503 Backend fetch failed errors

Hi,

I’m getting a lot of these errors with coypu (several per day), but not systematically.
Is this a problem on my end, or is this on the sever end ?

Query for: stage=OK&animal=coypu&ts=1541573277
Target: https://buildfarm.postgresql.org/cgi-bin/pgstatus.pl/53b137e7c765b781699bbe73e3aec7751a8c4ab7
Status Line: 503 Backend fetch failed
Web txn failed with status: 1
Query for: stage=OK&animal=coypu&ts=1541575423
Target: https://buildfarm.postgresql.org/cgi-bin/pgstatus.pl/5e8e0913dc9f9a580a4125264d74fff95f26c926
Status Line: 503 Backend fetch failed
Web txn failed with status: 1

Regards,

Rémi Zara