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Death to the Technical Interview
- jrjarrett 12y agoOtherwise, in what possible high-pressure situation will you ever be expected to solve an obscure data structures problem on a whiteboard. With no syntax checking or debugger. In front of three scrutinizing neck-beards. Answer: Never. THIS. ALL OF THIS. I recently had a technical interview where I was asked to write some Java code that printed out every 7th number. I could not, for the life of me, figure out how to do it. And I've been a software engineer for 25 years. I realized later that it was because I was nervous about how I could present myself in this once chance, and that made all the rest of it difficult.
- jrjarrett 12y agoOtherwise, in what possible high-pressure situation will you ever be expected to solve an obscure data structures problem on a whiteboard. With no syntax checking or debugger. In front of three scrutinizing neck-beards. Answer: Never. THIS. ALL OF THIS. I recently had a technical interview where I was asked to write some Java code that printed out every 7th number. I could not, for the life of me, figure out how to do it. And I've been a software engineer for 25 years. I realized later that it was because I was nervous about how I could present myself in this once chance, and that made all the rest of it difficult.
- walshemj 12y agoNo coding is not hard! that's the easy bit. The hard part about the job is 1 Getting the actual real requirements nailed down 2 Designing the system to run in the real world accounting for all those edge cases and falilure modes.
- ayuvar 12y agoThat makes me wonder if a business-analyst or product-manager role should involve a technical interview where you spec out a mock product to see how well you gather requirements.
- kasey_junk 12y agoIf by technical interview, you mean the common process of making someone do a simulacrum of the job they will do over the course of days, in a few overly tense hours, then no I can't possibly recommend that. If on the other hand you are saying, "should I be evaluating product specification and requirements gathering when hiring business analysts, or product managers" then I would say of course! What else would be evaluating them on?
- kasey_junk 12y agoI wouldn't say that coding is the easy bit (if it were I wouldn't have seen so many terrible code bases in my life). I'd say that requirements gathering and systems design are also crucial difficult parts of the process of developing software and any developer acquisition methodology should take them into account as well.
- Retric 12y agoBad code bases are rarely bad due to incompetence so much as changing requirements.
- kasey_junk 12y agoIn your experience. Not to be flippant, but if you are developing software in an environment that has lots of changing requirements, there are ways to write that code and developers who are good in those situations. Similarly, there are environments where static requirements are cornerstone for success. Certain methodologies deal with this environment better than others and certain developers will be more successful than others in these environments.
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- troels 12y agoAbove a certain threshold, yes. But I have seen so much utterly crazy hacked-together crap, which was clearly not caused by changing requirements, but rather either incompetence or negligence. I'm guessing that so have you.
- jarrett 12y ago> Getting the actual real requirements nailed down Wherein the programmer plays the role of social worker. Seriously though, the skill sets are very similar. The client is typically the ultimate source of the requirements, but it's never a simple case of asking the client "what should I build? More often than not, the client doesn't know what s/he wants, wants something that will actually hurt him/her, is actually seven different people who want opposite things, wants the roses simultaneously painted white and red, etc. Which is why I find requirements collection the most challenging part of the job.
- lucasnemeth 12y agoNot on every job. Sometimes coding is the hardest part.
- walshemj 12y agoCan you give a real world example here? developing the algorithm to solve the problem is not coding but design.
- dasil003 12y agoCan't very well separate coding from #2 though.
- danielweber 12y agoStop using other people's bad metrics! Use my bad metrics!
- kasey_junk 12y agoIt is the central problem in the software development community right now that we have no good objective way to measure software quality. Without that measure we can't judge software methodologies (thus the TDD flame wars) and we can't judge software developers (thus the interview flame wars). So in each case we come up with proxies for this measure. Having done the interview side of the fence a lot, my strong intuition is that nearly everything people try to measure in developer acquisition strategies either don't correlate or negatively correlate to hiring good developers. At this point, the only advice I give people about this is figure out a repeatable, measurable process for your organization and measure every single filter you use during hiring. Test the measures on just hired applicants, applicants a few months out, and applicants a few years out. It is time consuming and fraught with problems but there is no magic bullet out of this morass.
- PhrosTT 12y agoYeah I'm completely fed up with this whole GitHub or GTFO mindset. Many good programmers: A.) Are great in their dayjobs and don't wish to spend their free time writing Open Source. Maybe they have families. Maybe they have non-coding hobbies. B.) Work on private repos all the time. Whiteboarding lets me prove raw problem solving IQ without being negatively judged for lack of twitter followers or technical blog posts.
