I can easily run Pleroma on 1G VPS and Pi3s; the heaviest part is the Postgres server, which can itself be tuned to be pretty light. It relies on PG's native JSON data type which is cool. I run a couple instances and poked around with it for a few hours. I'd love to see SQLite support in Pleroma given that it allegedly has JSON now; there is a 2 year old ticket on their GitLab [1] mentioning it tho I've not spiked in to see if it's 100% plausible to port. Pleroma is written with Elixir that has a DB abstraction library that supports SQLite, I was just looking into it this week.
Even if SQLite JSON isn't sufficient it could be realized with string columns for now, and indeed SQLite is recommended by Library of Congress for archival storage and used by iPhone so I think it's a solid way to expand Pleroma even if native JSON is not sufficient.
If anyone wants to pay me to do this as open source I'd jump, contact in bio. I don't know Elixir yet but am motivated and have 15+ years of dev experience in all kinds of systems, and experience in the adjacent parts.
It's a ruby application. Take all the background processes to build timelines, trending hashtags, etc and it adds up. Perhaps a single-user instance might do with less, but still...
