[aabbcc1241]

I usually take YAGNI further and avoid using database (sql or nosql) at all (at least in the beginning)

My typical approach is to log all the commands to the file(s), and keep the system state in memory. When the server restarts, it simply replay most of the commands (skipping those intended to cause side effect)

This is like simplified event sourcing, or command sourcing.

I'm not relaying on any framework to build the backend, simple library handing rest and websocket API is enough.

I'll open source it soon but it's mostly as simple as it sounds, with some optimization to reduce disk space consumption after they becomes a problem in practice.