- v64 12y ago> Whiteboarding lets me prove raw problem solving IQ without being negatively judged for lack of twitter followers or technical blog posts. Portfolios allow devs to prove raw problem solving IQ without being negatively judged for lack of documentation or a debugger. There are developers who aren't good at whiteboarding interviews because they don't think that way and work better when they're at a laptop and can refer to other source code and documentation and can run their code continuously as they write it. With those devs, they may not look impressive in a whiteboard interview, but you can look at their GitHub portfolio and draw conclusions about their programming ability. An ideal interview should be holistic and include both off-the-cuff code and polished projects.
- iMark 12y agoI have walked out of technical interviews having spent 40 minutes struggling to write code on a whiteboard, sat down in front of a laptop, and coded a working solution in 5 minutes. For my current job I was provided with the specifications for a simple app to display images from a flickr rss feed and asked to code however I felt was appropriate. It was interesting and fun, and vastly less stressful than any whiteboard test. It was also a great indicator of what working at the company was actually going to be like.
- toomuchtodo 12y ago> I have walked out of technical interviews having spent 40 minutes struggling to write code on a whiteboard, sat down in front of a laptop, and coded a working solution in 5 minutes. This is how I bombed a DevOps role interview at Twilio, but was picked up as a VP of Engineering elsewhere. +1.
- fivedogit 12y agomy twilio interview was the worst I've ever had in my life. Flew coast to coast, aced the tech, aced the preso, then was rejected on the basis of a perceived lack of motivation. In other words, the fact that I didn't already use twilio and sing its praises like a good koolaid guzzler was the only reason. Agree with OP. Coding under pressure is a horrible way to measure good coders, because it's an artificial construct.
- toomuchtodo 12y agoOuch. That's terrible to hear. Sorry about that.
- danielweber 12y agoWhoa. "The guy didn't seem motivated" was the standard empty excuse 10 years ago. They are supposed to say "you wouldn't be a good fit as this time" as the standard empty excuse these days. They need to get with the times.
- akanet 12y ago
- mer10z 12y agoIf I ever get to lead a software team I will make part of our product open source and then ask potential new hires to complete a real task on that codebase. I think that would be the most realistic display of their coding ability and quality and at the same time they could get an idea of how the company manages and reviews code.
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- cfarm 12y agothis is true but at the same time i think great programmers are also really resourceful. cutting off those resources in a standup can make it difficult to evaluate a candidate, especially if the programming question is something that only one party knows about. i think being able to figure out how to get the right answers is much more important than having the candidate know an arbitrary one that the interviewer asks.
- chaostheory 12y agoI hear these complaints all the time, yet not many people complaining actually offer viable solutions for vetting a candidate's ability. That said, I would say Github contributions and maybe paired with StackOverflow activity may be a good substitute for a technical interview when available.
- mordocai 12y agoThe author said Github contributions and/or a specific programming project. My development group does a relatively simple tech interview + a programming project.
- chaostheory 12y agoI stand corrected. I skimmed the post a bit too much.
- FLUX-YOU 12y agoI think it's just a symtpom of an evolving industry. Studied solutions are better than viable solutions, and we may just be studying it without acknowledging that fact. Someone should put some actual researchers on this problem though.
- logicallee 12y agoWe've recently given a huge amount of thought to this idea (how to technically assess applicants) and sought input from many sources. This is because we are building a curated online community of technical (job) profiles, and we have a very strong incentive program for people to sign up. (It's being announced any minute.) In fact, you could say our incentive program is too strong, and we are afraid of getting "CTO/senior web applications developer" with "20 years of Linux and AWS experience" who can't actually define what "ls" is or what "for" does (in any language). So, what shall we do? How can we very strongly incentivize every qualified person to upload their profile, in a way that lets us curate people's actual abilities? The suggestions this article makes, to demand githubs or complete projects done for demonstration purposes, have both been rejected. Sure, it may be a good strong signal. But then so is the signal of someone creating a complete application for your company (complete with branding) to actually A/B test on the front page, and then if it does well, for the canddiate to show up for a 3 month unpaid trial during which he or she must contribute as a full member of the team and can be dismissed at any time for no reason. I guarantee, anyone who passes that test would be a great candidate. The issue is that there are perhaps three people on the planet who would even consider applying to a company on those terms - and they're the original founders' siblings. The problem is that it is not a reasonable burden on job applicants, and neither is a complete github profile, and neither is a complete programming project. It's just too much. What is needed is a smaller burden that is a good, strong signal. We think we've found one, but are not sure. (You can see it on our web site as soon as we announce.) In the mean time, if anyone here has any breakthrough ideas in this space, we would be very interested.
- AnimalMuppet 12y ago> What is needed is a smaller burden that is a good, strong signal. We think we've found one, but are not sure. Even if you don't have the right answer, you at least found the right question.
