Same! Set up a DIY home battery system and needed something to communicate with the inverter and battery over RS232, RS485 and bluetooth. Had an old Raspberry Pi-B with 512MB RAM lying around.

Running 3 python scripts as daemons would become a tad heavy and was a bit worried about serial timing. So used Codex to rewrite them in Go. Cross-compiled them, deployed the binaries and they're now running very comfortably on the pi. A few MB of ram per daemon. Making good use of an almost 15 year old device.