Original fire processing?

Hello everyone! first post! I have been using Shrine for the past few months, and after getting acquainted with it, I love it! There is just one thing that has been giving me trouble so far:

What is the right way to process an uploaded file, on promoting to store from cache, and save it not as a variant, but as the original file itself?

The documentation is clear and extensive about variants, I have no problem with them, but my specific use case is about compressing pictures and videos to save storage space, so I don’t want to store an original file and a variant, just a compressed version of the original file.

I came across a processing plugin when searching the documentation, and I thought it would be, but it didn’t appear to work with async promoting jobs, and it also gave me a deprecation warning and told me to use the variants plugin, which again, doesn’t fit my use case.

So… is there a right way to do this? Is it documented and I missed it? It’s not supported?