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Engineering whiteboard interviews: yay or nay? (keyvalues.com)
196 points by lynnetye 7 days ago | hide | past | web | favorite | 355 comments





  VP of Engineering at Eaze, previously CTO at Getable and engineer at Yammer.

  No, not at all. Whiteboard interviews test one thing
  well: How well does a candidate code on a whiteboard.
  Engineers on my team never have to code on a whiteboard
  (whiteboards are really bad at running code), why would I
  make candidates do something that I don't ask the
  engineers already on my team to do?
This comes close, but I think the real issue that most of these reasons aren't hitting on is that software development is typically done asynchronously. Whether it's a whiteboard or a computer connected to a projector or TV or a live peer coding session it doesn't matter: if done in the interview, it puts the candidate on the spot in a way that they rarely (if ever) will be on the job. Developers typically are able to take time by themselves or with trusted/known colleagues to solve a problem. There are very few opportunities to get over performance anxiety related to coding in front of others that we don't know.

> Whiteboard interviews test one thing well: How well does a candidate code on a whiteboard.

What if you consider part of someone's job to be communicating concepts to people, possibly with the help of visual aids and diagrams?

I hate this concept that if it's not typing code into an editor then it's not "real work".

I absolutely communicate with my coworkers using a whiteboard and pseudocode. I reject the idea that being put on the spot is necessarily "artificial". To the contrary, I think that the number of engineering jobs where you can assume you'll never be put on the spot or have to communicate complex ideas verbally or visually is relatively low.

Now if this particular skill isn't interesting to an employer and they'd rather spend the time talking about some other candidate capability, that's a whole different story.


Ugh, communicating with a whiteboard has no overlap with developing a solution to a completely unexpected quiz (if you didn't cheat) on a whiteboard in front of someone scrutinizing your every move with your future career on the line.

Whiteboard interviews rarely test the ability to communicate on a whiteboard because the interviewer knows the answer they are looking for and the presenter does not.

If you defend whiteboard leetcode using this excuse you are deluding yourself and you are part of the problem. The only thing the modern FANG interview hires for is people that can solve algorithms problems in a silo under pressure. No checks for software engineering skills, collaboration skills, testing skills, reviewing skills, and on and on...

The whiteboard interview is why so many engineers unexpectedly suck.


> Whiteboard interviews rarely test the ability to communicate on a whiteboard because the interviewer knows the answer they are looking for and the presenter does not.

They you are asking the wrong questions. I use whiteboard for developers, and for junior developers I give them a simple task such as reverse an array, turn a string into a palindrome (and explain what it is if they don't know). If they want to be a developer they must be able to solve those simple tasks. I don't really care how, as long as they think loud. Then I use it as a starting point for enhancement discussions, perhaps stack/heap questions, recursion, assignments ect. During all this I coach them, teach unknown concepts in simple terms - this is what they can expect when they ask their mentor a question so in that sense they get a feel for us too.

Some argue that it's still not good, and that we're filtering out people that work best alone. That is true, but that is by design. We work as a team, having 10 individual developers not working together unless forced is an architectural nightmare.


If you think someone looking over your shoulder while you solve a problem with your future career on the line is anything like "working as a team", I weep for whatever work environment your developers work in.

So a simple problem solved while communicating, asking for clarification, and telling your thoughts is "someone looking over your shoulder while you solve a problem"?

I'm not asking them to impelment van Emde Boas tree because I spend countless of hours implementing and analyzing it getting my degree. I ask them to turn a string into a palindrome, or return the sum of all even index in an array of ints, ect. They're free to ask all the questions they like. It's a litmus test to see if they know simple programming, akin to seeing if a contractor knows how to drive in a nail using a hammer.

Is it high pressure while your future career is on the line? Absolutely, but they are not special snowflakes, and it's the case for any interview for any kind of position. I'm not going to throw thousands of dollars after someone just to figure out that they have in fact never written a functioning for loop.


Agree with most of what you said except the conclusion.

The reason many engineers unexpectedly suck is because it’s a high paying job where performance is difficult to measure let alone predict.

White boarding interviews are a symptom of the problem, not the cause of it.


I always thought it would be a good idea for the interviewee to also come up with a question and then have the interviewer try and solve it with their guidance. I imagine it may be more helpful than the other way around.

If the interviewer leaves frustrated because they couldn't solve anything and it was a mess, or the question was formulated terribly, or the interviewee was under prepared, etc etc, then it provides a lot of insight into the capabilities of the interviewee. It almost provides more insight into the qualities required of a developer than just putting them on the spot.


>I reject the idea that being put on the spot is necessarily "artificial". To the contrary, I think that the number of engineering jobs where you can assume you'll never be put on the spot or have to communicate complex ideas verbally or visually is relatively low.

I think it's safe to say that being put on the spot in front of people you don't know who are judging you is quite different from being put on the spot in a team meeting with someone from product who will watch your demo of a potential new project/idea/concept.


We do whiteboard problems, BUT we also emphasize beforehand that the interviewers in the room are there to work through the problem with them. This is meant as more of a conversation, we're less concerned about getting to the "right, fastest, or most optimized" answer. Not a hard problem, no mindgames, no syntax rules, and no complicated pre-known algorithm work other than an if and a loop. Let's just talk about some pseudocode.

We've never rejected somebody for having a "bad" answer, because they were able to at least talk about what they're doing. We have had people flat out refuse to even try, and that seems like a pretty big red flag.


Every time an interviewer has told me something like this, they then nitpick syntax and appear to be primarily concerned with "does my whiteboard code compile" sorts of problems. And getting stuck / asking for help feels like I get docked for getting stuck. Same with less optimized. So it's hard to trust such an explanation - clearly my interview would be better if I came up with the perfectly optimized solution, or gave a lecture on the options rather than trying to discuss options.

So it seems to me entirely reasonable to still be nervous.

Mind you, I don't have a better answer, but I don't think just explaining that suboptimal is ok and it's a discussion really helps.


All these discussions conflate a related, but separate problem with tech interviewing: most tech interviewers don't have much experience interviewing, and have never had good coaching on interviewing, and as a result mostly suck at it.

Picking on whiteboard code for not compiling is not good interview technique. But it's also a common enough failing that it's hard to say a bad interviewer in that regard means a bad workspace, unfortunately.


Bad workplaces are so common though that it’s a perfectly good heuristic to guess that if a place asks you to do whiteboard questions it’s a bad engineering workplace. You’re not missing much by passing, and the heuristic probably won’t be wrong much.

I guess you think every major tech company is a bad engineering workplace? Seems like a broad brush.

Is it even disputed anymore that the experience of working at the big tech companies is abjectly awful? I mean, you gotta work somewhere and they “are fine” and you might as well try to get paid well, but that’s a far cry from a workplace that stands out as good.

The only place I’ve worked that was “good” instead of “treats people poorly but where else are they going to go” was a small, boutique financial company.

Small companies that are randomly led by non-dummies are the best, but are exceedingly rare. Out of the vast majority comprising the other stuff, it’s mostly all so miserable that you’re doing yourself a favor to skip it unless the pay is some dramatic increase for you or you otherwise have some emergency requiring you to take some job.


Of course it’s disputed. There are lots of happy employees of tech giants. Any company with thousands and thousands of employees is going to have a wide variety of teams of varying qualities.

(And yeah, the pay makes a difference. Not a lot of places where you can make a few hundred thousand dollars a year.)


I work for a large tech company and don’t know of any company like that with a large number of employees happy with their company.

(I’m making a distinction between the idea that a job “is fine” where one “is happy” merely because the culture is at least not worse than elsewhere while the pay is better vs actually feeling positively about one’s company’s culture and corporate behavior.

For example, my friends who work at Facebook are “happy” with their jobs, mostly because of pay and because they know if they switch to other companies, politics, corporate misbehavior, etc., will just continue. But these same people tell me frequently how sad, upset, soulless, disappointed they regularly feel because of their employer.

That feeling I think is extremely widespread in tech, almost all employers. That’s the only part in my viewpoint that matters for whether someone “is happy” at their job, and it’s that type of bad culture I think can be easily flagged by little stuff, like bad whiteboard interviews.)


I blame the modern attempt to turn software developers into assembly-line workers. With sprints and tasks and momentum and a million tiny cuts that take the innovation out and replace it with anonymous criticism and process over product.

I largely agree. Modern companies are set up to cargo cult lots of process and pay lip-service to innovation while taking extremely risk-averse and conservative approaches to practically everything they do.

Nobody has any idea what’s going on; nobody has clarity. And when someone does have clarity, middle management is only interested if they can set it up like a battery to harvest credit from. If they can’t, their incentives are usually more aligned with intentionally abusing process to “manage out” innovative people.


seems true

I wouldn't go as far to say whiteboard interviews == bad company. I will evaluate the company if a whiteboard interview is run poorly however and consider it a bullet dodged.

going through / having just gone through this process this is where i've basically ended up as well... crappy interview experiences are universal enough that they don't disqualify a company automatically (though obviously i'm not terribly fond of them :-).

the one thing i'd add is that i do take particularly thoughtful / empathetic interview processes, interviewers who actually know and understand the question (rarer than you'd think), etc. as a fairly strong signal, as those sorts of things don't just happen by chance-- they are the byproduct of a culture of thoughtfulness (and thoughtful people tend to be thoughtful about most things).


I caught an interviewer red handed once by handing him the marker and asking him to show me. He tried and failed and then his coworker tried to fix his mistake and failed.

Ya I did not get that job lol.


By the time we get to the whiteboard problem we've already assessed technical skills as well as we can. The whiteboard problem is to test their fit on the team. It has worked well for us and certainly weeded out some people who could have been problematic culturally. Is that a "failing?" Maybe we lost some more technically skilled individuals that way, but our team isn't exactly lacking because of it.

This is generally the same experience I have had. I'll even talk through the assumptions (e.g. "Can we assume I know how to do argument checking?") and then after I've done the heavy-lifting of the problem-solving I'm now discussing how I didn't do something I brought up as an assumption.

Also, generally, if I'm whiteboarding in front of my coworkers/team/etc. I'm discussing something I've thought about for more than the few moments I have to digest the question while standing at the board during an interview.


Even if you didn't say

> Can we assume I know how to do argument checking?

I would probably question you at some point about a particular value of an argument and almost all candidates will get points for thinking out load that of course a NULL would get it crashing and that a simple check could stop it. Then it leads to discussion about how it should be handled. Sometimes a NULL means the program should cast an exception, other times it should just return without any side effect.

IMO the hate for whiteboard questions is really a symptom of poor interview technique.


