We are co-organizing the seventeenth year of the Prague PostgreSQL Developers Day (P2D2) conference. The two-day event will offer workshops and lectures on PostgreSQL, the relational and open-source database system. Among the invited speakers are members of the core team of this database. This year we are expecting twice as many lectures in two parallel sessions. We're also adding a 3rd line of workshops scaled to work directly with the PosgreSQL core in C. The event is paid, and registration is required.