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I interviewed at six top companies in Silicon Valley in six days (usejournal.com)
1012 points by voroninman 30 days ago | hide | past | web | favorite | 692 comments



When I was a new college grad, I felt trapped by the fact that everywhere I looked they wanted several years of experience, and I had none yet. How can I get experience if it's required to get the job?

Now that I am 51, I feel annoyed that all of these stories of interviews involve asking questions about algorithms that rarely come up in real coding, and if they do you should NOT be rolling your own code, you should use the established, battle-tested solution that is out there on the internet if you spend 60 seconds looking for it. Much more important is to have the experience of how code complexity accumulates, and how to mitigate that. I cannot spend hours and hours studying up on these algorithms, there are much more important things (real coding-related things) which I need to learn about, to the extent I have time to do that. What should I choose, pytorch or keras? React or Vue? Go? Kubernetes? Spark? All much more important questions than how to do a breadth-first search.

So, was I wrong then? Or am I wrong now? Perhaps both.


I just graduated, so I'm not dealing with constant internship interviews anymore, but at the time I absolutely hated it.

My frustration isn't exactly like yours (my time is probably a lot less valuable). I feel that the questions are all geared at puzzle solvers.

If you're a puzzle solver, you love answers. You love digging into the details. You love finding out the basic components of a system. I think these are the people who excel in academics.

Almost every other intern I met once I got to the bay area was a puzzle solver. They were also competitive and had amazing grades. And these people LOVED algo questions. Over lunch, they could go through half a dozen questions.

I slipped through the cracks I guess. I'm bored by puzzles, have awful grades (and in a worse program), and not so competitive. What I do enjoy, however, is building up. I like modeling and being about to think at greater and greater levels of abstraction to solve problems that aren't puzzles, but instead open ended questions.

Anyway, I think both of these types of people have a place is software, and only one is given attention


I agree with you. The puzzle solver ABSOLUTELY hate it if you somehow say that the question is flawed. Ie if you think outside the box and render their hypothetical situation flawed. It’s as if they didn’t spend enough time to realize that they are missing the forest for the trees.


"It’s as if they didn’t spend enough time to realize that they are missing the forest for the trees."

In their eyes, they have given you a problem involving a tree from the graph theory and you are insisting on an "out of the box" solution involving woodpeckers.

Let me elaborate.

Usually hypothetical situation is just a way to talk about an abstract problem.

It's easier to visualize and to talk about an egg falling and breaking (or not) than abstract measurements.

Now what you call 'thinking outside the box' is just attacking the irrelevant details of an imaginary situation which is there purely for convinience and can be replaced with another hypothetical situation corresponding to the same abstract problem.


To be fair, almost everyone hates it when you show them they are wrong. Especially in the setting where they are supposed to be judging you, remember? And even in normal settings it pays to think about how some critique will be received by the other side. It's a slippery slope in the interview... For me it would raise red flags if the flaw was pointed out in an inappropriate manner. After all, this is the person who would be involved in code reviews where sensitivity to other people's feelings (and egos) is very important.


> they are supposed to be judging you, remember?

It's actually supposed to be mutual judgement. But I agree: be respectful if you decide to drop a remark about the relevance of the question. There are enough reasons to treat people with respect even if you can afford to turn them down.


> It's actually supposed to be mutual judgement.

Agreed, I was being sarcastic.


It didn't come across as sarcastic to me, btw


I like solving puzzles. I like algorithms. Every once in a while I even get to use them at my job! Solving these kinds of things is at most 5-10% of a developer’s job, and that’s probably a stretch in reality. The number of times I’ve seen things like dynamic programming come up in a real world application are vanishingly small, and rarely will you need to roll your own implementation rather than using a third party library. Even if you’re working on a library like that, considerations of good software design principles, infrastructure and the like will consume a large portion of your time.


I am like you. For me, the solution has been build something and show it off. Building a great and useful app rarely requires Herculean feats of logic and puzzle solving.


