No need for an Ansible vs. Docker argument when you can combine them both!
I run a similar project called Ansible-NAS - https://github.com/davestephens/ansible-nas - which originally came about because I fell out of love with FreeNAS, and felt I could do a better job with Ubuntu, Ansible, and a bunch of Docker images.
Sovereign is awesome, I've been watching it for a while, but I'm not keen on everything being installed directly onto the system which is what I tried to solve with Ansible-NAS.
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