I keep my Obsidian notebooks and several source code repos in syncthing and then have them auto-shared between all my computers and my phone. Its been a great system, all my docs I need are readily available on all my devices with almost no delay and no cloud needed. A little advanced configuration to allow local deletes and I also have all my phone photos backed up this way too.
When I travel, I use my laptop and phone on a little travel router, so they’re always networked together and syncing files. Definitely saved my butt a few times!