@spamty Think of some simple puzzles yourself, and write a small program to implement them.
Throw together a few puzzles like that. Have a visual, audio and text.
@spamty It doesn't need to be fancy, because it's only on your site (and perhaps a few others). This will protect you against non-targeted attackers, which is all you really need; a targetted attacker would just pay hCaptcha for some hCaptcha bypass tokens.
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