Writing down the assumptions can help.

Maybe I was just lucky, but I interviewed with google and dropbox recently and both companies gave me laptops to type in, did not ask me once about if my code compiled, didn't comment on my style, nor did I have to perfectly know the standard library (for google, they told me to just guess at the random library functions and I also forgot some of the functions names for a set. For dropbox, one of the guys re-explained to me semaphore functions and how they worked since I forgot since it had been so long since I used them in college). I passed both.

Granted, I will give you that optimized code has definitely been important. One of those interviews even had me use a bit array (at least I think it was that) to efficiently a store a list of booleans but at least they gave me the relevant function calls to use an already implemented one.


> clearly my interview would be better if I came up with the perfectly optimized solution, or gave a lecture on the options rather than trying to discuss options.

Right. And a competency based interview goes better if you have a perfect example for every question. But it isn't an auto-fail if some of your answers are mediocre

Personally though - I'd rather hire someone who is able to properly communicate their thought process over an imperfect solution, than someone who was unable to discuss/explain the perfect solution they scrawled down.


Give feedback to the company.

When I give interviews candidates often say they don't remember some API. I tell them I don't care and they should make something up and I'll figure out what they are doing from context. The only time this burns candidates is when they clearly don't understand an ADT well enough to give it a sane interface.


That sounds like a much better way of handling a whiteboard problem.

In my most recent on-site interviews, my interview would be in a room with full floor to ceiling glass windows, the next interviewer would come in, ask one or two personal questions, and then either cut me off after a couple minutes or just simply say "we're going to move on to the whiteboard now, do this". Meanwhile people are walking by staring into the room, looking at the whiteboard, etc.

Which is just too rigid, IMO.

When I interview a candidate, I want to know that they'll be able to work together with myself and my current teammates as a team. So I would rather do something similar to what you described.


Yeah, that's the trick. It isn't a technical exercise really. Its really a communication/team fit test.

You are asking the candidate to compartmentalize their thoughts to solve a toy problem during a period of time when they are attempting to put various nascent clues about your organization together in order to form a better understanding and to identify how they can provide value / fit into the flow.

Fizz-buzz tests have their place, but I think an onsite interview is past that point. In general I have found that white board exercises don't allow me to either understand or convey how I can apply my expertise to provide value for the organization.


Agreed. For us this is a communications/team fit exercise and not a technical exercise. It has done a good job of filtering out bad fits, like the guy who refused to talk to the women on our team regarding anything technical.

As a candidate, to me, that sounds a lot like, "we're going to do the same things we would normally do in a technical interview, but we're going to evaluate you based on random, arbitrary, subjective criteria that you will never know about rather than your actual level of skill."

I'll bite: yes, if there's rapport and the candidate doesn't feel caught off-guard or needlessly pressured. If it's whiteboarding like you'd whiteboard while on the job with your coworkers, that's a good idea that can tell you a lot about a candidate. Unfortunately, in my experience, that doesn't seem to happen very often. A lot of people seem to treat it as an adversarial process or expect, for lack of a better description, a "performance" over contrived problems.

I've had my share of the second kind, which were without exception some of the most unpleasant interviews I've ever gone on.


> We do whiteboard problems, BUT we also emphasize beforehand that the interviewers in the room are there to work through the problem with them. This is meant as more of a conversation, we're less concerned about getting to the "right, fastest, or most optimized" answer. Not a hard problem, no mindgames, no syntax rules, and no complicated pre-known algorithm work other than an if and a loop. Let's just talk about some pseudocode.

If only all interviewers were like you.


We do the same thing as well. As long as the candidate can explain their abstractions in pseudo code we are good. We also keep to a 1-1 between interviewer and candidate so that the candidate isn’t intimidated.

I’ve interviewed at Facebook as well and although the interview was not successful I have never been nitpicked about syntax and compilabiltiy/runnability of my whiteboard solutions. I came off with a very healthy appreciation of the way they try to engage the candidate and reduce stress.


> We do whiteboard problems, BUT we also emphasize beforehand that the interviewers in the room are there to work through the problem with them.

Except at the end of the day this is an interview, you are judging their answers and evaluating their performance. I have been part of white boarding sessions like this and it does not reduce anxiety and still feels completely removed from what I actually do on a daily basis.


Not judging their answers. The only thing we're judging is their ability to communicate in a group setting similar to what happens on the team on a regular basis.

We at least on a weekly basis somebody has some small problem they need help working through, it generally ends up being diagraming or pseudo-coding to figure out the best approach. If somebody can only participate by hiding in a corner typing out code, then the process worked for both sides.


Well, when you first start your job, you won't really know the people you are working with so I don't see how it is that much different.

Incredibly different.

I highly doubt a normal engineer is going to be giving a demo to their team with high stakes in the first three or so months. I understand if they're possibly a senior engineer, architect, or lead of some sort because they were probably hired with a plan to spearhead a specific project.

I'd say in the average case a new engineer will have enough time to at least break the ice with their new team before being put into a high pressure situation.


I gave a demo of my intro project after a month to my 100 person org at my last company and I was a new grad. In fact, when I was an intern, all interns did project demos at the end of their internship.

Was a hundred K on the line? Clock ticking? Random subject you couldn't have/hadn't prepared for? :D

Was the presentation of that demo standing between you and being fired or keeping the job?

I communicate my ideas using a whiteboard too. But I never produce those ideas using a whiteboard in front of my coworkers under pressure of being fired.

Well this is hardly the fault of white board interviews. That’s just interviews. Any interview (regardless of the style) is going to be in front of “coworkers” and “under pressure of being fired.”

That’s just interviews.

Nope. There was a great submission a few years ago about a guy who applied to two categories of jobs: management and software development.

In the SD roles, everything was oriented toward rejecting him. Any possible "red flag".

In the management roles, the interview was focused on finding areas where he could contribute to the company.

Whiteboard interviews are a problem in and of themselves, and the propagate terrible attitudes into the rest of the interviewing process.


hfdgiutdryg any chance you can find the link to that submission? It sounds fascinating, and I couldn't find it via HN search.

The "produce the ideas during the interview" part is the fault of whiteboard interviews. There's nothing that says an interview should cover brand-new material as opposed to material the candidate is supposed to be familiar with.

If communicating ideas is part of your job, I'd bet any amount that you decide what ideas you want to communicate well before you do the actual presentation (or other physical delivery of the ideas).


My experience agrees with this. I am a different, significantly less comfortable person to be around when strangers are asking me so many questions about myself. I think it’s just about the worst way to get to know me.

When I get hired this way, I always feel a little bit of guilt because I know they actually hired somebody else.

What can be done? I’m not sure, but I can say one thing: my level of discomfort is multiplied by the number of strangers in the room. Does this ever get considered with interviews?

I am far more comfortable coding in front of 1 or 2 people who each give me a little bit of background about their coding experience; just so I know. If they are experienced engineers, it’s probably not going to change what I say aloud, but it just makes me more comfortable. I guess more overlap of technologies in our background does help. It’s nice to not feel pressure of worrying if my solutions reflect general programming conventions enough to be language agnostic. I have never really used Java, for example.


Then test that. Having someone code on a whiteboard, even if they are explaining what they are doing while they go along, is simply not the same thing as being good at using on the fly visual aides while communicating. In any case, that isn’t coding either.

You have 40 minutes to make a slide deck that explains bloomfilters and 5 minutes to present in front of the director of engineering.

That is the same as saying who can code the fastest rather than who does the best job. But at the PhD level there will be a presentation given regardless.

It's bizarre to me that you think that whiteboard coding tests "communication", in any way. It's not like a presentation, or anything. It's one-sided combat where someone with a secret tries to get someone who doesn't know the secret to regurgitate the secret, on the spot, while pretending that s/he didn't memorize the secret in advance while cramming a great big "Cracking the Programmer Secret" book to prepare for the entire silly exercise in Kabuki theater.

If you want to test communication skills amongst programmers, I dunno...ask them to write something in coherent English. Or here's a crazy thought: ask them to document some code. I guarantee that 80% of working "rockstar coders" will fail (but not before whining, crankily, about how unfair it is that you would actually make them do such a useless thing, since, y'know...never actually documents anything IRL, dude).

Programmers like whiteboarding because it lets them believe that interviews can be reduced to purely objective functions, and because GooAmaSoftBook does it. They're too scared to deviate from the pack, lest people think they aren't as "elite" as everyone else.


> It's bizarre to me that you think that whiteboard coding tests "communication", in any way. It's not like a presentation, or anything.

I feel like we're probably at an impasse if I can't convince you that a whiteboard is a decent medium to communicate ideas around datastructures and algorithms, but I appreciate your point of view.

I can only say my experience, which I hope you will take into account as one anecdote. I don't read books about "cracking the coding interview" or do leetcode or hackerrank. I left school 14 years ago or so my stash of cs trivia/secrets/gotcha isn't particularly full. I've done whiteboard interviews where I come up with at best a naive solution.

And yet I've received offers for fairly senior engineering positions at Amazon and Twitter and (hopefully tomorrow) from Google. Most of the whiteboard interview isn't even around the code, although that's a small part. Most of it is analyzing the problem, discussing constraints, discussing tradeoffs, walking through data structure manipulations, drawing arrows and boxes, that kind of stuff. Some code, maybe 30% of the interview. I just keep having this experience where nobody wants to play the gotcha game, they want to know how well I can communicate while solving a problem and they think they get that information out of the interview (I agree with them).

That experience makes it hard for me to understand a viewpoint that believes that whiteboard interviews are about memorizing secrets in advance.


Have you considered that your experience interviewing at these places might have been atypical?

Every set of interview prep material I've seen from Facebook, Amazon and Google recruiters asking me to interview in the last 3 months has included links to things suggesting "cracking the coding interview" is a good start and pointing to similar docs otherwise.


> I guarantee that 80% of working "rockstar coders" will fail (but not before whining, crankily, about how unfair it is that you would actually make them do such a useless thing, since, y'know...never actually documents anything IRL, dude).

Are you sure you're not just replacing one stereotype with another here? Do you think it's fair to say that 80% of people who do well at whiteboard coding value documenting their software so little that they'd be fail at it while disparaging the concept?


I think that was hyperbole for emphasis, not a strong generalization as you imply. I've met and worked with plenty of programers up and down the scale of ability who think "code is self documenting."

There are plenty of things one can gauge candidates on via the whiteboard. System design, application design, psuedocoding implementation (or real coding, if necessary - it should be natural flowing from psuedocode to implementation though), problem solving with visuals to denote intuition...the possibilities are vast.

