This. Absolutely this. Working on large distributed system can be both exhilarating and exhausting. The two often go hand in hand. However, working on such syst

This. Absolutely this. Working on large distributed system can be both exhilarating and exhausting. The two often go hand in hand. However, working on such systems without diligence tips the scales toward exhausting. If your testing and your documentation and your communication (both internal and with consumers) suck, you're in for a world of pain. "But writing documentation is a waste of time because the code evolves so fast." Yeah, I hear that, but there's also a lot of time lost to people harried during their on-call and still exhausted for a week afterward, to training new people because the old ones burned out or just left for greener pastures, to maintaining old failed experiments because customers (perhaps at your insistence) still rely on them and backing them out would be almost as much work than adding them was, and so on. That's not really moving fast. That's just flailing. You can actually go further faster if you maintain a bit of discipline. Yes, there will still be some "wasted" time, but it'll be a bounded, controlled waste like the ablative tiles on a re-entry vehicle - not the uncontrolled explosion of complexity and effort that seems common in many of the younger orgs building/maintaining such systems nowadays.