Here's a similar one we use a lot in all sorts of slide sets at Facebook: http://imgur.com/a/EN0G8

(Stolen from Pedro's "Notes from Production Engineering" talk: https://www.youtube.com/watch?v=ugkkza3vKbc , Pyramid shows up around 47:30 min PE = Production Engineer. It's a similar role although not exactly the same as the usual SRE role.)

It's a bit of a different view on the same underlying work. Interesting to see how they slightly differ.