Ron,

Thanks your interest in this. I'm curious about the decision to move the imaging code into the core. Uploading could be about a lot of other transformations besides image resizing, and the old design of handing image transformations through a helper module seemed like a reasonable interface:

Before:

gen_files => {       
   'my_thumb' => gen_thumb({ w => 100, h => 100 }),
 }
[download]

After:

 transform => {
    imager  => Imager -> new(),
    options => {xpixels => 400, ypixels => 500},
}
[download]

That looks worse to me, and sets a precedent for supporting imagers internally, while before there was example of adding new transformers via plugins.