Fulfillment is really complex. I work for Fangamer, who is shipping the Double Fine Adventure posters and shirts. We built out our own tech to get postage print

Fulfillment is really complex. I work for Fangamer, who is shipping the Double Fine Adventure posters and shirts. We built out our own tech to get postage printed (and confirmation emails, accounting handled, etc.) to be able to ship everything. It's been a project to ship ~13k items.