- JPKab 12y agoI recently drove 3 hours to a technical interview. I had done plenty of screening, including screenshare while I wrote code to the guy's delight. He invited me down for the technical interview. I came down a week later. His wife had just delivered a baby, so he was out. The guys in the room were a business level ex-marine who was there for god knows why, and a technical dude who clearly was pissed he had to sink to the level of doing the interview in the first place. For the first 45 minutes, I aced everything he threw at me, and I noticed that he wouldn't drill in on anything that I clearly knew very well. He kept jumping from topic to topic, and eventually asked to do an extremely tricky SQL query, but write the code to do it in awk on the whiteboard. The job posting said nothing about awk, and I told him I didn't know awk that well. He then sensed i wasn't a command line master (the job posting said nothing about needing to be a fucking sysadmin or know advanced CL stuff) and hammered me on things that I had already said I didn't know. 2 things became clear: He wanted to show off to his boss and make himself look like a badass while simultaneously making me look incompetent. There was no fucking way I was going to accept a job working here if it was offered. I didn't so much as get a phone call or an email to thank me for driving 6 hours round trip. Nothing. Which screams out to me that this company sucked.
- pekk 12y agoThe applicant is always wrong.
- aaronem 12y agoPerhaps your comment was intended as a sarcasm, in which role it serves admirably. I'll please myself nonetheless to answer as though it were genuine: If you want to make absolutely certain that you never, ever hire the best candidate you can find for any of your positions, I can't think of a better way of doing so than to bring this sort of attitude to the hiring process.
- qdog 12y agoYeah, that pretty much sucks. I generally try and ask people about what they did and drill into whatever it is they know, but most interviews I've gone on the interviewer wants you to know the stuff the interviewer knows/is good at.
- jowiar 12y agoHere's what I've been doing. I'm running on an egregiously small sample size right now, but so far, so good. My goal is to answer "Are you honest about what you know, excited and curious about what you don't, willing and able to learn, and driven to excel at the role that we're discussing?" Sometimes answering this requires code, but generally not a whole lot, and mostly I just use it to tease out where someone actually is vs. where they say they are. I don't want to hire a candidate who is best suited to make my problems go away tomorrow. I want, a year or three down the line, to say I built the best team possible. Maybe I can say this because I don't think the "technical" part of what we're doing is the major challenge, though I think that most engineering teams are actually in the same boat as us. Google has far different problems than we do, so their hiring process is rightfully different than ours. And maybe I'm just getting it all wrong. We'll see what happens.
- untog 12y agoI would be more specific - Death to Interview By Whiteboard. I haven't had many, but every whiteboard interview I've had has been miserable. At best I've just about managed to convey what I mean, at worst I don't even understand the question. One particularly memorable exercise had the interviewer write out HTML on the board and ask me to write out the CSS to turn it into a dropdown menu. I didn't even know where to start, because I couldn't construct a mental model of what was going on where. Because outside of the white board interview I never have to. A much better technical interview that I do not with death upon is one that put me in front a computer which was rigged up to a projector that the interviewer could see. We talked through my solution to an exercise as I constructed it, and I was free to switch between the browser and editor as I wanted. You know, like I might in a normal, actual working day. An even even better interview was one that left me in a room for 45 minutes with a task. After that time I sat down with the interviewer and talked through what I did.
- kasey_junk 12y agoI'm not saying that your experience is wrong or weird, but I have encountered just as many people that hate the rigged up projector interview. In my experience, being bad in either one of these interview types is not correlative to being bad at being a developer.
- bbarn 12y ago"Look at github contributions and stackoverflow posts" That's fine for startup-ish hires, but in most of those cases, isn't the candidate being sought out/referred/etc? Almost all of my work is on non-public SCM systems, and frankly, my job doesn't leave a ton of time to post to *overflow sites, and when I go home, I'm home, and spend it with my hobbies and family. I also consider myself a really great developer. Especially in the more corporate .net world. When I review candidates, I find that a simple (at a PC, with resharper installed) coding test, with a prebuilt solution, needing only an implementation of a method done, is a great filter for competency. And after all, rough competency is the most I hope to get out of a coding test. The far more important part is always the stuff like how well I think they'll fit in a team, how their approach to solving problems in general is, etc. Syntax memorization is no longer a measure of a good developer. All it shows is basic competence in a language.
- switch007 12y agoI do love the absurdity in the UK where recent employment contracts (last 5 years or so) often state that "all your everything are belong to us" (IP, copyright, creative output, thoughts, ideas etc), yet companies also want applicants who actively contribute to or release open-source software. Having worked under such terms, I've never felt I could participate in open source without jeopardising the project.
