I'm sure you all are as tired of the occasional spam that hits
these lists as I was deleting it. (Mailing list users in
particular, I guess, since we can't delete an email once it was
sent out.) Most of the spam was coming in through the forum, so I
suppose I was responsible for [not] keeping it out.
Although forum.dlang.org has had a spam check and used reCAPTCHA
since it was announced, it is only somewhat effective against
fully-automated bots - it is powerless against humans paid to
post spamverts on forums web-wide, which is what the current spam
economy seems to be gravitating towards.
Enter DCaptcha, a question-answer challenge tailored for D
programmers. Its goals are to challenge posters of
suspicious-looking content with questions that should be easy to
answer to D programmers, and impossible for non-technical people
with no incentive to learn or research stuff (i.e. spammers).
DCaptcha is already in use on the D wiki (wiki.dlang.org), with
great success - DCaptcha's debut cut the short-lived explosion in
wiki spam to zero.
For an idea of what sort of questions DCaptcha asks, you can demo
it on the following page, so you don't have to clutter the forum
with test posts:
Pull requests for more challenges are welcome. You can find some
goals for new challenges at the top of dcaptcha.d.
Previous discussion (w.r.t. the D wiki):