The engine has a machine
Unreal Engine 5.8 is built from source on a dedicated Windows host, with a cross-compiler the engine itself agrees can produce Linux servers.
Zizeeria's dedicated server runs on Linux and the engine is built on Windows, which means a cross-compiler and a matching toolchain pinned to the exact version the engine expects. That combination was verified before anything was built on top of it: a program compiled on the Windows host, sent to a Linux machine, and run there. Discovering a broken cross-compiler after a two-hour build is the expensive order to discover it in.
The engine now lives on its own host rather than on a workstation — a hundred and nineteen gigabytes of it, before anything is cooked. Three of the four things that went wrong getting there were the same shape: a step that reported success and did nothing. An installer that returned zero having installed nothing, because an earlier flag had quietly removed the file it needed to know what to install. A build launched over a remote session that vanished when the session closed, leaving a log that stops mid-sentence and looks exactly like a build still running.
The fourth was better: the setup script hangs for ever on a machine with nobody at the keyboard, because its last step opens a dialog box asking whether to register the installation. Nothing in the log says so. The way to find it is to count the processes rather than read the log, which is now written down where the next person will look.