The skiing season is almost upon us, with The Lecht and Cairngorm having opened for last weekend. I was aware of some problems with contour rendering on OpenPisteMap, but now it seems it is affecting the rendering of the actual pistes too. Comparing 2 zoom levels of the same area:
http://openpistemap.org/?lat=46.09542&lon=7.24663&zoom=14&layers=B000
http://openpistemap.org/?lat=46.09542&lon=7.24663&zoom=15&layers=B000
Some of the pistes just aren't rendering in some zoom levels.

My only guesses are that either Mapnik or the PostGIS spatial index is broken. Unfortunately, if it is the latter I suspect I'll have to drop the whole database and start from scratch. :(