Build a Cloud Sync Engine that Supports Placeholder Files

I have sample code which can be seen at https://github.com/microsoft/windows-classic-samples/tree/main/Samples/CloudMirror The explanation of the code can be found at https://docs.microsoft.com/en-us/windows/win32/cfapi/build-a-cloud-file-sync-engine This code is written in C++... (Budget: $30 - $250 USD, Jobs: C# Programming, Windows Desktop)