@kurt AH! FOUND THIS AND GOT IT WORKING!
Thank you for your help! Now that I’ve got this figured out, I feel like it’ll be MUCH easier than dealing with DigitalOcean’s S3 API. Love being able to save uploads with normal file read/write commands instead of needing to setup and use a bunch of extra S3 libraries. This is a really nice feature.
I just ended up running chown on the volume via fly ssh console. Just to check, though: is there any reason that ownership assignment might get reassigned back to root on a future deploy, or should that permission setting be more or less permanent at this point? Just want to make sure there isn’t a risk of the permissions issue unexpectedly returning in the future.