The only other thing I've seen in this space is DodgerCMS. It may meet your needs as it seems to do a lot more than Tumbless already. I think I prefer the way it handles credentials too(saved in local storage iirc rather than in a "hidden" file that's technically available to everyone)

https://github.com/ChrisZieba/dodgercms

Regardless, I think this is something that would be awesome to have. You can even throw in some AWS Lambda if you want to move some stuff out of the browser(like generating thumbnails/index pages/etc). Or just use Lambda to run a complete static site generator(like jekyll or pelican) every time the content in an S3 bucket changes.

Note: I've never actually used either of these, but I did spend a fair amount of time researching this type of stuff.

I read a lot about DodgerCMS right now, then I discovered it did client-site rendering. Not that this is a bad thing, but it makes the job of implementing a site like this so much easier that I got angry.

Now I don't know if Tumbless does everything client-side too. I guess the other way is way too hard (recompiling everything every time, finding what to recompile etc.), like I tried to do and failed with https://github.com/fiatjaf/coisas

Tumbless uses two passwords: the admin one could benefit from the local storage approach, however I'm not sure if chrome's password saving feature would help. The second one is the one you share with your guests if you choose to make the blog private. I see no other option here.

I'm not very happy either with the hidden file approach, as it might be vulnerable to brute force attack. Amazon does not specify what kind of protection they have in place. I definitely recommend hard to guess passwords.

You could look into adding a few lambda functions behind API gateway for functionality that you can't get natively from HTML5. It would be about the same difficulty of installation and have the same management profile (ie. upload and basically be done with it).

I guess one cold wrap a video transcoding engine into a lambda to keep traffic costs down.

Amazon actually provides a transcoding service too. :)

It's a wonderful time to create awesome side projects ;-)