How coupled is your code to your host? You should always design to lift-and-shift between these as easily as possible. That way you keep the benefits and aren't locked in.

Cloud functions products have been incredibly useful trade off for me. Whenever I want to process a lot of small files (read: tens or hundreds of thousands), I'll wrap some JavaScript into a function and it'll magically horizontally scale a function for a huge amount of tasks at the same time.

Has it done in seconds.