- VLM 12y agoIts weasel words for they want a noob, recent grad, or a contractor. They don't want "You were doing exactly the same thing over there, now you'll be doing exactly the same thing over here", because they don't have the money in the budget for a real applicant.
- chadcf 12y agoThis is a big problem in the industry, in order to really be seen as a good candidate you have to make your work a second part time job so you have something to show off publicly. If you work for a private company with private software, you could still be really good but looking at your github profile, many will dismiss you right away. Of course the flip side is, you can probably get by with minimal outside work. Do some code katas, have an up to date best practices simple app in github, etc. I think as long as you have something in github that looks good it will do the job, even if you're not working extra hours daily on open source projects.
- josephschmoe 12y agoIambob doesn't account for the fact that interviewing candidates falls into a Simpson's Paradox for this instance. You have two cohorts which comprise a majority of your applicants: 1. Unemployed, X% qualified. Has time. 2. Employed, 100-X% qualified. Does not have time. X is small. If both candidates are qualified, tests for X also find how qualified they are so they can be compared. His methods are objectively better, provided that both candidates have the same amount of free time. If you compare two unemployed engineers, you'll pick the right one. If you compare two employed engineers, you'll pick the right one. If you compare an unemployed engineer vs an employed one, however, you'll probably pick the unemployed engineer, even if the employed one is better. Because he doesn't have as much time for your homework or to maintain a Github profile. Thus, if you're comparing 30 engineers, half of whom are employed, you'll pick the most qualified unemployed candidate, rather than the objectively most qualified candidate. That's why, even if the test is slightly worse, with an interview room only test you'll consistently pick the better candidate: a large, large segment of talented candidates are employed. I would love a statistical analysis of Simpson's Paradox and technical interview methods if anyone's ever done one.
- GregorStocks 12y agoIf you're employed, it's generally a lot easier to find the time to do a coding problem at home than it is to actually physically come in during a weekday and talk to people.
- loumf 12y agoTake a sick day -- have a "doctor's appt". It's really not that big a deal. "Hey, I have to come right from work, do you mind if I don't wear a suit so I don't have to go home and change" -- it's a well-understood problem.
- nilkn 12y agoSurely, though, it's easier to just do a coding problem in the evening? No worries about coming up with a lie for your employer, no possibility of suspicion, and some people have to take sick days out of their vacation time sadly.
- c0deporn 12y agoToo many times I've been in a technical interview where they asked me to define design patterns, but never ask me when/how to actually use them. I usually decline their offers. When I interview candidates, I look for a good foundation for what they will be working with like do they know the difference between class and struct and the implications of using them (day 1 kind of stuff). Then I ask them about how they would go about solving a problem they were unfamiliar with. Google-foo is a skill that must be learned and honed. I don't care if you can spit off all sorts of acronyms, I want to know if you are capable of using common sense to solve a problem. Last but not least, how do they stay up-to-date and relevant. Not looking for the 8 to 5 developers and not interested in those cutting-edge guys either. Must have good understanding of the basics, principals and skills in problem solving. Telling a block of code that you have a masters in CS will NOT make the bug go away.
- steverb 12y agoSadly, if you know what a design pattern is and can name two then you are head and shoulders above 95% of developers. Source: Been interviewing supposedly senior level candidates for the last three weeks.
- c0deporn 12y agoThe term "senior developer" is an unfortunate one because it can mean a really good, skilled and experienced developer. But it usually means 20 years of experience (1yr exp * 20) or they've just been around so long that the "senior" part refers to age.
- cunac 12y agoand special bonus points if those two are not Factory and Singleton :-)
- neilk 12y agoOP has the wrong assumptions. The live technical interview is already well-known to be flawed, because qualified people often fail. However, only qualified people can pass. However, it's true that coding exercises that can be completed in an interview are arbitrary and abstract (by necessity, since you have no context.) In my opinion one should use live coding exercises to test fluency -- can you code at the level you are claiming? Debugging something might be a better test. Then pair that up with a short (short!) take home exam to test problem-solving. The one thing that really has to go is whiteboard coding. Ask the candidate to bring a laptop or give them a used one. OP also thinks that high-pressure situations don't occur with programming. But if you work on the web, sooner or later you will be debugging a tricky issue that's costing that company $X per hour while your all your managers up to the CEO hover behind your desk. Being able to communicate with non-technical people and inspire their confidence is also very important. Often more important than coding ability.
- kasey_junk 12y ago"However, only qualified people can pass." If only this were true. There is a whole class of people out there who are stellar face to face and not great for your specific technical/business situation.
