Even if it's just the build server, it's really hard to defend just having 1 physical server for a project that aspires to be a core part of the software distribution infrastructure for thousands of users.
The build server going down means that no one's app can be updated, even for critical security updates.
For something that important, they should aspire to 99.999% ("five nines of") reliability. With a single physical server, achieving five nines over a long period of time usually means that you were both lucky (no hardware failures other than redundant storage) and probably irresponsible (applied kernel updates infrequently - even if only on the hypervisor level).
Now... 2 servers in 2 different basements? That could achieve five nines ;)
The build server going down means that no one's app can be updated, even for critical security updates.
For something that important, they should aspire to 99.999% ("five nines of") reliability. With a single physical server, achieving five nines over a long period of time usually means that you were both lucky (no hardware failures other than redundant storage) and probably irresponsible (applied kernel updates infrequently - even if only on the hypervisor level).
Now... 2 servers in 2 different basements? That could achieve five nines ;)