ISTM parameter would be better named (i.e., mentally remembered as) "default_maximum_pool_size" ... and a zero for that seems like you'll render your system inoperable since:
"Notice that I don't set a pool_size for every database, but instead I use
the general default_pool_size.
> *My goal is to find a pgbouncer configuration that allows me to add
> databases without worring about reaching the postgresql max_connection=200
> limit. How can I achieve that?*
The presence of open issue # 103 on GitHub implies that what you want to do is not possible.
