Miner is used worldwide and in German as well; Austrians speak of a Miner when they mean an ASIC device or the business running it. That double sense gives the name range: it can front a hardware shop, a hosting service or an operating company. The word is short, spelled the same in English and German, and needs no explanation. The .at ending connects it to Austria, where hydropower makes up a large share of electricity generation.
The domain sits in the mining category and belongs to the Bitcoin Mining DACH set, which brings mining terms for the German-speaking region together. It fits companies that operate their own machines, offer hosting for private miners, use waste heat from mining in heating projects, or sell and repair ASIC hardware. An education project on home mining would also suit it.