https://byosynch.com/

Long time Dropbox customer. Really like its simplicity and convenience, but a couple things always bothered me: their lackluster command line support, and the fact that they have my files.

Byosynch tries to fix these gaps (first-class CLI support, backing store of your choice, privacy-friendly) while being easy to use.

We currently support macOS and Linux, with an iOS client coming soon.

This is a paid service, designed to finance continued development.

Happy to answer any questions and hear your feedback!