The solution we saw previously can be implemented quickly, but there is a major flaw; reCAPTCHA is very well known, and there are various online services that offer to decode thousands of them for a few dollars (they can use Optical Character Recognition or even actual human solvers). In fact, any well-known system has the same problem, so sometimes the best solution lies more in the originality of the system than its absolute robustness. Indeed, even if the new system is much simpler, it will force spammers to specifically create new bots if they want to pollute your website, thus creating a kind of resistance (as long as your website is not popular).

We will therefore build a new CAPTCHA package in order to create our own original solution. Instead of displaying an image containing distorted text, we will simply ask the visitor to calculate a simple addition.