There seems to be a bunch of ingenuous assertions here that is characteristic of someone who doesn't think one should have to prove oneself. I'm at a FAANG and we don't even ask anything crazy hard for algorithms/data structures like Google or Facebook does, but our interviews still manage to be intense for technical and soft skills - they will challenge even strong candidates and one cannot pass the interview without displaying strong technical acumen or communication skills.

There is so much more to technical assessment than just coding. A whiteboard is just a standard medium for communicating ideas in a collaborative manner that still works the best for any sort of deep collaborative design when compared to any other medium so far.


or do a code review

Indeed. Or give a talk, or write a design doc, or...so many better options, all of which could be balanced out across a day of interviews.

Think how much you might actually learn about a candidate if your interview process replaced a day of solid whiteboarding with a code review, some pair programming, a session of documenting someone else's code, behavioral interviews, etc. It's almost as if you'd be treating them like a...person!


The point is that the interview style in question overemphasizes on-the-spot responses. How is prowess in a game of "gotcha" an important indicator of engineering skill?

I tend to agree with (what I think is) the sentiment of some of the respondents in the article: if your whiteboard interview is a game of gotcha, then the problem is your interviewer, not the whiteboard.

I think the complaint that programmers pretty much never have to think about code under pressure is a fair criticism. The whiteboard really puts you on the spot. But if it's your company and your hiring managers are playing a game of gotcha on the whiteboard, you need better interviewers.


State dependent learning is a bit of a factor too. I can count on one hand the number of times I’ve presented anything on a whiteboard at work, yet just about every company asks these questions during interviews. A screenshare would be a better representation of on-the-spot problem solving, if that’s what you’re testing, because I’m at least in an environment I typically work in.

Whiteboard coding interviews are one thing that I have to go out of my way to practice for and get better at over time when interviewing (ie over the course of a few failed interviews). I don’t feel more skilled or smarter by the end of the set of interviews, but I inevitably do better at these kinds of problems. Should the interview be testing my competency at day-to-day work skills or how well I’ve practiced my interview skills, because whiteboard coding problems only achieve the latter.


> A screenshare would be a better representation of on-the-spot problem solving, if that’s what you’re testing, because I’m at least in an environment I typically work in.

I do coding interviews in the following manner: I select an interesting problem from a book. I personally complete the problem, measuring what was challenging and the time it took for me to complete the problem. I check the textbook solution, making notes of how my solution differs from the textbook's. If I like the problem, and if it fits with the development role, I invite the candidate to bring a development laptop, I give them a hard time limit of twice the time it took me to complete it, and have them share their screen while they attempt to complete it.

Afterwards we test their solution, I ask them some questions about it. I grade based on code taste, the number of hints they need, and their completion time. All candidates for a position are given the same question. Performance in coding interview is about two third's of the overall candidate evaluation. The ability to sit down and write good code in a time constraint manner is a very important part of being a developer.


This would be a good method if your goal is to hire a carbon copy of yourself.

First, your definition of "interesting problem" probably includes a lot of personal biases. What you find interesting probably touches stuff you've had experience with, but just because you've done work on say, customized implementations of binary search, doesn't mean it's a good baseline for all developers everywhere. Maybe they've worked on different domains or solved different problems and can't relate to questions you personally find "interesting".

It'd be much fairer to select a boring question that involves standard stuff that everyone has to face at some point in their careers, like string manipulation. And even then, it just involve normal transformations ('look for and remove special characters') and not wacky, HackerRank-style rules ('no two bs after cs but before as').


I mostly agree with this approach. I think that you absolutely should be measuring the "boring stuff" because that's 90% of the work by number of hours spent.

On the other hand, I think there needs to be some proxy for "how well does the interviewee navigate complexity?" Because a programmer who does it well is far more valuable than a programmer who doesn't, and there's high variance on this between programmers and between fields of expertise.

The systems design interview sort of gets at it, and whiteboard interviewing often tries to get at it. I feel like I've yet to settle on an approach I'm happy with.


> Whiteboard coding interviews are one thing that I have to go out of my way to practice for and get better at over time when interviewing (ie over the course of a few failed interviews). I don’t feel more skilled or smarter by the end of the set of interviews, but I inevitably do better at these kinds of problems.

You have a good point, I noticed this about myself as well. However, I don't think whiteboard interviews are special in that regard. I noticed that I got noticeably better at the "sit down and code me a simple web API endpoint" interview, and I got noticeably better at the systems design interview, and so on.

I do think that whiteboard interviews tend to lean very algorithm-heavy, which doesn't reflect the role's actual day to day. And practicing algorithm interviews really does feel like an inefficient use of time unless your role truly demands algorithmic proficiency (like if you're a graphics dev).


in a sense, I agree. this is a signal to the candidate that the interviewers do not fully understand what they are measuring.

which also means the team might consist of people selected by using this metric. this is a good signal ;-)


> How is prowess in a game of "gotcha" an important indicator of engineering skill?

It's not; I couldn't agree more.

In real life when using engineering "skill", not only am I not anxious/stressed by trying to write on a whiteboard, but I'm using my laptop, with my editor, as well as access to man pages, docs, and google to look things up.

In addition to the overemphasis of performance responses, I think "how much do you know from memory with 10 seconds of thinking" vs "how much do you know with 10 seconds of google" is useless. The only fairly complex datastructures I can perfectly describe from memory are the ones which I used most recently...


"Gotcha" is about being adversarial. An adversarial attitude and a high-pressure situation are different concepts entirely.

> What if you consider part of someone's job to be communicating concepts to people, possibly with the help of visual aids and diagrams?

Perhaps it would be more effective to have the candidate whiteboard a concept that they are already familiar with, be it a high-level engineering principle or a system/solution they have built in the past. Attempting to solve a problem you have just been presented with AND communicating the solution effectively is a big ask.


That's an excellent idea. I'm in no way saying the existing method is perfect. Just that some of the things it tests around communication and being put on the spot and analyzing a problem in a way that is understandable to the rest of the room is actually a really good engineering skill. There can be other great ways to measure those skills.

I know my opinion is unpopular, but I sometimes do think I've figured out something other people miss. I think when it comes to whiteboard inteviews, candidates are often playing the wrong game. They think it's about gotcha questions and they think they fail because they didn't leetcode hard enough. I don't think that's true, they are just trying to game the thing that's easy to measure.

In my experience with the "terrible" FANG companies, it's not about gotcha questions. I get the offers even though I don't often find a non-naive solution. The people I'm in the room with really do want to see my thought process and they really do want me to communicate the tradeoffs with them. People don't fail the gotcha questions because they don't know trivia or because they forgot a detail from their CS classes. They fail the whiteboard interview because they see an unfamiliar question and say: "I don't know that trivia" instead of drawing out possible solutions and having a conversation with their interviewers.


They think it's about gotcha questions and they think they fail because they didn't leetcode hard enough.

But ... if you read some of the feedback from interviewers at "those companies" that rely on these interviews, they say the reason they failed someone is exactly because they "didn't leetcode hard enough". It is manifested as:

"Well other candidates got the same solution as you, they just did it 10 minutes faster"

or

"You missed an edge case, even though your core algorithm was correct".

This is a huge issue with these interviews. It's all too easy for interviewers to evaluate candidates based on how fast, correct, neat or "complete" you answer was. It's easy and takes no time.


Agreed, thats a disingenuous point. "It's not about getting the right answer but the way you think". I've never found that to be true. If you don't get to the right answer, you're gone. If they planned to ask two questions and you only got through one, you're gone no matter how you "thought" about it. A huge part of this is Leetcode practice. If you can't solve most algorithm questions on whiteboard in less than an hour (because you haven't practiced) then you won't pass any interviews.

> "You missed an edge case, even though your core algorithm was correct".

That may have been a reason why I have failed some interviews but I feel like most interviewers are actually good about this and will say something along the lines of "what about this input?" where my code does not work and then I have that "oh shit, that won't work for that" and then I fix it.


Thanks for elaborating so well on your initial premise, I think you bring up some good points about how this kind of interactive problem-solving can be an effective tool available to the interviewer. For better and/or worse, there's a reason why it's so prevalent now and controversial.

I'm inclined to describe it as a sort of interrogation technique, you're offering a stimulus (the problem) and aggregating a number of reactions to form an opinion, and open up new lines of questioning. Very delicate work.

I think problems arise when unskilled interviewers present an excessively obtuse problem to the candidate, then read far too much into their responses (this approach is also easily "hacked" by those who've memorised common problems of this ilk). To stick with my interrogation analogy, it's the equivalent of screaming in the suspect's face, noticing that they gulp before shifting in their seat and scratching their face, then deciding that "they must be lying".


That's an awesome idea -- as someone who rabidly hates whiteboard interviews, to the extent that I'm looking at the responses in this article as a note of who to consider applying with next, I would love the challenge of "explain a complex concept you're already familiar with". I've never gotten that in an interview before.

I try to start there, but most candidates act shockingly uninterested in going into details of their past work. I've directly asked about what the interesting parts of a project were to them and gotten things like "I had to learn ES6 and I hadn't used much JS recently" without much elaboration able to be teased out.

If you can't give me good examples from your past, I'm going to throw my own questions at you. I tend not to do coding on the whiteboard, though. Lots more boxes and lines and schema and system interaction-y stuff.


even then, this is not what's being tested with the whiteboard.

thinking and presenting are two separate skills, and, in my opinion, can rarely be executed at the same time.


So if you're looking for someone who can execute both at the same time, whiteboard coding is ok?

If your looking for someone who can think, code and present at the same time, yes.

Coding on a whiteboard while being questioned by two or more interviewers isn’t really a true representation of a work situation. It’s always more stressful and some people thrive on it, some people don’t. Im not sure what the better alternative is to demonstrate verba/technical communication skills however. The problem is, it’s hard to figure out if someone is a good fit with just a couple of hours of vigorous questioning. Maybe that’s the problem. I’d say I’ve worked with plenty of colleagues where it took me weeks or months to fully appreciate how extremely valuable they are to the team.

I agree with the sentiment but find most of my whiteboard time concerned with a much higher level type of problem solving than writing lines of code or absolutely correct algorithms. I also mostly do it with colleagues I know on shared problems we are working cooperatively to solve. Where I’m using one with strangers I’m much more often working as an expert in an explanatory manner. It feels quite remote to my experience of solving an unknown problem in an interview situation.

Yes!

What you're testing is the ability to discuss a problem with your peers. That is the critical thing.

