Maps are generated at irregular intervals now, due to problems with the map generation. Usually, the area between x,z=-6000 and x,z=6000 is mapped. Since 2019-07-09, maps are being generated between x,z=-7008 and x,z=7008.
Worldmaps can be found at minetest.bananach.space. the out.svg file also overlays the railway map, for best viewing, download both world.png and out.svg and view them locally on your computer.