Not really - these are designed specifically to be cross-body or fanny pack style - they only have 2 attachments for a strap where a backpack would require 4 attachments and 2 straps
I plan to do backpacks as my next project!
Sorry it took me so long to see this, I haven't figured out how to get to the updates and this page through my backerkit profile lol, so I use the emailed updates to get here! It's all good, I'm liking the idea of wearing my seagull and finch on my waist while I work, especially since I deal with wildlife! Just thought a backpack would be cute but I get it!