Do the whiteboard but don't make the coding the standard. Don't get too hung up on the details of the problem.

Make the problem easy but fuzzily specified.


VPE at Eaze here -

Clear and respectful communication is one of the most important skills for an engineer to have.

If you read the second half of my answer in the article I go into the communication side of things. In my experience there are better ways to evaluate a candidate's emotional intelligence and social skills than asking them to code in front of someone.


I'd say you should stick to your guns - I like your approach. Interviews are inherently adversarial: "are you good enough for us to hire you?", "are you better than the other 5-10-1000 candidates". As a result there's a built-in bias which makes whiteboarding a bad fit.

I've written code on white boards at work, and I've discussed about code on white board with colleagues or managers. It's not the same thing as during interviews. The schedule is never as tight, scrutiny is way laxer and the overall mood is completely different when I'm working with colleagues or even bosses.

I kind of understand why the BigCo's do it (they need a super rigid filter since they have so many candidates), but in their case they could select for people with the best pink leotard on interview day and they'd still get decent programmers, because their companies are in such high demand and they generally already control their markets (software, natural monopolies, etc.) and can afford to pay a ton so the competition would be cutthroat anyway.


>> What if you consider part of someone's job to be communicating concepts to people, possibly with the help of visual aids and diagrams?

In that case I would recommend reading the candidate's resume beforehand, look for prior experience publishing, presenting, or teaching and ask them about it.


I agree, and as an employer I find a happy medium is to test on a whiteboard, but be completely okay writing filler, a comment saying "code for this goes here", etc. So long as they're building the correct general approach, that's all I need to see.

Whiteboard interviews where the interviewer says "it's actually `.toLowerCase()`, not `.lowerCase()`, you fool!", or "oops! You forgot to `position: relative;` the containing element that you `position: absolute;`d below!". you're not testing anything useful. Maybe if we were still coding everything on punchcards and using massive user manuals, but docking applicants for things their editor would highlight or one ctrl-r on the page would find is ridiculous.


Never seen anyone write code on a whiteboard at work.

Do write lots of sequence diagrams, block diagrams, ui sketches, arch diagrams and very occasionally someone might draw a data structure.


This. Plus network diagrams, message passing sequences, and first drafts of checklists.

I think now a days, selection through the whiteboard process simply comes first to how much you grind leet code and the like.

Ironically this leads to min- maxxers who ignore a good chunk of their courses simply to master leetcode. My smartest peers are ones who work on interesting projects and research, thus never finding time to grind interview questions.

Then there are also companies that expect your white board code to compile and have perfect syntax, which imo is very unreasonable.


What if you consider part of someone's job to be communicating concepts to people, possibly with the help of visual aids and diagrams?

This is incredibly common, and you tell the candidate in advance that they will be expected to give an n-minute presentation on a subject of their choosing (need not even be tech) so they can prepare.

Tell me this: when did a mob last ambush you at your desk and demand that you invert a red-black tree on a whiteboard that they happen to have with them right now? I'm guessing that never happens where you work. If it does then fair enough :-)


I don’t think there’s much criticism of those types of whiteboard interviews. I’ve had programmer interviews that involved sketching out a system architecture or database scheme on a whiteboard, which I think is perfectly reasonable.

It's one thing to do it with colleagues for whom you have rapport and the risk of saying something wrong is low. It's a different thing when doing it around total strangers and a new job is on the line.

How about testing architecture (and implicitly communication) in front of a whiteboard and programming behind a keyboard?

VPE at Eaze here (the original author of the quote above) -

You're 100% correct. We give our candidates the choice between working through a problem at the office (on the spot as you say) or doing a take home project asynchronously. Not everyone has the time to do homework, but not everyone wants to do an in person coding interview either. We try to stay flexible.


Thank you for the response. I appreciated your take on the situation in the original article and I am glad to hear that you accommodate developers like me that don’t perform well for strangers on the spot. This type of thing really pushes a company up the ranks if I’m interviewing with them.

That's great to hear. I love getting feedback about this stuff, positive or negative! We're constantly evolving our process.

I think this is a great approach. It keeps the company flexible to hire a broad array of talent under differing circumstances while also letting the interviewee play to their strengths.

How do you compare the resulting apples & oranges? I can do a lot more at home (especially if I cheat on time, which everyone who really wants your job and can afford to do will do)

We're less concerned with the resulting code than we are about your ability to explain the code that you wrote and your ability to prove to us that you have good judgement when making technical decisions.

Also, we're growing fast enough that we're rarely comparing candidates. If we can hire both the apple and the orange (assuming both candidates are evaluated to be good for the role), we will.


I'm actively looking/interviewing and really like the "cut of your jib". (both your answers here, plenty of aspects of Eaze as a company, the prospect of moving back to SF...)

For both the sr backend and devops positions, how important to the roles is familiarity/experience with your technical stack? I might have some of the skill set/experience you're looking for -- sr backend engineer, sr systems engineer, devops are all positions I've held -- but honestly I don't know JS, .NET, or Chef. Bluntly, I don't want to waste your (or my) time. ;)

<tiny>Also, I wish HN supported private replies</>


Do you want to work for PlayStation Network team? We have plenty of open positions from DevOps to server or client side developers. And variety of work also there - commerce, social, video streaming, distributes databases, big data, ml.

You name it, we are doing it.


Maybe? Sounds cool! Can you send me a very very short email (my email is on my HN profile page) as a point of contact for further communication?

We care less about your particular technical skills than we do about your generalized engineering skills. Specific stacks are easy to teach; fundamentals, emotional intelligence, and social skills are harder to teach.

In fact, if someone is too into their stack, we see that as a bad sign.

So I'd be super excited if you decided to apply :)


I'll submit a resume and a CV sometime late next week. :)

Minor kvetch: quoting the way you did it makes long lines very difficult to read. I usually quote like this:

> I am a quote

This makes the quotation doubly-distinct, and still readable on mobile devices.

===

To the actual point I wanted to make: plenty of engineers at companies code on a whiteboard. They schedule a meeting, grab a room, and talk things out, while making notes, diagrams and sometimes even actually writing out some code on a whiteboard.

I hope nobody asks people to write compilable code on a whiteboard, but asking a person to talk through a problem and jot down some pseudocode doesn't seem like an awful thing to me. Communication is a pretty critical part of our job.


“Jotting down some code on a whiteboard” with a colleague is a much lower stress scenario than deriving and writing down, under a time limit, some DP algorithm you might not have used since college, and proving its correctness and run time to some stranger who may be barely out of college themselves.

I don't think people should play CS-quizshow during whiteboard interviews. Being asked to implement a breadth-first search, or whatever, is kind of annoying - especially since there's effectively one correct answer. At best, you're testing my memory and whether I read the right interview book.

I had to do that at my last interview. I got through it ok-ish. The more interesting question was a more general system design question - how would I architect a system to do X, under constraints Y and Z. What would I do if a new constraint came up? Ok, now how would I make it more resilient? There, the whiteboards is just a tool I can use, not the primary focus.


Surely not BFS. That's something you can figure out from first principles and knowledge of some data structures like stacks and queues, but I'd expect knowledge of those data structures anyway.

Sure, I can, and I did, although I didn't come up with the super-hindsight-obvious solution I'm sure I learned three times over in college.

But it's the interview equivalent of your driving instructor making sure you adjust your side and rear view mirrors before you start the car.


I don’t care if candidates can figure out BFS under intense pressure in 30-60 minutes. That is nobody’s job anywhere ever. I want to know if someone can think creatively, if they’re a pain in the ass to work with, if they’re thoughtful and careful or if they shoot from the hip. Admittedly, these are hard to measure (which is one reason why I would support some kind of mild licensure, but that’s a different subject), but being able to derive BFS does not correlate with competence or ability. Maybe if you’re doing router hacking or something, I guess, but specific algorithms are so little of most developers’ careers.

Honestly, we all might as well read chicken entrails because that would be about as predictive as our current interview practices.


You’d be amazed at how little some otherwise competent people can figure out from first principles in an interview in front of a whiteboard.

Interviews are necessarily more stressful than typical work. That's not just a property of whiteboard coding.

More stressful, sure. For many people, whiteboard coding is disproportionately more stressful than typical work, and that’s the problem.

One particular expectation when whiteboard coding for an interview is that there is little/no downtime, you must be making progress or talking about your thoughts. Incidentally, 50% of my thought process then becomes "How do I talk about what I'm thinking about? Oh no, I'm only thinking about talking about what I'm thinking about..."

I'm working on a large-ish project right now, and into one of the more tricky bits literally today. And you know what? I take breaks. I go read something on the internet or post a comment, or I go for a walk, or I go do one of the smaller housekeeping tickets I keep in my queue to give my brain a rest from continually focusing on the hard parts of the problem.

Can't do that in a whiteboard session.


Most of the time their technology stack with be vastly different than anything else you've worked with. There will be other people you will need to discuss and coordinate with. Articulating your thoughts and expressing yourself clearly and concisely is more important.

Vast majority of the technical problems have been solved and its delivery a solution to a business problem that is the most important aspect.


For this reason I don't do living coding sessions. People have asked me `why` which I politely say the answer is no. They seem to like the boundaries I set for myself and my project's more than some sort of white board.

Yes, I've been turned down for jobs over the white board but I've had more positive results than negative.


"Interviews are necessarily more stressful than typical work. That's not just a property of whiteboard coding."

My sister, a pediatric ER nurse would disagree with you. The interviews are largely behavioral and are a breeze. No dummy is wheeled in with head trauma, random "new" diseases aren't invented and asked to be treated, etc. The simple fact of the matter is if hospitals hired in the same way, they would have no staff.


I would argue that a piece of paper showing that someone attended school and graduated and is licensed to be an ER nurse carries much more weight than a piece of paper showing that I'm allegedly qualified to be a software engineer.

I know it's totally anecdotal, but we've all heard horror stories about candidates who couldn't write a for loop; some of us have witnessed these things first hand. And yes, phone screens should be filtering out those sorts of candidates long before they start sweating with a dry-erase marker in their hand, but, well.

How likely is an applicant for a nursing job to flat out not know how to stitch up a wound, or to take a patient's pulse and temperature?


Again, the op stated these things are put there to "show how people react to stress" -- my post was a response to that, there is no re-creation of a stressful environment in the situations I stated.

"I know it's totally anecdotal, but we've all heard horror stories about candidates who couldn't write a for loop; some of us have witnessed these things first hand. And yes, phone screens should be filtering out those sorts of candidates long before they start sweating with a dry-erase marker in their hand, but, well."