- neilk 12y agoYeah. To be honest, there are cases where I've been that guy. But past a certain level, it's your job to explain your own weaknesses too. I just had a technical interview the other week and they relied way too much on definitions and whether I'd heard of this and that. I happen to do great at those but I want to be sure I can be productive (the position uses Elixir, which I'm totally unfamiliar with) so I'm suggesting they give me a take-home exam.
- venomsnake 12y agoThe assumption that only qualified people can pass a technical interview is somewhat wrong. I have had my fair share of false positives. And probably I have been one or two times the false positive. And this is something that everyone can relate I suppose. Sometimes you just need luck - like the gotcha question being something you have debugged soon in a language you are not that competent at.
- vezzy-fnord 12y agoGithub profile: How many repo's do they have? How active are they? Do they contribute to open source projects? And then, of course, the obvious code quality questions. I thought most people came to the conclusion that this is a horrible metric by which to gauge competence? Then again... Now us Python developers, Ruby developers, Java developers, PHP developers, and (God help you) Perl developers, let us put aside our meaningless and largely annoying quibbles to unite under a single banner. For once, let's say who cares whether Django or Rails is the superior framework and just join our voices to call for an end to the modern technical interview. The final paragraph shows what demographic the OP belongs to, so it's hardly a surprise they think that way.
- FLUX-YOU 12y agoI've tailored my learning and goals around the fact that projects are one way to get my foot in the door without a degree or experience. Otherwise, they just have to take my good word and burn time interviewing me. I thought this would be true regardless of development sector. Once you're dealing with someone who has verifiable experience, then repo activity should be weighed much less (unless it's something really awesome, then chances are you're dealing with an awesome developer). If you're critical of someone lacking github repos but they have experience, then I think it becomes a symptom of "everyone trying to stand out"-itis. It's probably best to have different solutions for different skill/experience levels.
- dap 12y agoJust because it's hard to do technical interviews well doesn't mean that doing them well isn't worthwhile. In my technical interviews, I look to talk through specific technical problems, and they're usually real-world bugs or design issues I've worked through in my job. There's not usually a lot of code involved, and the code isn't that tricky. It doesn't usually even rely on too much specific domain knowledge. It's about being able to take a broad technical question, formalize it a little into something concrete enough to be discussed, identifying constraints on the solution, working towards a solution, reasoning about performance, and discussing tradeoffs of this approach vs. others. In short, it's about technical reasoning. I don't care if we get to the right answer by the end if we've had a fruitful technical discussion. Code samples are a good idea, but they're as deeply problematic as interviews. Most of the code from most of the best engineers I know is closed-source, not on github. 48-hour programming projects can tell you what someone can cobble together, but they don't say anything about the person's attention to longer-term concerns around design or code quality. Moreover, being able to code up a technical solution to a 48-hour problem is like basic literacy: I expect at least that, but I really want to find people who can make forward progress on the uncertainties associated with a 3-month project, at least.
- samrift 12y agoA technical interview whiteboard code or data structure gotchas or mt. fuji questions is a bad interview. It sucks that most technical interviews are bad, but that means we should fix them not remove them. Our team "technical interviews" by having a technology discussion with the applicant. One of the first lines of question is figuring out what they are most familiar with so we can discuss that particular thing, area, library, or whatever. If a person can't discuss what they are most familiar with in the high-pressure interview, I'm not sure they can discuss something they just learned about in a team design meeting either. It's also a great way for the candidate to figure out if he wants to work with us - something that is just as important as the reverse. Quit making technical interviews a quiz show. Quit checking off boxes on your form. Quit with BAD technical interviews. But don't remove them entirely - that's just as dumb. *ps: github as a metric is also a bad metric.
- manishsharan 12y agoWrong conclusion! It is not the technical interview that is a problem; it is the interviewer. I sit quite often on both sides of the table and I have noticed that some interviewers are eager to show off their skills more than trying to learn about the candidate. Or they are auditioning bros to go clubbing or to invite to barbecues . I have not ever cleared a tech interview when I was interviewed by guys in twenties or early thirties. I have a 100% success rate when I am interviewed by people,all races and gender , over 40. When I am conducting interviews, I place a high degree of importance on the candidates aptitude and approach to problem solving and I usually build up a pretty good team with candidates who the bros wouldn't hire. Some people suggest looking at candidate's github repo; this would not work for enterprise software developers and most large companies have restrictions on what code a developer can claim as his/her own and publish. edit : grammar
- mrfusion 12y agoI've noticed the age thing too! I thought it was just me. Any thoughts on why there's that distinction?
- kasey_junk 12y agoI'd say that contra to what a lot of propaganda will tell you, being experienced matters. In interviewing a diversity of experience is especially crucial. Further, being experienced at interviewing is super important, and that sort of experience is even harder to gain than other software experience.
