1. build a #docker image from https://github.com/mozilla-services/syncserver
2. #deploy it somewhere
3. configure identity.sync.tokenserver.uri in #about:config to point to your new location
4. login at `about:preferences#sync` (you still need a #mozilla account, unless you also run a private account server)
5. sync and check about:sync-log for #error|s
@martin it uses your Firefox account, so yeah, it syncs with both FF & Epiphany. E. g. when sharing a link via Firefox mobile I can send it to Firefox desktop, or Epiphany.
mstdn.binfalse.de is one server in the network