[vosper]

It's surprising to me that on-prem reCAPTCHA isn't a service that seems to exist (based on a quick search).

Even if it's not Google's reCAPTCHA - is it so hard to make something like this that only Google can provide it? Surely the big players would want this component under their control exactly for reasons like "we don't want to have an outage due to a provider outage". Or at least, fail over to a less-preferred backup. Like if Cloudflare had such a service.

[fragmede]

Cloudflare looked at the options (including building their own) and moved to hcaptcha (but mostly because Google wanted to charge them money), so it must be hard at that kind of scale, since bot writers are monetarily incentivized to defeat the captcha.

https://blog.cloudflare.com/moving-from-recaptcha-to-hcaptch...