As a solo founder, your time is the most precious resource so all your DevOps effort should be minimized to the extent that you can prevent and debug issues. In practice, for me, this meant using tools that I'm already comfortable with (preferably in the same language as my codebase to minimize context switching) and resisting making things overly complicated with too many tools in the chain. For automated deployment, I'm using Fabric (for Python) that allows me to remotely run commands. DB backups are handled by cloud snapshots and rollbacks are ad-hoc based on Git.

This was also how things began at a previous startup I worked at until we grew and we could hire more resources to fix things.