- manishsharan 12y agoI think older people focus on solving problems ; younger interviewers focus on techniques and APIs.
- DatBear 12y agoDown with the technical interview, up with the Github profile! I guess that's great for people that have a sweet Github profile...
- deleted 12y ago[deleted]
- loumf 12y agoBefore I tech screen anyone, I have a short email or phone chat with them. I ask if they program every day and how much of a typical recent day was spent programming. If it sounds like they are currently not full-time employed as a programmer (and not programming a lot), I explain that they will probably not do well on technical tests (mine or anyone else's) if they don't practice. I recommend they just find some sample questions online and practice them -- let me know when they think they are ready. I explain it's just like playing an instrument -- you wouldn't audition without practicing beforehand, right? I also explain that it's very hard to tell the difference between someone who is rusty and someone who is not skilled -- I want them to be at their best. To everyone, currently programming or not, I explain what the interview will be and everything about it that I can except for the questions. I am hoping they will self-select out if they know they can't program (or talk to me about it). I also explain that I am not looking for people who know all of the answers, but I am trying to calibrate their resume and see what it's like to collaborate. All tech screens are conducted in the language of the applicant's choice. The meta-question I am asking them: If I tell you a bunch of requirements and some guidelines for success, will you do the work necessary to succeed.
- atom-morgan 12y agoIf only everyone who has to conduct an interview thought like this.
- halayli 12y agoTwo techniques worked really well for me when interviewing candidates: Take a problem that I recently solved or trying to solve and turn it into an interview question. Email them a coding problem that's very easy to understand.
- loumf 12y agoThe thing to realize is that the question is as much about collaboration and technical conversation as it is about coding. Or, at least, it is for me.
- cpprototypes 12y agoThe primary issue with the current technical interview style is this: No one likes working on a problem with someone watching them constantly. Most companies are underestimating the power of social presence. Just knowing that someone is watching you makes a huge difference. Imagine there are two people taking a high pressure test like the SAT. In one version, it's the normal setup, a room with a desk and silence. In another, there is someone constantly watching your paper and everything you do. Put yourself in that position and it's obvious that the second situation is much more stressful. The effect is not limited to physical presence, it can also happen over a phone interview with screensharing. Consider all these thoughts that a candidate is probably thinking while trying to solve the problem: What's this person thinking? Am I working too slowly? Should I type code faster? Is this solution what he/she is looking for? Should I talk more? I'm not sure what to say, ok stop panicking, just focus on the problem. Should I say I'm focusing on the problem? The problem is not the whiteboard. The problem is that there is someone constantly looking at the whiteboard. The solution is simple and I'm surprised that I've never seen a company try it. Give the candidate a big whiteboard or a laptop with no network connection. Give a problem and leave the room. Come back later. When depends on the size and scale of the problem. Put the code on a projector and get other engineers in the room. Now discuss the code. Run the code through some sample data. Make some criticisms and see how the candidate defends their decisions. It's like a long code review session. Digressions are ok. Maybe talking some data persistence will lead to a discussion about caching. Maybe asking why the candidate did something will lead to talking about concurrency. A bad candidate can't BS through this. They wrote the code, they have to either explain or defend it. And the way they talk about things also gives a chance to show their level of experience. The way a junior dev talks and a senior dev talks is very different. The key thing is, let the candidate have some time alone to work. Stop pressuring them with having an engineer there constantly. The engineer doesn't like it because they would rather be working on something. The candidate doesn't like it because it's stressful. And there's no benefit to having someone there constantly. You don't need to hear their thought process in real time. You don't need to see the iterations they went through before the final solution. If you really want to know, you can find out all these things in the discussion session afterwards.
- louthy 12y ago
- bokglobule 12y agoActually, asking people to write some code in (or for) an interview is the best way to go with technical interviews. I haven't found any other approach that's better given the time constraints for an interview (and I've been interviewing ppl for 20+ years). The hard part is coming up with what programming problem to ask a candidate that's fair to the candidate yet provides insight into their capability. For us, I created a simple data structure problem that hits a smattering of things that are taught in a typical undergrad CS curriculum (trees, recursion, etc). The candidate has about 30min to write the code for this in their preferred language using a plain text editor. I care less about perfect syntax when working with libraries, etc. and more about whether the candidate can take a problem statement and turn it into working code. For an on-site interview, I send the candidate a description (along with screenshots) of a small web app project that hits some UI, some DB, some business layer. I encourage them to innovate around my description and surprise me. They get a couple of days to implement, then show up with their laptop and demo it. I want to see working software, then a deep dive into their code. Typically by the end of the on-site interview, we have a really good idea whether this person knows their trade or not. It's helped me sniff out the pretenders pretty well over the years. The ones I hire are the ones who obviously take pride in their craft, know why they picked various implementation approaches, and can explain the technology they used.
