I'm curious why the FastLED library can target a Gemma,

I’m curious why the FastLED library can target a Gemma, but not a bare ATTiny85 running the Arduino bootloader. What capabilities could the Gemma have that the ATTiny doesn’t?

Compilation fails when I build for ATTiny. Sorry, I don’t have the error message on hand.

For me, mostly it’s about time. I have a Gemma and a trinket that I can use for testing with, and so that is what I limit official support for - if someone wants to run with a bare attiny85 go for it, I believe there are some folks who have.

(With supporting nearly a dozen different Avr board/configurations and another half dozen distinct arm architectures, I need to pick and choose what I directly put time into)

Understood!

That said - when you get to a point of trying building again, drop the error message(s) ours getting here and I can probably tell you what’s up/needs to be tweaked.