Live data from Hacker News

Bug squash: An underrated interview question

blog.jez.io

1–10 of 282 posts

Re: Bug squash: An underrated interview question

#2
I like this approach far, far more than coding tests!

> It’s fun. It’s fun in the same way an escape room is fun. It’s fun because of the dopamine you get when the test suite blinks green.

Keep in mind that for lots of people in a job interview setting (even excellent candidates) this is not fun, this is stressful. It may be fun on the job or at home, but the stress of a job interview both eliminates any "fun" aspect and makes even simple tasks more difficult. Just mentioning that to encourage some amount of empathy and understanding for the candidate.

Re: Bug squash: An underrated interview question

#3
I wonder if this is an improvement over a conventional white boarding question.

It seems to me that debugging in particular is often dependent on the developer realizing some edge case or scenario where things circumstances line up to produce a bug. In that case, wouldn't a "bug squash" end up being similar to a "gotcha style" white boarding question.

The author, quite correctly, says that the interview should be scored not on whether the candidate can immediately vomit up a solution but on whether they can demonstrate their an organized thought process. However, isn't that true of white board questions as well?

Overall, it seems to me that the real problem with conventional white board questions is when the interviewer focuses on whether the candidate gets the right answer rather than on whether they demonstrate the ability to problem solve. While it sounds like the author is a good interviewer who focuses on assessing the candidate's thought process, it's not clear to me that giving debugging questions is actually what causes that.

Re: Bug squash: An underrated interview question

#4
Although I like this interview question, it has a big downside. You make the candidate spend quite a lot of effort while you as an interviewer don’t learn much. The answer to “Can this candidate find and fix this bug?” is not necessarily equal to “Is this candidate a good expansion of the team. What do they bring that we need?”

Re: Bug squash: An underrated interview question

#5
post #4

Although I like this interview question, it has a big downside. You make the candidate spend quite a lot of effort while you as an interviewer don’t learn much. The answer to “Can this candidate find and fix this bug?” is not necessarily equal to “Is this candidate a good expansion of the team. What do they bring that we need?”

It's kind of a fizzbuzz-ish weed-out question: If they can do it, sure, you haven't learned that much, but if they cannot, then you know with pretty high certainty that they're not going to add to the team.

Re: Bug squash: An underrated interview question

#6
This is one of the interview questions at Stripe, and I agree that it was the most "fun" part of the interview (It is still pretty stressful giving an interview, but magnitude times much less so than converting a BST to doubly linked list, and converting it back )

Re: Bug squash: An underrated interview question

#7
> You’ll need at least one question per language that you want to allow people to interview in. ... “Was this performance poor because they’re bad at debugging, or just unfamiliar with this language’s tools?”

Not necessarily a con. Different languages/tech stacks have very different tools. I.e. debugging a GC issue is different than debugging a network issue is different than debugging an embedded issue. If you chose a language for a very good reason, then it's not a con to filter out those who aren't familiar with that language enough to debug an issue in it

Re: Bug squash: An underrated interview question

#8
I was thinking, wouldn't it be fairer to do the test in an online code sandbox where being able to build and install isn't an issue? Then I thought, isn't letting the candidate use their own machine and debugging tools about as biased as hiring a limo driver based on how fast they can drive their own car? It does tell you who's a real "car guy" or "Unix guy", it just has a slight disparate impact by screening for people with money and hobbies. I mean, I think you should be allowed to hire these people because they will be better at the job, but hopefully they could also show that in a sandbox test.

Re: Bug squash: An underrated interview question

#9
post #4

Although I like this interview question, it has a big downside. You make the candidate spend quite a lot of effort while you as an interviewer don’t learn much. The answer to “Can this candidate find and fix this bug?” is not necessarily equal to “Is this candidate a good expansion of the team. What do they bring that we need?”

To me this sounds like a relaxing break from the effortful part of the interview.

Re: Bug squash: An underrated interview question

#10

> You’ll need at least one question per language that you want to allow people to interview in. ... “Was this performance poor because they’re bad at debugging, or just unfamiliar with this language’s tools?” Not necessarily a con. Different languages/tech stacks have very different tools. I.e. debugging a GC issue is different than debugging a network issue is different than debugging an embedded issue. If you chose…

> If you chose a language for a very good reason, then it's not a con to filter out those who aren't familiar with that language enough to debug an issue in it

The language is based on/chosen by the candidate. We want to map the candidate to whatever language in our repository of "this question in different langs" is closest, to control for the candidate's familiarity as much as possible.

If you're screening to only candidates who can code in the language your company primarily works with, you're missing good candidates. The best are going to be able to pick up a new language rapidly, particularly if your language is a mainstream one that's probably imperative or OO-ish, or both; adding a non-esoteric language to one's repertoire is just not that hard a thing to do. But in the interview, I don't want them struggling with syntactic bull, as it's not a useful signal; I want to know how they think, whether they've seen code before, and can they reason from problem statement to debugged bug.

Post reply on HN