Yes, it is a failure of how you have set up your hiring pipeline which you are now band-aiding. The majority of those folks can be screened by one look at a resume or in the first 30 seconds of the phone interview. Other hiring managers in our company repeatedly had this problem until we got them to focus of the right candidate qualities and ask the appropriate questions.

Take for example your local symphony orchestra; they have the same problem where people with visions of "making it" show up not being able to play at all. Want to audition? Send us an audition tape and a check. When you show up for the audition, you'll play a selection from these pieces and be asked to sight read this music. It is ironic that for an industry that is in a sense so subjective that the gates in the hiring process are more concrete.

To make an analogy, the software world is akin to:

Interviewer: "I see you are interviewing for the 1rst chair violin. The 3rd chair tuba player is really into experimental music, he would like to transpose Vivaldi's Four Seasons into a new scale with 12.5 notes per octave with a slight progressive jazz leaning. Oh, and since we all know there is pressure in performing in front of an audience, you have 30 seconds to think before the 2nd chair begins to throw rotten food at you. Reaction to stress and all you know...here is your tuba."

"But I don't play tuba...Are you asking me to play tuba? Am I going to be playing this nutcase's new music as part of our program?"

"Sigh...you don't know music do you?"


The analogy to white-board interviews for hiring a musician is:

"Here's a couple of pages of unfamiliar sheet music that a second-year student should be able to play. You have an hour to figure out how to muddle through it on an instrument of your choice."

People hiring musicians don't do that, because they instead prefer to give candidates 16 bars of complex sheet music, and expect them to play it perfectly during the audition.

The programming equivalent would be to give someone a hard take-home problem, let them stew on it, bring them into the interview, and ask them to type in their solution, from memory, into a text file, on a keyboard with a broken Backspace key. That they will then compile, run, and compare the result of to that of the other 60 candidates auditioning for the role.

Are you sure you want to do auditions, instead of interviews?

> It is ironic that for an industry that is in a sense so subjective that the gates in the hiring process are more concrete.

That's because there's fifty thousand correct ways to solve a trivial programming problem, but only 'one' way to correctly play second violin in Vivaldi Four Seasons.

Music is a subjective art. Playing music is a mechanical process. My iPod can play music. My iPod can't implement a sorting algorithm.


> The majority of those folks can be screened by one look at a resume

Not a significant enough majority, imo.


That's because she's already went through all that stress and bullshit and skills testing in med school and residency. If any clown could call themselves a nurse, and would apply to ER nurse jobs, it would take all of ten seconds before nurses would have to do whiteboard triage interviews.

I have no idea what the candidate did in their CS undergrad. Maybe they cribbed all their work from their roommate. Maybe they went to a party school. Maybe they spent the last 4 years as a 'Senior Developer' at FooCorp copying files from hard drives to floppy disks, and posting a few paragraphs a day on the company's WordPress install. Maybe they are an Architecture Astronaut who can talk for six hours about how great Haskell is at doing multi-manifold monadic trivariable entaglement, but has no idea how to do any real work.

Or maybe they spent the last decade building Bigtable and MapReduce, and Spanner, and TensorFlow at Google. I'm not an expert on Bigtable, or MapReduce, or Spanner, or TensorFlow, though - and I can't definitively, in 60 minutes, tell if the person I'm talking to is bullshitting me. I can't tell if they actually did any of that work, or they coasted. I can't tell if the complicated problem they are describing to me is actually hard, or if they are embellishing it. Even if I felt confident that I could make that conclusion, my opinion would be incredibly colored by personal biases.

Oh, I should check their GitHub, you say? Well, guess what - Jeff Dean - the guy who did spend the last decade building Bigtable and Mapreduce, and Spanner, and TensorFlow - doesn't have a GitHub account. Presumably because he has better things to do with his free time, then work on OSS.

Oh, I should hire fast and fire fast? Don't get me started on why that doesn't work...


At least a test of triage skills would be a real world skills test. The equivalent for most whiteboard software engineer interviews would be a quiz on cellular biology.

Hospitals also hire people who went already through an even more rigorous screening process than even exists in our field just to become eligible to be nurses and doctors.

Once you're an RN or an MD with all the appropriate qualifications, assuming you're not outright faking them, they can be reasonably confident that you are, in fact, a competent nurse or physician and move on from there.

We don't have that, and so we have to spend a lot of time making sure that a prospective candidate even has the basic skills and qualifications of a software engineer.


As an embedded systems engineer, I disagree. I have never been asked to design a circuit, or even pseudocode firmware, on a whiteboard. In the electronics manufacturing industry, interviews consist of talking, mostly about projects I've worked on before and projects they've done before. Occasionally someone will give me the same written test they give technicians, but those tend to be pretty easy.

> some DP algorithm you might not have used since college, and proving its correctness and run time to some stranger who may be barely out of college themselves.

I'm not opposed to white-boarding, but to reinforce this point I'll note that I would have done much better on some of these problems when I was just out of college than I would today, because they were all fresh in my mind.

I assure you I wasn't a better programmer or employee then.


"Whiteboard interview" typically does not mean "sketch a general design of a system", or the other things whiteboards get actually used for on the job. It means "here's an algorithm challenge, solve it by writing the code on the whiteboard, and we'll flunk you if you make any mistakes".

Not always a whiteboard, either; one of the best engineers I ever knew flunked a Google interview because of a situation where he had to write a bash script and read it over the phone to the interviewer, who apparently didn't transcribe it correctly on the other end. But "they only hire the best", you know, and their practices are rock-solid and proven.


Oof, I've had that experience during a technical phone screen with a different "hires only the best" company. I was asked to write (over the phone) a trivial statistical algorithm and started to describe the algorithm: "Function F returns a double and has two parameters, pointer to the start of the double array P and integer N for length of array." Apparently on the other end of the line was a human compiler that kept rejecting my input and preferred "double F open parens double star P comma int n close parens"!

This is hilarious! Such a strong indicator that you, as a candidate, should reject the employer.

Yes, it was the final straw and led to me rejecting that industry as a whole :)

What are you doing now?


Hah! I love the AXBY code-entering minigame :P This is pretty neat so far.

I, too, have a side project I'd love to quit my job to work on, but I think it's less monetizable than an actual game.


Thanks! I really enjoy coming up with the themed minigames. The next one planned is a Kanban board minigame ... think of a cross between Tetris and the boardgame Patchwork.

Ha! I did that for a year...and thinking about doing it again. I mean, selling my home and moving to say, costa rica, i could stretch my dollar, dev my heart out, and watch all the sunsets my heart desires

I've worked at quite a lot of companies. Many of us will, occasionally, grab a room / whiteboard to go over something but 99% of the time it's a sort of flow or UX type thing.

I've _never_ seen someone, or have asked to participate in, some sort of whiteboard coding thing. Even with pseudo code. That just doesn't seem helpful to me, at all.


Agreed; when there is code talking, we share screen on a projector/flatscreen and do it that way. How is writing code on a whiteboard good for anyone? Cumbersome and not reusable.

I don't doubt lots of companies do this, but I skeptical about the coding on a whiteboard. They talk in person, sketch out diagrams, highlight important aspects - why? because these things are all easier on a fluid analog medium like a whiteboard or piece of paper.

Actual Code? Not a chance. Portability, Durability, Efficiency - It's the worst of all worlds.


Thank you for the quote pointed. I will remember that for next time! As to you’re point, I think others have covered it well, but I will add my agreement that communicating in an environment where you are comfortable and familiar with the topics ahead of time and won’t have your career prospects put in the line is much easier. Some people like myself simply can’t prepare for an infinite number of possible whiteboard scenarios and look competent.

I've aced every whiteboarding interview when the problem was the same or similar to some problem I solved before, and I failed pretty much every interview when the problem was new to me (except when the problem was trivial, ala fizzbuzz). I think that proves how whiteboarding just tests whiteboarding skills and nothing else.

A team I was on at Google (XLA, the compiler for TPUs) used whiteboards almost daily to express algorithms to each other. Definitely helpful for us, but I can see that just being a single team's dynamic.

No comment on it being an effective interview process.


Really? I have multiple in person discussions per week about how we are going to tackle some problem where everyone chips in and those are just the weekly problems we are working towards. There are also the much larger design docs and while some of the feedback on those happens asynchronously, a lot also happens in real time during meeting reviews. Oh, and both of those problems are decently well covered by your standard interviews (the former generally being data structure/algorithm design, the latter generally being system design).

It's funny, when I saw the title I immediately thought "Hell yeah, whiteboard interviews are absolutely necessary". As I read the article, I realized it meant actually making people code on whiteboards, which is absurd. I've always used whiteboards for high level design and architecture questions, and there mostly to aid the candidate in organizing their thoughts. If I want to see someone's code, I'll ask them to provide a code sample.

I guess it depends on the job, but for outage response, being able to understand a problem, and update or write new code in a reasonable amount of time is kind of a useful skill. Discussing it on a board with others can be useful, if the code isn't complex. Of course, that also depends on the environment; if you're in an environment can't actually push any code, even emergency fixes, quickly, then it doesn't help a lot.

Do you design clever search algorithms during outages?

If the existing search algorithm is the cause of the outage, maybe. If I a clever search algorithm will help me filter the data so I can reduce the scope of the outage, yes.

Are there no existing tools to search through data?

Everything is already implemented, let's close the patent office.

When's the next 50% off sale?

There's some logic to that. It's the one of the same reasons we have high stakes exams in school: to show what the individual can do under pressure. In an interview setting you can't simulate what it's like to be at the end of a high-intensity sprint, but you can ask the candidate to answer a tough question on a whiteboard and (ideally) get a notion of how they work when the going gets tough.

As a former air traffic controller and now data scientist, nothing in this career field is ever done under any real pressure.

tremendous respect to air traffic controllers. i cannot imagine the level of professionalism and responsibility these people must have! no amount of monetary compensation is enough, in my opinion.

Thanks. While everything you said is true, its also a hell of rush. Hardest part of changing careers ... no rush with a daily dose of dopamine.

But what about that one time on Swordfish!? /s

The pressure of a whiteboard interview has nothing in common with the pressure of a short deadline. It's like testing people for Tour de France by putting them on a unicycle.

Now there's a prologue I'd actually watch.

And what is it measuring exactly? In real life you don’t get the score. You either did it or not. Nobody cares about how you did it, only answer matters.

And interviews are not pressuring, they are simple. No hard desisions, no anxiety whether it is going to work. You in and 5 hours later you out. Lame.


unless the job requires whiteboard coding, you are not testing for the job.

an advice to candidate: when you've been asked to do whiteboard coding - run away. this is a negative signal.


