It's small grocery store chain in the middle of European nowhere, with about hundred of stores run mostly in small villages. Some of those ancient software was made in-house decades ago for internal ordering from wholesaler (also run by the company) to individual shops. Everything in wholesale warehouse runs on the same DOS thing too, with stock inventory, invoice, ordering, ... There's already plan to (finally!!) put it to sleep and replace with something newer and more flexible, but given how low on resources and manpower the company is, it's not going to happen fast.