Years ago I was rejected by Google for a permanent position, then a year later employed at a much better rate as a contractor in the same building I'd interviewed in. I'd built a relatively cool app (full stack, from Linux to Tornado to JavaScript to UX), like Secret or YikYak (but a few years before either).

The people in Creative Lab were impressed with the ride range of knowledge I had, the SRE guys who rejected me got stuck into me for mixing up some VMware terminology.


My current problem is that I built an app and showed of to some gov agencies, and now that demo app is solving their business problems.


>> "What I do enjoy, however, is building up. I like modeling and being about to think at greater and greater levels of abstraction to solve problems that aren't puzzles, but instead open ended questions."

In my opinion, you will do well if you focus on building your own business sooner or later.


What an odd thing to suggest. Owning a business isn't for everyone. Not by a long shot.


No, it is not. But grand parent comment was giving this advice based on the quoted specifics and not for everyone.


And most importantly, the commenter gave one's suggestion based on representiveness, which are not facts. The rest follows from here.


But building something from scratch, even if non-profit, is the easiest way to get a job you really want. And at the same time you can find out that you like doing actual business and smoothly transition. It's a win-win IMO.


Honestly, it sounds like you may be geared more towards software architecture rather than software development. If you like the sound of the bigger picture more than the details, it might be something you could look into.


Is it possible to even get into software architecture without pretty significant experience? From my experience in the workplace anybody making purely architectural decisions without having to implement them is a team lead or higher in the organizational architecture.


Not sure it would happen that way out of choice, but the role can get unexpectedly thrust upon someone, experienced or not (Think startups, desperate to make ends meet with a handful of inexperienced engineers...or even at medium sized companies, remember back when Google had "20% projects"?). At startups especially though: they don't have money to go out of their way to hire an overpriced "experienced software architect"...

It goes something like: "Hey, new Engineer, I need you to work on experimental feature X". - Then the engineer builds system Y to provide feature X, probably poorly architected and not scalable, not expecting it to go anywhere. Some months later, app containing feature X gets distributed to thousands of users, or goes viral and hits millions of users.

Congratulations, like it or not, you have now become the lead architect of the now-widely-deployed "experimental" system Y, and you are going to either crash and burn or become a damn good software architect by maintaining it out of sheer necessity. Later, you find yourself putting "Lead Software Designer" on your resume, having earned that role and title.

A lot of successful software was originally designed "by mistake" and grows far, far greater than its original purpose. And in contrast, you get the well-designed software that was properly architected, but never goes anywhere because it never saw the light of a successful deployment at scale.


I think you’ve accurately described the vast, vast majority of production code that’s hasn’t been through a second wave of engineers/management and rewritten. If it works, and requirements aren’t changing, then your MVP has become the gold standard


It’s the best way to get into it anyway. Making architectural decisions without experience implementing them sounds like a recipe for disaster to me.


Which makes sense right? Same reason a military general doesn’t start as a general. Architecture takes experience in the weeds to give a breadth you can leverage as you reason through architecture. Architecture isn’t aslways black and white decision making based on some specs which is where experience can help a ton.


Generals often start out as lieutenants though (e.g. officer academy drops you in on a higher rank).


In the U.S. military this is not true. People graduating from OCS, ROTC, or one of the academies start off at O-1 (2nd Lieutenant).


What's your disagreement? 1st Lieutenant vs 2nd Lieutenant? Lieutenant is commonly used to refer to both.

Or are you saying that you start of at O-1 and not a higher paygrade? If that's the case, the OP was pointing out that you start off outranking enlisted service members, not that you start out above O-1.


Well, I misread the comment I responded to. I thought they said that academy graduates don’t start off at lieutenant and start off at a higher rate.


No I wouldn’t think so. But knowing about a role and angling towards it early if that sounds more interesting is hopefully helpful information.


Yes it is possible.


I like roles where I get to do both! I've found that a lot of problems come from these being different roles, and the developers not really understanding or buying into the vision of the architects (who might be able to see the big picture, but can often make decisions that make no sense due to being removed from the details of the existing implementation).

