Neither Maglev nor GFE are usually tied to a specific service nowadays, so it could still be either of them. Way back when, some teams or services such as Check

Neither Maglev nor GFE are usually tied to a specific service nowadays, so it could still be either of them. Way back when, some teams or services such as Checkout had to run their own private pool of GFEs. Given Urs' mention of backends, I am slightly inclined toward GFE.