9 ms·

So accurate. I'm a grad student who studied security deeply during my time in school. I want to keep my hands on a keyboard and I don't like airplanes (which r

by theboss 13y ago

So accurate. I'm a grad student who studied security deeply during my time in school. I want to keep my hands on a keyboard and I don't like airplanes (which rules out consulting) so I've applied at a lot of companies to be a ``security engineer''. I can't tell you how many well-respected companies ask me to write min-heaps, depth-first searches, etc. I don't understand what they are asking me this for...It isn't even close to a realistic representation of what my day-to-day responsibilities would be. It is also an immediate turn-off....

jw2013 13y ago
Similar story here. Now not only these "big" companies as Facebook, Google, Microsoft focus mainly on algorithms and data structure during interview, to my surprise some of the early startups ask heavily for whiteboard coding... It's no surprise these companies rejects many really good hackers (at least from people I know... yes, I admit the small sample size) and accepts these just optimize for algorithm preparations by doing a set of online coding problems.
- rhizome 13y ago
  The startup industry saw the same kind of interviewing voodoo in the 90s, copycatting how Microsoft conducted them.
- deleted 13y ago
  [deleted]
GFK_of_xmaspast 13y ago
They're asking you that because there are lots and lots of candidates who look great on paper but don't actually know anything. I have personally met several. I wouldn't ask a candidate to implement a min-heap (mostly because it's kind of obscure and I'd have to think about it) but a depth (or breadth) first search is something I'd expect any competent candidate to rattle off in a heartbeat, just because it's such a fundamental cs principle that gets used in lots of places and, unlike things like sorts, doesn't really have a good library to fall back on in practice.
- theboss 13y ago
  Believe me, I can and do implement them, but I always do so backhandedly. ``I am a security engineer, what does this have to do with security''. In reality, I have not accepted an offer from any companies who ask me these questions because most of the positions are not exactly what I am looking for. Also, I tend to disagree. Some of the best security guys out there never went to college. It's hard to expect these guys to know algorithms and datastructures even if they are really gifted exploit developers, or the like. edit: To clarify. What this really shows is that I am not being interviewed by a security person...ie there is no special interview process for my position compared to a regular software engineer.
  - gaadd33 13y ago
    I doubt "the best security guys" end up with the same interview experience. If you are widely known in the industry as an expert or the best at something I think the process to obtaining a job is significantly different from someone applying for jobs.
    - tptacek 13y ago
      Not here. I am way more scared of the "best" candidates than I am of the normal ones.
      - gaadd33 13y ago
        Really, that's surprising to me. Would people of Bruce Schneier/Fyodor/et al stature go through the same interview process that everyone else goes through? I'm pretty sure they wouldn't at a big company but you guys do things differently (for the better it seems) so maybe?
        tptacek 13y ago
        Yes, they would. I am 100% sure of it.
        pgeorgi 13y ago
foobarian 13y ago
I don't understand how there can be a good hacker that does not, at least on some intuitive level, get such basic data structures or algorithms. I don't mind if someone doesn't know what depth-first search is, but I should be able to explain it quickly and they should be able to come up with at least pseudo code. The relevance of this to software engineering roles just seems too great. Cramming these questions online does not work. I don't know what Facebook/Google et al are doing but I can spot a candidate who studied interview questions from a mile away. They may bang out a DFS by rote but that's just warmup; they should be able to talk about details, deal with changing requirements, discuss the algorithm/efficiency/design of their solution, be able to talk about underlying data structure primitives, etc. To be fair the grandparent was talking about a specialized position in security engineering for which the generic coding interviews could be a bad match.
- Mvandenbergh 13y ago
  Sure, but these tests are necessary without being sufficient. I'd expect that performance in these tests is predictive up to a certain level but that being really good at them versus just performing decently is not nearly as predictive for actual job performance.
- eli_gottlieb 13y ago
  >I don't understand how there can be a good hacker that does not, at least on some intuitive level, get such basic data structures or algorithms. And I don't understand why someone who spends his time up to the eyes in crypto proofs, exploit code, and research articles should have to cram for an Algorithms 1 exam for each interview. I've seen these questions used well (had a neat discussion with a start-up CEO in Boston once about reimplementing a toy Twitter in Scala), and really brilliantly (another start-up in Boston once asked me to describe my favorite algorithm and got a short, ad-hoc tutorial in lottery scheduling), and really, really badly (BigCos asking stuff you'd see on an undergrad-level exam from years and years ago). Strangely enough, I'm praising the two startups that didn't offer me a job (though I'd really like to reapply to that second one), and condemning the BigCos (you know who I mean) that did offer me a job.
- theboss 13y ago

