FreeBSD users should be able to install this via pkg install pooler
It was committed to FreeBSD's ports tree
under /usr/ports/biology/pooler, porting discussion was on issue 251065,
v1.77 update was 472c25a
discussed at 257975,
v1.78 update was 541454f
discussed at 258120,
v1.82 update was 8d34513
discussed at 261741,
v1.84 update was 3b861fa
discussed at 262498,
1.85 update was bcc206f
discussed at 265163,
1.86 update was a75fab4
discussed at 268445
(this core-dumped on a quarterly build 8 months later along with 60+ other packages possibly due to an infrastructure problem, but pkg install still works at least on 64-bit),
1.88 update was 8abd028
discussed at 273604,
and
1.89 update was 70c1cdc
discussed at 284463