As part of a security upgrade, I'll be rebooting the systems that host Wikitech and Horizon in about two hours, at 14:00 PST (16:00 CST).
Those websites will be briefly unavailable, as will be the Nova api. This last will cause a brief interruption to the WMF Continuous Integration system. The total downtime should not exceed 10 minutes.
Sorry for the interruption!
-Andrew