I work on a POS system at "a big software company" and a primary selling point is that your transactions flow up from the POS, to an optional in-store server, t

I work on a POS system at "a big software company" and a primary selling point is that your transactions flow up from the POS, to an optional in-store server, to the cloud, and if any point experiences a temporary failure (POS -> in-store or in-store -> cloud) it will simply batch-upload at the next opportunity, seamlessly, with no impact on the cashier's experience.