To further expand on alfie - PostgreSQL's connection limit can be upped arbitrarily but that's limited by the amount operating system's shared memory. When I install PostgreSQL on OpenBSD I have to make a tweak to the kernel to up the maximum limit. This is all documented so it's nothing to worry about but it would be misleading to simply look at PostgreSQL's arbitrary 32 connection limit and ignore the OS's less but still arbitrary limit.

__SIG__
printf "You are here %08x\n", unpack "L!", unpack "P4", pack
  "L!", B::svref_2object(sub{})->OUTSIDE;
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