by theboss 13y ago

jw2013 13y ago

Similar story here. Now not only these "big" companies as Facebook, Google, Microsoft focus mainly on algorithms and data structure during interview, to my surprise some of the early startups ask heavily for whiteboard coding... It's no surprise these companies rejects many really good hackers (at least from people I know... yes, I admit the small sample size) and accepts these just optimize for algorithm preparations by doing a set of online coding problems.

rhizome 13y ago
The startup industry saw the same kind of interviewing voodoo in the 90s, copycatting how Microsoft conducted them.
deleted 13y ago
[deleted]

GFK_of_xmaspast 13y ago

They're asking you that because there are lots and lots of candidates who look great on paper but don't actually know anything. I have personally met several. I wouldn't ask a candidate to implement a min-heap (mostly because it's kind of obscure and I'd have to think about it) but a depth (or breadth) first search is something I'd expect any competent candidate to rattle off in a heartbeat, just because it's such a fundamental cs principle that gets used in lots of places and, unlike things like sorts, doesn't really have a good library to fall back on in practice.

theboss 13y ago
Believe me, I can and do implement them, but I always do so backhandedly. ``I am a security engineer, what does this have to do with security''. In reality, I have not accepted an offer from any companies who ask me these questions because most of the positions are not exactly what I am looking for. Also, I tend to disagree. Some of the best security guys out there never went to college. It's hard to expect these guys to know algorithms and datastructures even if they are really gifted exploit developers, or the like. edit: To clarify. What this really shows is that I am not being interviewed by a security person...ie there is no special interview process for my position compared to a regular software engineer.
- gaadd33 13y ago
  I doubt "the best security guys" end up with the same interview experience. If you are widely known in the industry as an expert or the best at something I think the process to obtaining a job is significantly different from someone applying for jobs.
  - tptacek 13y ago
    Not here. I am way more scared of the "best" candidates than I am of the normal ones.
    - gaadd33 13y ago
      Really, that's surprising to me. Would people of Bruce Schneier/Fyodor/et al stature go through the same interview process that everyone else goes through? I'm pretty sure they wouldn't at a big company but you guys do things differently (for the better it seems) so maybe?
      - tptacek 13y ago
        Yes, they would. I am 100% sure of it.
      - pgeorgi 13y ago

foobarian 13y ago

I don't understand how there can be a good hacker that does not, at least on some intuitive level, get such basic data structures or algorithms. I don't mind if someone doesn't know what depth-first search is, but I should be able to explain it quickly and they should be able to come up with at least pseudo code. The relevance of this to software engineering roles just seems too great. Cramming these questions online does not work. I don't know what Facebook/Google et al are doing but I can spot a candidate who studied interview questions from a mile away. They may bang out a DFS by rote but that's just warmup; they should be able to talk about details, deal with changing requirements, discuss the algorithm/efficiency/design of their solution, be able to talk about underlying data structure primitives, etc. To be fair the grandparent was talking about a specialized position in security engineering for which the generic coding interviews could be a bad match.

Mvandenbergh 13y ago
Sure, but these tests are necessary without being sufficient. I'd expect that performance in these tests is predictive up to a certain level but that being really good at them versus just performing decently is not nearly as predictive for actual job performance.
eli_gottlieb 13y ago
>I don't understand how there can be a good hacker that does not, at least on some intuitive level, get such basic data structures or algorithms. And I don't understand why someone who spends his time up to the eyes in crypto proofs, exploit code, and research articles should have to cram for an Algorithms 1 exam for each interview. I've seen these questions used well (had a neat discussion with a start-up CEO in Boston once about reimplementing a toy Twitter in Scala), and really brilliantly (another start-up in Boston once asked me to describe my favorite algorithm and got a short, ad-hoc tutorial in lottery scheduling), and really, really badly (BigCos asking stuff you'd see on an undergrad-level exam from years and years ago). Strangely enough, I'm praising the two startups that didn't offer me a job (though I'd really like to reapply to that second one), and condemning the BigCos (you know who I mean) that did offer me a job.
theboss 13y ago