All of these interviewing "tools" (or tricks) attempt to be time/cost efficient proxies for doing the damn job, and they all suck.

* Whiteboard coding is awesome for software development shops that don't actually own computers or use punch cards to load programs.

* Shared coding environments with a time limit works well when you want to double screen for someone who can also diffuse suspicious packages that arrive at the office

* Riddles and puzzles are good when your workplace has a chicken coop, an office fox and you can't figure out how everyone can go for lunch without leaving the fox alone.

* Behavioral interviews are appreciated by candidates who took Psychology 100 back in school for an easy A.

* Take-home tests go over well with the huge population of talented software developers who can't find a job and have loads of time they want to spend decoding the operational cost of a bubble sort

The only thing I've seen that's at all realistic and effective is a very short, __paid__ project. I did a two-day one for Indeed (ironically one of the worst promoters of all this bullshit) and a 4-hour one for my current employer. The payment doesn't even have to be market, it's more important as a signal to candidates that the company values your time.

I ask for 3 things from perspective employers:

1. value my time like you value your own (both the number and composition of your interview steps)

2. keep me updated as to where we're at in the process and when the next stage/decision will be made

3. Move forward in the process in a timely manner. It should not take more than 2 weeks from when you initially contact me to the process concludes.

I've never gotten more than two of the above from a single organization, but I will someday, and I'm betting that a company that treats potential employees that well will treat actual employees better as well.


Riddles are the worst, I was recently asked the "You have a 5 litre and a 3 litre container, how do you get 4 litres" question (never heard it before).

It's so simple to figure out if you're on your own and just play around with the idea. When asked on the spot I just kept thinking "hey these people want an answer NOW, don't make them wait" while feeling their stare, and couldn't figure it out without help.


I have found the best course is to treat the interview as a situation where a colleague has come to me with a problem that we are hashing out together. I feel a lot less pressure with that mindset, though I do get thrown off by interviewers who take an adversarial approach. But I find this an acceptable loss.

I guess if you are old enough you'll know that one from the movie. Doesn't mean you remember how they solved it (because what did I care at the time?). Nothing to do with programming unless someone asks you to write a short program to figure out the most efficient (least steps) on how to do it. Behind a computer.

Yup. Bruce Willis and Samuel Jackson were able to figure that one out. It can't be that hard. They were under a lot of pressure as well.

{

t0:{[3,5],[0,0]},

t1:{[3,5],[0,5]},

t2:{[3,5],[3,2]},

t3:{[3,5],[0,2]},

t4:{[3,5],[2,0]},

t5:{[3,5],[2,5]},

t6:{[3,5],[3,4]},

}

Thinking about making this an algorithm, are we forced to use recursion?


I agree with much of what you say, heck, nearly all of it -- but it's not reasonable to expect, or even ask for a _very_ short paid project. I see no reason that a possible employer should pay actual money for some useless task.

If it's very short, then almost by definition it's useless.

That being said I've had great results from doing, say, a tiny consulting project, and ending up with full time employment. The best jobs of my life have followed the pattern of "am either offered, or I manage to ask/negotiate for a small consulting project" -> "before the project actually ends, am brought on full time".


> I see no reason that a possible employer should pay actual money for some useless task.

My time is valuable. I see no reason to work on a useless task for free.


So is their time. Takes candidate time to do, takes employer time to test/evaluate. Both parties are risking wasted time. You're wasting time driving to interviews and answering calls etc etc. Its the cost of doing business.

Asking someone to spend an hour on something is not a big deal, but I've seen/heard of stuff where they're talking about half a day or even an entire day. For someone with other things going on like a family (I know it may seem outlandish to younger readers here, but it does happen) and a current job, that's asking an awful lot. It does not take the company an entire day to review that exercise, making the time commitment very asymmetric.

How did you follow "take-home tests suck" with "two day paid projects are great"? Sure you're at least compensated for your time but most employment agreements almost certainly block this (unless you're a contractor), and that's assuming I'm willing to use 2 vacation days to maybe get an offer.

Following your style of writing:

* Paid projects are appreciated by candidates who are currently unemployed.


The issue with a paid project is you can't legally do it with people on work visas, which is a large part of your interview pool.

They are all imperfect proxies due to various constraints.


What? Just let the programmer to it in his homeland. Easy. Just as outsourcing.

I wish this project approuch was more common. It would probably be cheaper than wasting time on multiple days interviewing reality shows where people are voted out one by one like some companies do it.


It doesn't work when they are already working in the foreign country. They aren't going to travel 12 hours to do a homework assignment for you legally.

A regular viewer of my daily Twitch programming stream (link is in my profile) asked me to solve a problem he was asked to whiteboard. He wasn't asked to draw diagrams or write pseudo-code so they could learn how well he communicated. He was asked to write the code and it was heavily implied that it must compile and run -- even though whiteboards don't do that.

Here's my attempt: https://youtu.be/6LHqrxrC6Uo

I solved the problem, with an IDE and a compiler. I communicate during the entire exercise. It takes me over 2 hours. Granted, I debug it, so that takes extra time. (Can't debug on a whiteboard!) I had to take one break. On top of this, I've solved this kind of problem before and it still took me more than the 45 minutes you're likely to get in a whiteboard interview.

And I try to cover all of the "hot topic" points I know the interviewer is thinking about: size .vs. time tradeoffs, iterative .vs. recursive, etc.

If I had to solve this problem on a whiteboard, in 45-60 minutes, with the bar being "it must run"....I would fail.

I guess that makes me a poor programmer. Instead, I'm a grumpy old man who is really tired of all this fraternity hazing bullshit.


I feel like you're vastly overcomplicating the whole thing. Granted, I don't know if there were any parameters specified other than "Find the largest connected segment in a 2D grid".

I had to solve almost the exact same problem very recently. I find the best way to start is to just implement the easiest solution you can think of, such as the array approach you mentioned in the beginning. I did that in 5 - 10 minutes. We spent the rest of the interview optimizing and fleshing out the problem (e.g. let's not use an array, but there is only one "color").

Overthinking the problem straight from the beginning and potentially being unable to provide a working solution at all is probably the worst thing you can do. I actually had that happen in a previous stage of the aforemention interview, and had to "reset" by going back and implementing the simple solution before optimizing it.


Kudos on being able to "reset"! That's probably the hardest part, fighting against the sunk cost of a snowballing probably wrong answer when you have such limited time.

I got an impression that just specifying the input data took almost 1.5 hours, because of C++ and a decision to have it as a graph, not as a matrix. If an interview is in Python, one would write something like ``grid = [[1,0,0], [1,2,0], [0,2,2]]``, and be done with that part.

Probably you got exhausted after doing all these preparations and debugging issues not related directly to the algorithm. I'm not sure the final solution is correct, it is not tested on a graph with multiple connected segments of the same color. It looks more like a convoluted way to count colors globally, discarding standalone colors, if I understood your solution properly.


Thats the fun part 'to me' about mastery of cpp.

Sure you COULD use a graph, but using a different code abstraction to represent the idea of a graph is much more pragmattic and maintainable, of course that varies with application.

Im reentering interviewing phase right now, and its funny revisiting these problems with a new lense. The mind is very plastic and its exciting, so far as things to come.

Total nerd out moment :v


``vector<vector<int>> grid{{1,1,0},{1,2,0},{0,2,2}};`` in C++

I think it's trivial to code an optimal solution (and discuss tradeoffs) in 45 minutes on a whiteboard. It's just BFS or DFS.

Of course most people prefer to interview in a language which is less verbose than C++, which saves time.


Perhaps it is trivial, but what's the point? If you can reason what algo to use and reason how to determine which one will be the most efficient of the two without testing them both (or explain the abstraction which allows you to test them both without significant overhead in code), it should be enough.

In theory there should be no difference between theory and practice, but in practice there is.

That doesnt follow to me. In theory, there is a difderence between theory and practice, because theory simplifies reality into a model with given assumotions, and reality...is reality.

Unless of course you have the infinity gauntlet


Obviously, I didn't mean that. Just from a white boarding perspective, that should be enough. Give the applicant a computer and have her implement it.

I skipped around on the video. You'd literally have 1/4 the code if you just coded a graph correctly.

You also keep a "counted" and "visited" variable separately for no reason. There is no reason to visit a node and not count it, and you can't count a node you didn't visit. Whatever optimization you think you are getting surely isn't worth it.


It makes you someone that can't listen. The most important part of communication is listening. When the interviewer asks you to whiteboard a problem, they aren't asking you to "solve it". Obviously, you only have a whiteboard and you only have 15 minutes max. You might throw out some comment about size vs. time (eg) but make the decision and move on, quickly. The interviewer might decide to latch on but if not, you have to cover this in 15 minutes so you limit the depth so as to do that. Stub out all the deep functionality and then dig into each part of it as time permits and as the interviewer leads you in those directions.

As an experienced and good programmer candidate, the most important part of an interview is for you to evaluate the company. So the whiteboard is a great way to see if they understand what can be accomplished in 15 minutes on the whiteboard.

If they don't get it, you can end the interview short. Time saved today as well as the next several years working for a shite company.

I love the whiteboard interview.


At what point did I ever imply I don't listen?

I explicitly described the conditions of the original interview. The interviewer asked the candidate to "solve it" and it had to run. What part of that wasn't clear?

I also find it interesting that you countered with a completely different kind of whiteboard scenario. I agree that the scenario you describe is fine. I would enjoy those kinds of interviews all day and twice on Sunday. I'm not railing against an honest discussion with a potential employer. But that's not what happens most of the time, in my experience.

Also, the tone of your reply is that you reject the employer if they don't meet your definition of reasonable. That's great, but not everyone has that luxury.


The scenario nybblesio describes ("asked to write the code" with expectation it would be able to run) is not the one you described ("they aren't asking you to "solve it").

I think an under-tested aspect of software engineering is the ability to research solutions on the internet.

Just give people a search bar and ask them to solve a problem outside their comfort zone. See what terms they use and how quickly they can arrive at a useful link. No pseudo-code or architectural diagrams needed. Just a link with a plausible solution. Because that's how most learning on the job actually happens.


I agree. I interviewed people who optimized for white boarding interviewed and, as such, could knock up CS algorithms which you can trivially import from libraries all I wanted. But when asking them a problem they did not encounter before and Google, they got very stuck. While, every time, there was a way of writing the query to Google that had the answer in the top 3 (usually #1). People waste crazy time on reinventing the wheel.

