Thank you. Shame on me, that I have forgot about it. Actually I have even uploaded one of my extension (IMCS) to PGXN.
May be I am wrong, but it seems to me that not so much people know about pgxn.org Before writing this mail I have tried to locate such resource in Google and didn't succeed.
yes, It is not strongly joined with the Postgres community, and it doesn't deploy binary (compiled) code if I know it. So for some people it is not usable.
But anytime this and similar repositories will have problems, because the extensions there are not reviewed, nobody did security check, nobody did QA.
This is useful for Postgres developers, for very advanced users, or for very fearless users :).