Hiya! I'd seen this API when it was first released, and while I've never had a use for it, I did have a similar use case with a recent update for Crushing Industry. I needed support for quality and multiple spoil results from the same item (i.e. 1 concrete mix barrel spoils into 5 concrete by default), so I copied your implementation and modified it to support my needs.

So thank you for showing it was possible!

Also if you add support for those needs I'd be happy to use this mod as a compatibility instead, though the quantity thing may be a more unique use case for my mod lol. Regardless, credit is given on the mod's page and in the CREDITS.md distributed.

EDIT: Link to code

Hey! Thanks for liking my mod and the credit :)

There's another mod that allows quality and works way better if you need something more advanced and I used it for one of my mods.

I'll see if I can add quality and more than one item to this though.

The mod is https://mods.factorio.com/mod/runtime-spoilage-library so if you want to use that you can.

Here is a link to the docs of the runtime-spoilage-library mod: https://github.com/SirPuck/runtime-spoilage-library?tab=readme-ov-file#limitations-read-this-please-like-really-this-is-important

I have updated the mod to provide these new features :)