Of course in really large companies I suppose having these as a seperate role is a necessary evil. But I still think there should be much more collaboration and interaction between people in these different roles than I generally see.


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Not really, not at all. Software architecture is a lot about wisdom - how to anticipate future changes. Often user interfaces need to be carefully and gently designed so that the user has no surprises. Diligence from the user should not be assumed, the user interface must emphasize tricky parts and make choices less onerous, etc. Scalability is preferrably achieved by simple code + hardware/vms rather than overoptimized code which depends on "irreplaceable" programmers - what if they fall sick, or leave the company? etc. I think all of this is experience accrued over many years, and with facing many failures.

I have found that the data structures that you need are often simple trees and hashes. Database design is probably more important. I often shake my head at students doing hours of dynamic programming to crack interviews. In the past year, how many problems in your company have you solved through dynamic programming? I suspect, not many.


In the real world software architecture is rarely about “data structures”. Software architecture is about teasing out the needs of the customer - whether that be internal or external - and knowing how to design systems that are maintainable, scalable, fault tolerant, etc.


Scalable, fault tolerant systems is a distributed systems problem, which is a harder form of data structures problem.


Yes but unless you are actually working on creating the system that other people implement, you are just using work made by others. You don’t need to know the ins and outs of various gossip protocols.


Potentially two things here:

1) Gathering requirements.

2) Turning those requirements into data structures.

I think a lot of companies will separate those into different roles, but I strongly believe that's a costly mistake in most situations. There's a feedback loop. Requirements inform your data structures, but your data structures help you contextualize (not pollute) your requirements. If you're working with an existing system, you also want to understand current structures in order to guide requirements. By guide, I don't mean to ignore pain, but if you're building a system to support multiple clients / users, then the real trick is to figure out how to do that in a cost-effective and elegant way.

When these roles are separated, and the requirements are gathered without knowledge of the structures, I believe you're setting yourself for failure in the long term (spaghetti code / everyone gets something different).

Getting these to gel is the puzzle I'm personally passionate about. I don't mind what I would call the math side of programming / code puzzles, but it simply doesn't give me the endorphin rush that building a system that elegantly ties things together does. The best is when you're working towards that or have achieved that and inspiration for further possibilities, improvements, efficiencies start popping up.

I'm not sure how you test for this as part of the hiring process, at least not efficiently. I do think we get better at this with experience, but I doubt it's exclusive to seasoned developers.


But still “data structures” in the context of most businesses are more Domain Driven Design “Domain Contexts”, “Aggregate Roots”, type structures than any type of complicated CS type data structures.


Parent was discussing not being interested in algo design, rather than not knowing data structures.


That depends on what is meant by software architecture. If you mean the structuring of a system to achieve good or (particularly) consistent worst-case performance, maybe you are right. But if architecture is used to mean the design of a system to satisfy users (and present a clean, extensible, meaningful interface) then it's really a conceptual job that has more to do with design skills than optimized algorithms.


Being able to make a clean interface, as in a clean API, or useful one, is a data structures/algorithms problem and often a distributed systems problem. Many API's are technically impossible to use correctly. For example they might not let you do two things atomically that need to be. Or they might suffer enormously because they don't version their information properly, resulting in client/server disagreements over the nature of reality that are impossible to avoid. Or you get components that are impossible to interrupt cleanly or shut down safely.

It's not the same thing as some piddly twenty minute problem -- it's harder, requires some experience, and it has the same kind of aptitude. Consider it a rule that people that can't handle data structures problems are going to create systems architecture problems.


In my experience, architecture requires broad but not deep knowledge of data structures and algorithms. The best architects have both, but even very good architects struggle to remember algorithmic tricks on the spot and write detailed code without tools or references. People who can do that easily are often the last to think of things like fault tolerance.


You don't have to be some string algorithms weenie, but the kind of people who "absolutely hated" algorithms problems in my experience, some of it personal and some of it vicarious, are bad at making architectural decisions with far-reaching consequences. It's overlapping subject matter which uses the same kind of aptitude. It's not that to be good at architectural decision-making you need to be prepped for an emergency Google Code Jam.


