3.1/ Mike on Facebook Engineering: “I will say a thing about this two, an interesting anecdote about Facebook culture is that I think many of the very best engineers in Facebook's history were also the cause of catastrophic engineering failures.”

3.2/ Harkens back to MS: “I remember there was this element of lore. I don't know if it's still true … Excel was written in hand-tuned assembly. There was something like 91 global variables in Excel that were protected by one spin lock. No one could unravel the hairball.”

3.3/ “That was I think you're still limited to 256 columns in Excel, because of the morass at the very center of it.” My comment: 😲😲😲