There is a company in Russia called Postgres Pro https://postgrespro.ru/ and they are those people who added json functionality to postgres. As far as I know they work on full text search for postgres now.

There's a bunch of stuff scattered around on mailing lists and conferences: I think it's the main data source for Yandex's email offering (gmail equivalent). They've got an async C++ library for postgres called Ozo, and they're quite active in the community!