Artillery outpost for late game expansion.
Will automatically open the supply train station and stop firing when supplies run low. An artillery train station is there to allow temporarily parking extra firepower there.
One mod is used in the blueprint: "More Long Inserters". The long handed stack filter inserters help get good throughput when unloading the mixed supply wagon. Regular filter inserters would work too if you drop some of the less critical supply boxes that rarely get used but with this setup it can autonomously repair any item in the outpost.