>neat, however these custom captchas are still liable to just being knowledge checks
It's been agreed that the captcha questions for programming boards should resemble Leetcode/Project Euler/Advent of Code i.e. they will require programming, but be independent of any particular language. We'll have online compilers for 15 different languages, just like many other websites do, so getting a compiler at hand shouldn't be an issue. Of course, the problems are going to be much easier to do (they shouldn't take more than 10min to code for an experienced programmer) and won't be required for every single post to do  (because that would be ridiculous).

I agree with the poster above that knowledge checks aren't bad, although I also agree with you that filtering functional programmers just because they don't know OOP (or vice versa) is a bad idea. 

>Maybe something like a ravien matricies quiz to ensure that someone is big brained enough to post would be good.
Don't think an IQ test is a good captcha for any board except /iq/ and /ret/.

>I'd suggest liberating the source code to this captcha mechanism you have so users can contibute to it
I'll liberate some parts of the source code but not right now.