- JimboOmega 12y agoI personally think the "CS curriculum" style problems are a bit ridiculous. How often have I implemented a tree as a professional? Especially in a sense where I need to think about the difference between the types? (Is it a red-black tree? A binary search tree? A b-tree? Which ones are sub-types of others? etc.) The result being that before the usual technical interview I dust off the old CS textbooks and try to hit all the high points. I like the idea of a small program - especially a business-relevant one like you mention. But if you limit it to 30 minutes, often that 30 minutes could easily be eaten up by setup of environment... which can be a huge timesink.
- bokglobule 12y agoYou're right about making sure the problem is gauged to the time available for the interview. I had my senior and lead developers work through the problem individually to see how long it took them. Typically, 10-15 minutes. And they didn't see the problem ahead of time. Wasn't meant to be tricky, but rather do they understand a basic data structure we use all the time in the context of a simple problem. Personally, I don't buy the complaint that asking a candidate to write some code is unfair although I've had a few tell me so. For onsite interviews, I have them spend a couple of nights ahead of time working on a small web app with a few moving parts (UX, DB, validations) to see how they approach writing larger, more real-world code. They demo the app, then show me the code. Some people take real pains with what they do, fully understand what they used and why, and can talk about how they'd improve it if they had more time. Unfortunately, many don't do that for one reason or another. But this tells me what I/we need to know before thinking about hiring someone as a developer.
- jiggy2011 12y agoWhat's the deal with articles putting an animated GIF after every other paragraph? It makes the article 10x harder to read.
- tragic 12y agoIt seems like people have vastly varying ideas about what constitutes a 'technical interview'. For my money, I'd expect that most interviews in any field are technical to some degree. If you're hiring an HR person at any level of seniority at all, presumably you'll be asking questions that bear on employment/tax law, dispute resolution and so forth - in short, questions that bear on a body of specialised knowledge: technical questions. The problem is execution. Having never been asked to do code on a whiteboard, I can't comment on whether that's any use. (I think I'd be OK provided it was acceptable to drop into pseudocode: surely we're not testing for encyclopaedic knowledge of every method in X language's standard library.) 'Homework' challenges have the advantage, if they're executed right, that whoever you're hiring won't be going in completely cold to whatever tech you're using - may as well get some of that newbie-googling done in advance. (Just did one for a job using Mongo/Mongoid - what I knew about that beforehand would have fit on the back of a cigarette packet.)
- VLM 12y ago"I think I'd be OK provided it was acceptable to drop into pseudocode" My experience and impression is its generally the opposite. Whiteboard is a good place for psuedocode, data flow diagrams, schemas, flowcharts, block diagrams, data structures, and bug related examples. Its a pretty bad spot for source code other than one line notes. I usually have scratch paper with scribbles all over it when I'm coding, so that seems fair. I don't think I've ever written anything in Clojure without a REPL open, it would be a weird experience to write something out entirely on a whiteboard without running all the little parts first. Also the test-driven experience is very weird if you can't actually run tests. Its like testing someones teamwork skills by having them work alone, very strange. I feel a professional obligation to begin all projects with a bit of google to at least prove I'm not wasting effort on NIH and find some pitfalls, so the suggestions to test a dev without any net access also feels extremely weird to me. I think the primary fail of tech interviews is its nothing more than a stress test, selecting for candidates who don't really care, or at least are unnaturally calm, and that doesn't seem to correlate very well with ability.
- wldlyinaccurate 12y agoWhat would replace the technical interview if we killed it? When I'm hiring a contractor, I need to know that they really know their stuff and that they can hit the ground running if they join my team. So far, I have found a quick technical interview to be the best "bang for buck" way of doing this. People can have great CVs, active GitHub profiles, etc, but it's only when you speak to them that you realise they aren't what you need. Phone and Skype interviews can be good, but more often than not I'd like a candidate to write up some code for me. Maybe there are some good remote pairing tools that I'm missing out on?
- mbell 12y agoThe biggest problems I've found in tech interviews are: 1) Bad problems - implementing string reverse is a silly question. It has little to do with 'real world' optimization, which is often more about architectural issues: caching, etc. 2) Markerboards - I never, ever write code on a markerboard. Why ask me to write code on a marketboard in an interview? Markerboards are great for high level concept organization, they are terrible for writing code. In the real world I often write a crap implementation of something and make it work, add tests for it, then refactor till it's not crap. Demonstrating that workflow on a markerboard is nearly impossible.
