Use when deciding whether a computer-systems project belongs at ATC (ACM SIGOPS Annual Technical Conference, formerly USENIX ATC) or should be routed to OSDI, SOSP, NSDI, EuroSys, FAST, or a workshop like HotOS/HotStorage — distinguishing ATC by its broad practical scope, its Deployed Systems / experience lane, the breadth-vs-selectivity trade, and the November/June calendar.
