Write some Software

Hello! I am using a Linksys E3000 WiFi router at home with the "Tomato v1.28 by Shibby" firmware installed (alternative Linux-based firmware). I need help to create a script to run on this router to synchronize folders (a folder in the USB Disk attached to the router and a folder over the internet -OneDrive from Microsoft, UNC-). This script will be scheduled to be executed every 30min (function already available in the firmware). I believe that some specific synchronization tool should be also installed first on the router, such as "Free File Sync" (no idea if it is possible, and no idea about how do it). The goal is avoid to use an another device (PC, ..) to do it when connected to the network, if the router can do it "online".