Anecdotal: we had some problem to solve which required qua a lot of code to solve and only old sites with broken links came up in Google for the guy solving it so he decided to implement it himself. When I asked why that task was taking so long he showed me what he was implementing. The code he was writing had an implementation on an old site which had a broken link to the code; when I copied the name of the zip file that was linked in github; there was the code. It had no description or comments; someone just checked it in. It was not perfect code, but it shaved off a few days of writing it from scratch anyway.

I care about being able to code, which can be assessed from past code and a pair programming session and then efficient problem solving using your brain and internet. The latter is somehow less common.

So my favorite way now is; I ask them to 'solve' a problem they have never encountered and that cannot physically be done during the interview time (I am interviewing for software development and in our field you get asked for things that cannot be done in the time you are asked to do it all the time, so I need to see how you handle that); give them time to Google possible ways to do it and present a little plan. Then they need to pick, out of the plan, something they think they can do inside the interview time (see how confident they are and if they have any sense about low hanging fruit or estimations; I might suggest something else if the task they pick is only installing libraries for an hour ;) and we'll sit together behind a monitor and do it together. I'll usually tell them to stop after 15-30 minutes as I have seen enough at that time.


I did an interview problem like this a while back (was about combining CIDR blocks) and I found an answer on the Internet. I coded up a similar solution (I used a slightly different data structure with a slight optimization just to show I didn't copy the algorithm exactly). The place actually complemented me on my Google foo as they claimed they asked the question because they knew (thought?) people couldn't look up the answer. Of course, they dinged me by saying my code had too many comments (nevermind I was detailing WHY and HOW my algorithm was different from the Google results). I didn't get any love for the man(1) page I made either. Oh well, can't please everyone. :-)

If I were interviewing that would absolutely be an important part of the interview. It never ceases to amaze me how bad some people are at searching.

Hell, I've coded in languages that I didn't even know (didn't really even know what the language was -- I think it was like VB or something) by copying terms from some sample, reference or other part of the code and putting in the term or idea I was looking for.

Additionally, just try to look up items on a language that is in (constant?) flux like Swift. Swift 1.x? 2.x? 3.x? 4.x? What's the API today -- naming convention changed, parameters changed, etc. All I can say is that thank goodness Google allows for date ranges with searches. :-)


Principal Engineer from huge gaming company here.

White board coding interview are testing only one thing: how well candidate is prepared for it. And here what is wrong with it: The assumption that candidate should spend his/her valuable time preparing for someone's assessment is arrogant. I do understand why Google and Facebook do it (the do other arrogant things), they assume you want to work for them so much you will study to make the cut. So, they track bunch of metrics, which makes THEIR life easier. They have baselines, calibrations, and other things you never have in the real life. Hilarious part is that they are both risk averse (better to not hire a good candidate than hire a bad one) and using brood-force approach (they will interview you endless number of time).

And if you are not prepared - you will most probably fail, unless you are really good at it or lucky. So, why should I prepare for Google's or someone's else interview? I have a interesting and very busy job, I just don't have time for this. I have commitments to my team to work on real products, not on fake problems from Cracking Google Coding Interview.

Just think how absurd it is?

So, starting from 6 month ago I: 1) Tell recruiters upfront I will not be spending a minute preparing for their interview process 2) I decline coding on the whiteboard. High level designs are fine, writing code - no, no exceptions 3) And the most important, I stopped asking candidates to code on the white board.

The most important skill of the software engineer is (IMO): ability to keep complex problems in context for long time (not 5 boxes and months), ability to manipulate them and ability to convince others that you idea is worth pursuing.


> So, why should I prepare for Google's or someone's else interview?

Because you want the job? Everyone is busy, that's a terrible excuse not to brush up on your interview skills.

By the tone of your post, my sense is that prior to your recent epiphany you weren't very kind to candidates who you interviewed.


Do I? There are a lot of great companies, why should I waste time on Google? Working there is not as fancy as you think.

>> Everyone is busy, that's a terrible excuse not to brush up on your interview skills. I believe that their approach is arrogant, they just don't value candidates time.

I have a confession to make, I spent some time at Google. And after I left I was interviewing people using their approach and I regret it now.

P/S/ When you interview for a company, you actually taking more risk that the company (talking about folks who are headhunted into interviews). If it doesn't work out, you will be out searching for a job, you career growth may be slowed down. And what is the company risk?


> Do I? There are a lot of great companies, why should I waste time on Google? Working there is not as fancy as you think.

I'm definitely confused. You don't want to waste time preparing for an interview, but you will waste time interviewing at a company for a job you don't want?

Yes, there are lots of companies hiring. But in my experience, in preparing for one software interview, you're preparing for others as well.

I interviewed at Dropbox, Amazon, Valve, and Indeed, within a span of a few weeks, and the prep work (Cracking the Coding Interview) was applicable to all.


What LaserToy is saying is that it's not just a little preparation; a few hours here and there. There are people who turn it into a literal hobby and do nothing else. If grinding through competitive programming questions is your idea of fun, then do it. Not everyone has interest in spending 2+ hours a day for a month to prepare.

That point I get, people may not enjoy prepping for an interview.

That's different than asking "Why should I prepare for a job?"

If you want the job, you'll put in the effort to prepare, regardless of your feelings on the process. That sacrifice (2 hours a day for a month) is minor in the grand scheme of things. Granted to the OP's point, Google probably isn't worth it. But that's a value decision each candidate has to make for themselves.

I'm preparing for my brown belt in Krav Maga. The test is 6 1/2 hour grueling physical exam that includes a comprehensive test of all the material from the previous 4 belts. Not only that, we're the first group eligible to test, so the instructor wants to set the standard with us.

Not everyone wants to put themselves through that hell. But those that do will put in the effort to be ready come test time.


>>The assumption that candidate should spend his/her valuable time preparing for someone's assessment is arrogant.

Plus, if some one has to 'prepare' for an interview that is supposed to test people's capabilities to do 'everyday' jobs, then you are hiring the wrongest possible people out there.


How do you interview candidates for your company?

Brute-force, not brood-force. Do you work for Blizzard? ;)

Having just been through this process (landed a new job after a 2-month search), the worst part about whiteboard coding is how humiliated you feel if you don't get it right or don't know where to start. Is it really necessary to do that to candidates?

I've been doing this for 15+ years professionally, have a master's in CS and I struggled to answer many questions. Just stood there blinking like a goldfish.

If companies really wanted to simulate programming work, you'd give me 10-30 minutes to Google the problem because THAT'S HOW IT WORKS IN REAL LIFE. Which is how it should be; rarely are you solving a new problem, usually other people have faced it before, it's probably far more efficient to start with a known working solution and iterate from there.

Look, of course there things you should know. Data structures, algorithm basics, some complexity theory, etc. But asking me to output numbers in a matrix in a spiral fashion does not translate into real-world ability.

I find the more important developer skills are people skills and project management skills. How well do you work with others? How do you resolve conflicts? What's your methodology for grouping work-- Jira tickets, sprints, etc?

But almost none of the interviewers seemed to care. They wanted to know what exotic technology skills I had, not that I could work with project managers and marketers effectively.

Take-home projects are more time-consuming but the least unfair, whereas whiteboard coding is the shortest but most unfair.

I blame Google for this curse. I hope the next time I go looking for a job this process has changed.


Same. Being so far out of school (10 years in the industry) I really struggle a ton with these interviews. It's really only 10% relevant to my day to day work. I think to get through a Google-level onsite I would probably have to practice for a year, couple of hours a day. I just got a new job at a company that doesn't do any algorithm testing and that's how it's always been. I guess I'm maybe in the "false negative" threshold that all the hot companies are fine with.

Asking someone with your amount of experience a coding exercise is silly. You wouldn't have lasted 15+ years if you didn't know how to code. Spend more time evaluating the "softer skills," since more experienced engineers have a bigger impact on culture and process.

Right?

Ask me about past projects. Want GitHub examples? Fine. But whiteboard coding some non-real-world problem?

I get that companies need some sort of filter, but whiteboard coding is not the answer, IMHO.


Length of tenure is definitely not a good enough gauge.

I've worked with folks with 15+ years that could technically code but they took eons to deliver and their solutions were unmaintainable. Some of them with advanced degrees too.

Small sample size, but the few folks I'm thinking of were such bad hires that could have been avoided if we had them write some code or put the proper emphasis on the coding exercise we had them do.


But being a slow worker is going to be revealed during a whiteboard coding test?

All small programs are maintainable, no interview process will tell you if a developer can deliver large, complex programs that are clean, modularized and easy to maintain because there's no time to do something of the requisite size.

It's true there are experienced devs who suck, but that doesn't mean whiteboard coding is the process that filters them out.


To me, it's not about the code on a whiteboard vs a computer and correctness.

It's about the thought process when breaking down a problem and the ability to organize and communicate their thoughts. It's also about exploring a problem space. How carefully does an engineer consider edge cases? What kinds of things are important to them?

A whiteboard to me is a much simpler and accessible medium through which to explore a problem vs setting up an environment and having to type code and dealing with all the minutiae that comes with actual development.

Of course, it isn't the ultimate method of evaluating a candidate but it's certainly valuable.


If the goal is to test the thought process why not give interviee a self-directed project then ask them to present a 10 minute talk about it? You get some code written to verify the engineer can build something, plus you get confirmation that they can organize their thoughts and effectively communicate them to another engineer.

Isn't that a more realistic scenario? How often do you give an (employed) engineer a task then ask them to immediately explain what they'll do to implement it?


Simple, I want them to work on the same topic as other engineers I've interviewed, so I can benchmark them against each other, and ensure the topic is close to what we work on, and not just what the candidate happens to know a lot about.

It is more realistic, but you can't really expect someone to be novel, and if they're not being novel, you should expect someone else to solve the problem. So this method has problems, and it kind of demands payment for results.

I'm confused by what you mean by self-directed. Would you give the person a specific problem to solve? Or would they be coming up with both the problem and the solution?

How many times did you solve a real problem with capturing all the edge cases in less than 45 minutes?

I think it's important to measure what's actually relevant to the job. If the job entails large periods of coding on the whiteboard, then yes, it's a perfect metric.

If, however, the job requires careful consideration of dependencies, time domain, and, yes, edge cases - then you are NOT testing for that.

Lock the candidate in a room and give a few hours to let her to produce the result would be a better measurement.


When I do whiteboard interviews I want a little bit of code because I'm stunned by the number of people who can't write a loop. But mostly I want to see the design process. I ask for a simplified version of a real feature that has an algorithmic core. This lets us code something but lets us discuss all sorts of edge cases and real world complexities that would come up in a true deployment.

