It isn't well documented and only tested on a SQL connection but it's just a set of wrappers around Racket's DB drivers, so you could try including that into your app.
Unfortunately I seem to have completely lost my test project but the connection should work as follows:
(= dbconn (postgresql-connect user db password))
btw I caught a misspelled 'password' in postgresql-secure-connect:
(mac postgresql-secure-connect (user db ssl-protocol (o passowrd nil))
oops. It's fixed, thanks.
(= dbconn (postgresql-connect "root" "root" password))
(table-exists? dbconn "items")