It's good to see Balena getting some attention - it's a really nice way of deploying containerised software to embedded devices, and managing them in the field. I've been using the free tier for managing a couple of rpis I have round the house in a reproducible way.
It's basically a whole platform built around docker-compose, so you write a compose file for your different applications and then can deploy it to any embedded Linux computer running the Balena OS. Balena manage all the complicated stuff around rolling out updates, keeping the OS up to date, logging etc, and give some nice debug tooling. The other nice thing about the platform is that it's almost all open source - so if Balena the organisation goes bust or changes strategy, Balena the IoT management service could be self hosted.