I want to take this opportunity to complain about the interview system. Hire people who care about the product and company. Such mistakes cannot be made by people who care.
It's funny. You know it. I know it. Entire HN knows it. And yet _no_ interview follows any such common sense rules. Just go to a Google/FB interview and they ask you all sort of questions. It doesn't matter what you are interviewing for. In fact, in many cases they don't even tell you which group/team/project you will be assigned to. Since they will "assess" where you fit best.
I don't think that's true. A large portion of companies/hiring managers don't get this, all the way down to actual engineers.
I've come to believe it's largely a "if I had to go through that BS, you do too!" tit for tat thing engineers now play.
Disclaimer: I work for Google
At Google this just isn't true unless we are talking about new grads. After you pass the interviews, you have to do team matching, where you will have informal 2 way interviews with prospective teams. Only after you find a team that you like and that likes you can you get an offer, assuming your application is approved.
It's definitely not a case of sticking you in a team without your input. It's true that at the interview stage you won't know, but by the time you have an offer you know what team you'll be on.
I believe at Facebook you have even more freedom. You get to go to boot camp for 3 months and after that get to choose what team you want to be on. I haven't worked there so this is just based off what recruiters and friends have told me though so hopefully someone else can correct me or elaborate.
BTW, I think that second point is a common misconception that deserves rebuttal because I think that until a five years ago or so Google wouldn't tell you which team you would join (or give you much choice) before deciding on an offer, even if experienced.
Writing B+ trees at the drop of a hat is probably more a signal of memorization and recency of taking a data structures class than smarts, particularly the smarts necessary to develop and maintain robust distributed infrastructure.
2. The number of people at Amazon who need to be able to choose a search/sort/etc. algorithm or data structure and understand why one is more appropriate than another for a given use case is much higher.
3. The number of people at Amazon who need to demonstrate common sense is very high. This skill is much more closely related to #2 than #1.
CS fundamentals are nice to know, but how often does one implement something custom like BigTable/Colossus from scratch vs. buy/use OTS? The support/scalability/technical debt/unforeseen costs of implementing something entirely new is typically much greater than using adequate "lego" that already exist.
Judgement of cost/benefit DIY vs. OTS can be gained (hopefully) without too much wasted effort, time, money, morale & business life-expectancy.
That's a very naive assertion. Humans make mistakes, they always have and they always will, no matter how smart they are and how much they care. That's why pilots have checklists that they go through before they're even allowed to leave the gate.
Of course no one who cares would intentionally make the choice of building the status page on the infrastructure that it monitors, but it's not that difficult for something to creep into the dependency chain and then you don't find out until the next outage a year later.
Mistakes were made, but attributing it to lack of caring is misguided. Good intentions don't work, you need mechanisms to enforce good practices. Those mechanisms obviously failed here, but the solution is to fix the mechanisms, not ask people to care more.
[1] http://www.ww2hc.org/emailarchives/2011/checklistorigin.htm