Recommendations for PGBouncer interacting with HikariCP

Hi pgsql-jdbc email distribution list,

We have recently added PGBouncer into our stack. We have done this in part,
to protect the database. Our Java userbase is accustomed to using HikariCP
/ Hibernate for connection pooling. They would prefer to continue to use
the connection pooler, in order to not have GC churn on connection spin up
and tear down (in addition to additional latency introduced by having to
perform the three-way handshake more often).

Is there any published material / does anyone have any knowledge of how
these tools should interact or not interact? HikariCP wants to keep many
long running idle_in_transaction connections open, which saturates the
backend connection pool.

Thanks in advance for any assistance anyone can provide,
Joe