Encrypting files

Hi, I am looking for an option to encrypt some files, more specific my backup files which I want to upload to Dropbox.
My Nextcloud is running on Ubuntu Server 18.04, which has no GUI.
I tried to install Cryptomator, but was not able to run it.

Does anyone know another application? Or can anyone help me installing and running Cryptomator?

Best regards,
Guido

You may have a look at restic and rclone.
restic is a backup program. And rclone can write to Dropbox.
Use the forums search function to find a post with anexample script.

Thanks for replying.
Writing to Dropbox is not a problem, first problem is encrypting.
I’ll have a look at restic and rclone.

Best regards,
Guido

restic will do encrypted backup.