Show HN: A headless Synergy server setup for niche use cases

For someone with a bunch of retro machines that do not have a Synergy server port (and may not be near a machine that does or near one that I'd rather not run a Synergy server on) but do have a Synergy client port, using a headless Synergy server on a tiny SBC like the OrangePiZero makes for a slick, no frills setup to share a single mouse and keyboard among them.

How do I use this? I've currently got it connect across my Amiga 1000, Pegasos II running AmigaOS 4.1 FE and Pegasos II running MorphOS.

A bit more info For headless Synergy, we can't use xvfb (a virtual framebuffer) since it doesn't take input from physical devices. We can however use Xorg with a dummy device, which is similar to xvfb, but has the benefit of being able to use physical input devices. The below steps will go through the setup process and enabling a persistent Synergy server from the moment the system boots up.