I haven’t been able to find one and I think it’s important.
Seeing how the UI, Backend, databases, and the fedeverse interact with each other can really help developers see the big picture. It can help remove barriers to entry, give people an idea on where to start for contributions.
If there isn’t one let’s create one. Who ever knows the flow and architecture of this app, please drop a line in the comments.
Well as dumb as it sounds, I’d say it’s probably best to just read the code that you’re interested in (I was never a big friend of schematic overviews anyway, they’re often not in sync). Otherwise something like this is always a starter for newcomers: https://github.com/LemmyNet/lemmy/issues?q=is%3Aopen+is%3Aissue+label%3A"extra%3A+good+first+issue"