My simplest "Arduino" circuit

Yes, I compiled the code with the IDE. I think you need to add this link to the Additional Board Manager URLs in the Preferences:

https://raw.githubusercontent.com/damellis/attiny/ide-1.6.x-boards-manager/package_damellis_attiny_index.json

Then under Tools -> Board -> Board Manager you find the entry for the Attiny group, select it, and click Install.