Lots of interviewers suck. That isn't a property of whiteboard interviews.


>I'm stunned by the number of people who can't write a loop

I won't say this is you, but it's funny the number of people who will interview and say something like this and then still give a non-trivial problem/question to whiteboard.

Reminds me of a guy who interviewed me several months ago at a place in Mountain View (not Google, but another).

He started by asking me to create an object with a couple attributes. Then he slowly began to add to the problem by asking for X, then Y, then Z.

Little by little, the code became more complex because he wanted iteration, etc.

He would say "I just want to know that you're able to code."

Later on, I found out he didn't like what I wrote, meanwhile all the basic elements of coding he wanted I was able to add without any problems and I met his specs.

If there's a "communication issue" in whiteboarding, perhaps the interviewees shouldn't shoulder all of the blame. Perhaps the interviewers need to temper their expectations and learn to communicate them better, because obviously there is some disconnect in a situation like this, and it's not the first time I've seen this before.


so let's discuss the edge cases. let's operate with abstract concepts rather than actually write code.

I wonder how many of these people are actually active coders which gives them authority on opinionating on how to interview developers. VPs (especially Chief XYZs) are typically good sales and marketing guys with engineering background that often can only be described as hopelessly out of date (or more politely "has-beens"). They need to keep their heads out of real development stuff.

I'm also frustrated with how people have developed disdain for anything whiteboarding. Asking leetcode puzzles in interviews is bad. Asking questions from CTCI is worse and amateurish. But... asking to whiteboard a problem that you had to solve on your own job in limited time is good! Interviewing is hard because crafting such questions in a way that it abstracts away minutia of transient technologies but retains essential problem solving is hard. This is exactly why, a right policy for a company is to establish being an interviewer as a privilege that needs to be earned because not even all brilliant programmers are good at it and interviewers must take time to craft good question and show care. When they don't, they turn to leetcode, pick random question and give whiteboarding a bad name.

And no, whiteboarding is not bad. What is bad is asking to do X using MongoDB and RectJS because technologies like that are transient. Specific technical tasks that employees might perform in a given point in time are transient. Ultimately what matters is ability to learn, process and use that to solve a given problem. Ofcourse, unless you are company who does nothing but data driven web forms. In that case, yes, go ahead and ask candidate to do just that.


I find it weird that the responses seem to draw a distinction between whiteboards and coderpad. The assumption seems to be that the problem making the whole thing stressful and unnatural was the communication medium and not the fact that it's a super time compressed artificial problem with many unstated considerations and a tremendously outsized influence on the rest of your life, no pressure, just talk through everything exactly like you never do.

Most of the problem seems to me fundamentally unaddressable without verifiable portfolios, but those have their own problems. Even in industries where portfolios are standard, plagiarism is a thing - how do you get the verifiable part? I want to hire someone great, not just someone who was on the same team as someone great.


Even just coding on a computer with the screen cast up on a big monitor or projector would be a vast improvement over literally writing on a physical white board.

If you must do whiteboard interviews, here's a technique I've used with great effect:

Have someone else pick a coding problem (that you as the interviewer don't know beforehand), and work on it from scratch together with the candidate.

Being upfront with the candidate that you don't know the answer yourself puts the candidate at ease, and you'll be able to better judge the candidate's soft skills (communication, critical thinking, empathy in case I don't understand the problem).


I like this idea. Personally, I struggle with knowing that the interviewer knows the answer. My wife's in medicine and she and her colleagues call this process "Guess what I'm thinking?" I prefer to have dialog and come to a conclusion together, and I feel it gets what you want out of an interview: how does the candidate think, how deep is their understanding of the technology, how do they communicate, and would you enjoy working with them.

The term "whiteboard interview" seems to mostly refer to "solving algorithmic/coding/puzzle problems on a whiteboard", which I agree is almost always a waste of time for a software engineering position.

As the article mentions though, the term is a bit vague and is overly broad; for example if you're doing a system design question, I'd argue that the whiteboard is the best choice for an interview, since that's how you're most likely to collaboratively sketch the design of a system in the real world.

I think the problem can be restated at a more general level; does the interview test the sort of skills that the job requires? Most people here are correctly pointing out that the skill/knowledge required to write out pseudocode for quicksort is almost entirely uncorrelated to the skills involved in most software jobs.


Whiteboards, in practice, are never used for writing strict code. They're used for high-level diagramming and high-level pseudocode.

The only time I've used whiteboards in my job is either when I need to hash out a solution or approach with my coworkers, because I'm confused or don't understand the problem, or when I need to understand high-level architecture for a system. It's a tool for clearing one's thoughts and for getting a team "on the same page".

If you're hiring someone to code-monkey a bunch of JIRA bugs, then whiteboarding might not be a relevant test for them. If you are hiring someone to build out new features efficiently or redesign architecture, then whiteboarding may be useful for having them describe at a high-level how they would solve problems. In both cases, writing syntactically flawless solutions on a whiteboard is a waste of time for both the interviewer and interviewee.


At a big 4 company recently, they specifically told me "avoid writing pseudocode"

Most selective companies require you to have near correct code in the most efficient algorithm, clean, correct, concise, with all edge cases in about 30-45 minutes depending on the question. They also seem to love dynamic programming algorithms and competitive programming tricks (the less common stuff you glossed over in an advanced algorithms class).

I say this as someone who worked at one and interviewed at others. You really do need to treat it like an exam.


Interviews of the sort you describe are like judging a fish by its ability to climb a tree. Indeed, whiteboards in interviews are used nothing like they are in real work. I'd hope more companies try and make interviewing closer to an actual work environment where the candidate can comfortably use their computer for solving the interview problem, using a whiteboard solely for communicating concepts and other surface level issues.

> "Whiteboarding" has become too large of an umbrella term, one that groups together everything that's wrong with the interview process.

That general premise is right, we've lumped too much into the term "whiteboarding", and it's worth unpacking into the different interviewing practices we may like or dislike. Some things people don't like have nothing to do with an actual whiteboard (e.g. testing esoteric CS knowledge or deliberately creating a stressful environments), and some things that involve a whiteboard IMO are ok (e.g. sketching out a system diagram).


Yes. The whiteboarding that gets hate is effectively the one where you would be asked to write a depth first traversal or similar, in some verbose language, correctly. On a whiteboard.

That is STILL a thing (judging by HN) and it's useless. I don't think anyone would ever think it's a bad idea to have a whiteboard on hand if a candidate is asked to describe how they would design some nontrivial system. Being asked to describe something without a whiteboard in that case, is even harder. The objection you often get for the latter kind is that it tends to benefit the extroverted kind that likes to babble and sketch, whereas a candidate who would prefer ten minutes alone with a pen and paper might not do so well. I think are some merits to that complaint, but I also know from experience that being able to babble and sketch is really important.


Whiteboard is GREAT for communicating design or technical ideas (e.g, what is consistent hashing, can you show how you'd merge N sorted lists schematically?). And these skills are super important in both big companies and startups. And we should definitely test candidates in these areas using whiteboards.

Making engineers write code on whiteboard is just comical. If we weren't so used to it, we'd probably have laughed at the idea. In 2018, any company still using whiteboards to write anything more than pseudocode is just playing it too safe or being really lazy in changing their process. Just give them a laptop and have them use coderpad/skype interviews or any of the plethora of collaborative code editors out there. Or even, dare I say, an IDE. You can still have the whiteboard in the room to discuss the idea. But write the code on a laptop with internet access.


My most recent interview involved a coding assignment, which I topically don't do, but this one was a very interesting challenge that would make a good blog post afterwards so I did it. What was surprising is the interview not only included going over my code from the assignment, but also whiteboard problems about recursion. I've still never used recursion in my day job. Can interviewers really not gauge technical ability from my GitHub as well as chatting about problems and solutions?

Interviewer: I see you have built an app just like ours five years ago. That's great. OK now let's get to the important stuff. How many cakes can you steal from the queen if your duflle bag hold 5 pounds and there are 10 different kinds of cakes?

True story.


You have a software engineering job and you never used recursion of any kind? This strikes me as super odd.

I can only think of a couple occasions in my professional career where recursion made more sense than iteration. Both involved traversing trees with unknown depths (parsing XML and scanning a file system).

That hasn't stopped it from showing up in every programming interview I've ever done.


I haven't really used it for anything other than super simple things with a very tightly bound max input. Stack overflow and honestly many recursive algorithms are quite hard to parse in your head especially once you add some edge cases and some other entropy.

> Stack overflow

Well, yeah, other than tail recursion with tail call optimization, stack consumption, if not stack overflow, is always an issue.

> and honestly many recursive algorithms are quite hard to parse in your head especially once you add some edge cases and some other entropy.

I find lot of things are easier to conceptualize recursively than iteratively, though parsing really depends a lot of the language.


I do embedded work. In this field some compilers don't even allow recursion.

They might generally use a library that handles a lot of common usages for recursion, like traversing a tree for whatever reason.

A question I've had in an interview was what is the difference between recursion and iteration. Fairly easy to explain, including examples of usage.


It's almost always a norm that you never use recursion in production code. Always convert it to iteration. Bounded iteration.

Depends on the language too, I suppose. I'd be more shocked if they said they had never used recursion, but were using haskell at work.

I too never used it. Recursion is usually an inferior solution.

I think most people that are opposed to coding interviews feel that way because they don't feel confident in their ability to do those interviews well, whereas they do feel confident in their ability to "get work done".

Here's the thing though. Let's say you're the one giving the interview to two people who claim to be able to get shit done. One is able to code up a solution quickly and the other struggles, producing less, or producing something that's flawed. Sure, that second person might actually be productive under the right circumstances, but that doesn't matter because the first person already proved they can code.

That's the whole point of interviews, getting high signal in a short period of time. If you think coding interviews don't provide high signal than propose something better that costs the same amount of time.


Your resume, Github account, demonstration of previous projects, ability to discuss problems you've solved, references from previous coworkers & instructors...

The whiteboard is not providing "high signal". Everything else is. The whiteboard is providing low signal, and taking quite a bit longer to do it.


This doesn't take into consideration how much studying and preparation the person who produced a solution quickly did compared to the person who took longer.

If that person studied much more, then they weren't really "quicker", they were just better prepared.

Perhaps that's still a reason to hire them, but not everyone has time to study lots of programming puzzles before an interview, and this is then less a measurement of speed, and more of preparedness.

It also doesn't take into consideration whether the whiteboard problem being presented is at all relevant to the job being offered.

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