweb

It's a Rails Captcha Engine for Rails 3 applications.

A Google-style captcha for enterprise Rails apps