A more charitable interpretation is that they absolutely hated "constant internship interviews".

In my experience, algorithm interviews aren't even very good at measuring aptitude for algorithms. Recent study and aptitude for the format have too much influence. Asking candidates about architecture has been much better at predicting their aptitude for architecture.


I don't necessarily disagree with that -- what kicked off my reply was the statement, "Honestly, it sounds like you may be geared more towards software architecture rather than software development." (And, you know, rereading that sentence removes any doubt I had about the correctness of my initial response.)

If you can rigorously ask architecture questions, and don't let people get away with hand-waving, that sounds fine. I've been asked good architecture questions and I've been badly asked bad architecture questions too, so... it depends on the question, and how you ask.


Designing something on an architectural level really isn't always a data structures and algorithms problem. Take the web, for example. REST isn't complicated, but it does the job and it opened up more possibilities than any other invention since timesharing.

As other commenters have noted, choosing an architecture for a system may have more to do with vision, common sense, and even imagination. And the web is such a great example of this, maybe the classic example. As you probably know, it's possible to write a webserver without having a clue about fancy data structures or algorithms. It's the imaginative composition of pre-existing features that creates the architecture.

Another example would be the extensibility of Emacs through elisp. Consider the notion of hooks which essentially allow utility functions to be customized by the user. It's a purely architectural concept.

Or the Unix philosophy: small utilities that read and write text, linked by pipes. Really no algorithmic complexity to it at all.

It feels problematic to me that you are saying to someone that they "need to stay far, far away" from some aspect of computing. It's a kind of gatekeeping. Sure, an outfit like NASA needs to make sure that they don't have amateurs writing their systems software. But in the industry more broadly, people have to be given permission to pursue whatever interests them. It's important, for diversity and the invention of new applications, that "differently able" coders aren't told, by intimidating stereotypical computer science types, that they don't have the aptitude to architect a useful system, or that it's "a rule" that people with their skills will just create problems.

Vision and a perspective that differs from the norm are a lot rarer and potentially more valuable than the ability to apply software engineering principles. Architecture, in the broadest sense, is precisely the area where these "outside the box" contributions are likely to be valuable. Consider the invention of the Wiki. It came out of the pattern language world, it was a hugely beneficial innovation, and it has almost zero data structures/algorithms complexity behind it.

I'd even argue that the examples of pitfalls that you list are more clerical matters of systems programming than cases where architectural design principles are lacking.

(And even the professionals who can reliably grind out working code for large systems can get the architecture spectacularly wrong, as the case of the X window system: http://web.archive.org/web/20170920104011/https://minnie.tuh... )


>t feels problematic to me that you are saying to someone that they "need to stay far, far away" from some aspect of computing. It's a kind of gatekeeping. Sure, an outfit like NASA needs to make sure that they don't have amateurs writing their systems software. But in the industry more broadly, people have to be given permission to pursue whatever interests them. It's important, for diversity and the invention of new applications, that "differently able" coders aren't told, by intimidating stereotypical computer science types, that they don't have the aptitude to architect a useful system, or that it's "a rule" that people with their skills will just create problems.

I really needed to hear this thanks.


Calling an idea problematic is a tell that he's not really concerned by matters like whether it's correct or not.

Web servers and clients, for example, are a case where I've seen bad architecting cause months of damage. An Emacs function hook or advice system, likewise, requires care in terms of when the hook is called, and what the rules for their scoping are. It's a bad software architect that thinks they can just slap callbacks on something.


The puzzle solver obsession in SV has always confused me. Seems to me that you would only need a handful of those type of personalities at any software company. The majority of the work is just shoveling so to speak.

I'm no expert but I know a logistics company that has the 30 workers 1 puzzle guy setup. He maybe writes 20 lines of code a week but its on stuff other people cant figure out. However if he was the only type there literally nothing would ever get done.


You're better suited for research which is about working long term on open problems.


