After many hours and a grand total of 3 beers, I’ve managed to figure out the problem. After hours of digging, I finally came across this Server Fault answer
In layman terms, it appears that programs that create files in /tmp
(or /var/tmp
as I have discovered) are the only programs that are able to see the files in that directory. Unicorn was creating the UNIX socket file, however Nginx could not see it.
The solution I have employed is to have Unicorn create sockets in /var/sockets
.