GoodSync - GoodSync provides highly reliable file backup and synchronization for both individuals and businesses.
ifttt - IFTTT puts the internet to work for you. Create simple connections between the products you use every day.
rsync - rsync is a file transfer program for Unix systems. rsync uses the "rsync algorithm" which provides a very fast method for bringing remote files into sync.
Zapier - Connect the apps you use everyday to automate your work and be more productive. 1000+ apps and easy integrations - get started in minutes.
Syncthing - Syncthing replaces proprietary sync and cloud services with something open, trustworthy and...
n8n.io - Free and open fair-code licensed node based Workflow Automation Tool. Easily automate tasks across different services.