If you need to store files on a CDN such as Amazon S3, or other SFTP/FTP capable location in ExpressionEngine 3, Treasury is the solution you need!
Treasury makes setting up your file locations easy. Use any Amazon S3 bucket, use private key authentication for SFTP — whether it’s a key on your server, or a specific key to your location, or use standard FTP.
And if you need to combine Treasury’s file storage engine with the power of Ansel, you can do that too! Ansel is fully compatible with Treasury. In fact, with the Treasury API, any developer can make their applicable add-on Treasury aware.