Really sounds like an awesome tool. Fits right into the serverless / JAMStack kind of systems too. Just like Netlify CMS.

I was actually in the process of tweaking Netlify CMS to be more easily hostable yourself without depending on the Netlify Pro plans as much. Basically involves hosting a combination of Netlify Identity and Git Gateway compliant backends in GCP CloudRun or AWS Lambda. Maybe even making it easy to configure a build pipeline on CloudBuild.

I wanted to use this for small business websites, but also configuration management and translations for projects at work. Sounds like FlyCode is a great (not self-built) alternative I can recommend. Great business model as well. Almost no databases needed (auth only?) and easy to host stateless on serverless offerings. Scales linearly