Unless I am blind or my search-fu is hugely failing me, I cannot for the life of me find any information on the recommended/minimum specs to self-host the matrix backend services. I’m trying to spin up a VM just to play around with it and see if I like it. Specifically, I’m looking at Synapse or Continuwuity. Any advice?
Looking for vCPUs, memory, storage.
As others have already alluded to, Matrix is a bit odd in that regard as it runs a distributed database and the resource requirements depend on how much of the matrix network is mirrored on it. A single power-user can cause huge resource use just by connecting to a lot of federated active rooms. On the other hand a server that is mostly used as a private family chat can run on a modern RasberryPI without much problems.
Synapse or Conduwinity etc. makes little difference in praxis as both need to do the same database merging operations.
I do appreciate that, but even a starting point would be nice.
Starting point based on what? Do you plan to use it personally to join many large channels from FOSS projects? If so, you need to plan for a relativrly beefy VPS, like 4 core, 8gb ram, 100gb+ ssd storage.
But for small private chats with no federation a cheap minimum VPS can work.
If you want my personal recommendation I would avoid hosting Matrix. A well federated server is costly to run and not really worth the hassle and a small private chat server with bridges etc can be done equally well or better with XMPP.
I did not ask for a recommendation of if I should use or not use Matrix. I stated in OP that I want to play around with it. I will decide if it’s right for my use-case.