- eranki 12y agoInterviews are hard because programming is an incredibly complex task with few qualified candidates. Any programming challenge other than the most basic questions is going to have a long-tail distribution in the time it takes a person to answer them. It's easy to get hung up on something stupid, especially in a high-pressure situation like an interview. We've all had moments where we missed something "obvious" for weeks on the job. In college they solved the time-pressure problem in tough classes by making the homework really hard and the tests really easy (like the take-home project OP suggested), but that relies on an honor code and the fact that getting a good grade on your homework is not nearly as important as landing a job. Also a lot of great programmers don't want to deal with your bullshit project because they're getting recruited by a million other companies. If some new metrics end up in widespread use, most of the people that pass the test are going to be ones that gamed the system (e.g., added a bunch of GitHub projects), just like the majority of people that get really hard coding puzzles have seen the trick to solving them before. No matter what you'll end up with low true positive/negative rates for any test you do. I think the right way to deal with this is to come up with a bunch of orthogonal tests and then choose candidates that pass a bunch of them. Have them debug a program, have them do web programming, have them talk about a project they did, give them a project to do if you can, etc. The main thing I learned after doing hundreds of interviews is that I have a limited view on how to judge a programmer, and that view translates only so well to the question of "how much value will this person add to our company right now." So yeah, TLDR, I don't think the status quo is great but I don't think any of the solutions proposed over the years are better.
- kator 12y agoI’m torn on this topic, I always tell my teams I hire for Attitude and Aptitude. If you have a good attitude and can learn we can teach you everything you need to learn. If you have a crappy attitude about life we can’t help you. I have been in tech for 30 years and have had to learn so many things that I find it a bit insulting to have a technical interview when clearly we’re all learning every day. If you’re not learning you’re dying. If you get into one of these types of interviews you might want to think twice about the employer. It’s important to remember that interviews go both ways, I’m interviewing you as much as you are interviewing me. To be clear when I’m an employer I’m worried if the candidate isn’t interviewing me. I worry they’re sold on the coolaide and not looking for a good fit that will reward them. People like this never make it in my teams because we can’t have someone who shows up for the wrong reasons. They will just fail and if we hire them it’s not fair to them or our team. That said I interviewed at Valve and they had teams of two go after me and ask me to code on a whiteboard and at one point the team interviewed me on Perl. I’ve been coding in Perl since it was released on UUNET in 1987. The people interviewing me gave me a problem and asked me to code it on a whiteboard. I did and then they kept saying “You have a syntax error” and I kept saying “No I don’t” after a couple minutes of this banter one of them got upset and typed it into his laptop to prove to me I was wrong. Boy was he embarrassed, I’ve been writing in Perl for so long I was certain I was right and this gentleman was certain he knew Perl until he met me. To me this event is proof that the “technical interview” is bogus. It’s a nice to have and certainly will help weed out some people who won’t make it but it also can cause this strange disconnect between skills and raw coding styles and/or understanding of the underlying tech. To me the “technical” interview needs to be real life problems, potentially something your team is struggling with or perhaps has solved recently. You provide the details and see how the person approaches the problem. Do they ask smart questions, are they thinking about how they’d collaborate, how they’ll look at what others have done to approach similar problems in the past. Again, this is about Attitude and Aptitude not about syntax errors and semicolon style. One of the best systems guys I ever hired was a pool man, literally cleaning pools when I met him. And one of the best sales people I’ve ever hired was an English teacher. I don’t care about your background, I’m not hiring you for that, I’m hiring you for your future on my team and how you’ll grow to be a major contributor as we solve crazy hard problems. Past performance does not guarantee future results… To me the only things that make a different are Attitude and Aptitude, the rest we learn together…
- fivedogit 12y agoWord of advice: When they give you the option to use an IDE instead of a whiteboard or screenshare, do it. When they say, oh you can write in psuedocode or you don't have to "really" create the hashmap or array, don't fall for it. ALWAYS WRITE THE CODE FOR REAL. That way, when you hit a roadblock, you can run the program and usually figure out exactly what is wrong very quickly.
- FatalError 12y agoIn my company, I've been told to avoid taking the interview training for as long as possible. That is, don't do the training, because once you do, they will start assigning you interviews. This shows how much of a load on the existing workforce doing technical interviews already is. And the methods that the author is proposing would take even more time. Given the fact that technical interviews have to be done by engineers, there is a tradeoff between the quality of the signal, and the time spent. In my opinion, the biggest problem with technical interviews is that they are an art in themselves, and you can get better at the simply by solving more questions (they can be found easily online). The solution, I think, is to level the playing field by pointing interview candidates to the websites the archive interview questions.