I think the opposite would be true; research might benefit from puzzle solving, and software engineering is precisely the discipline of building up and reasoning about layers of abstraction and components of a system.


Research is a grind when it's not about writing grant proposals and then it's a different grind.


Is BFS really that hard, especially if the interviewer is willing to talk it out with you and doesn't care a lot about finding the most efficient solution possible?

I've been out of college more than 10 years now, do a mix of hardware and software (so am not coding all day everyday) and I can hack together algorithms like BFS if I spend a couple of minutes thinking about it.

I get that there are many awful interviewers out there and that hiring is pretty broken, but BFS seems like a pretty reasonable interview question, so long as the interviewer talks through what it actually needs to do and isn't only looking for a memorized answer. The question is well contained, doesn't require the candidate to know any specific API or framework, and can be implemented in pretty much any language. Probably the biggest downside to it is it's such a common question that many candidates study it ahead of time which makes it a worse filter.


You and a lot of other commenters are getting hung up on the BFS example. It's just that - an example. There are dozens of algorithms that are "common" enough to be asked about and diminishing returns to having them all memorized.


Except you don't need to have them _memorized_. You shouldn't. That's not the point.


But given it is straightforward to memorize, it isn’t a good test.


Except all of these questions can be grouped into a category of the same kinds of problem and it is in fact spending time to find out that pattern and which category from sliding window, nested intervals, recursion and dynamic programming it belongs to


If you memorize them you appear more competent


Sure, but that's my point. So long as the interviewer is telling you what they'd actually like you to do, you should be able to just derive the algorithm you need to do it. At some point the algorithms become difficult enough (particularly if you add lots of constraints like efficiency) that it's pretty unreasonable to expect that in an interview though, and at that point it's a bad question.

Rather than memorizing a thousand algorithms, I generally focus on being able to solve problems simply, quickly, and elegantly, which will help in actually doing most jobs.


You're still not getting it. Even for BFS, which is not a hard problem, the current state of the market is that enough people have memorized the BFS recipe so that the interview doesn't allocate much of any time to it. You're not going to have/be given time to "just derive the algorithm" or "solve problems simply, quickly, and elegantly." You're competing against rote speed, which, if you don't implement BFS all day or haven't recently done interview prep, you don't have and you're definitely going to fail.

I've heard people actually defend these useless interviews on correlation grounds, like people who are docile, follow the herd, and "prepare" are good hard-working workers who also tend to have done well in school or look polished in other aspects of life. That's what these interviews are really looking for. So, if you're not a well known expert, suck it up, be a servile cog and follow the script.


It seems like there might be a middle ground, like being willing to play the game, that doesn't imply being "a servile cog?"

The trick seems to be knowing when the game is worth playing. There are certainly situations where competition is too fierce and requires too much preparation, so it's not worth doing if you don't really enjoy the game.

I'm not sure getting hired at a large tech firm is quite that competitive, though? They do hire lots of people all the time.


My first reaction when inplementing anything more than a very simple algorithm is to google the best way to do it.

Of course, I could probably come up with a way to do it by myself. I could probably even come up with an efficient way if I spent an afternoon/day on it.

But why do that when I can google it, and get 3 blog posts and 2 stack overflow answers detailing the different options and the trade offs between them, most likely even with an implementation I can base mine off of?

That's why these interview situations are stupid. They're like school where copying is cheating, whereas in real-world situations copying is a great way of doing something.


> But why do that when I can google it, and get 3 blog posts and 2 stack overflow answers detailing the different options and the trade offs between them, most likely even with an implementation I can base mine off of?

A lot of resources out there are wrong, inaccurate, or not reasonable for your particular context, and it requires a reasonable amount of algorithmic intelligence to be able to sniff out what's appropriate.

If I had a dollar for every high-upvoted SO post that misstates a problem or doesn't offer proper caveats... but I can make that judgment because I've already thought about a related problem in the past.

It's like asking why one should learn how to write properly when Grammarly and spell checkers exist, or why mental arithmetic is useful when we have calculators—at some point those your tools will be inappropriate or unavailable. Search tools are force multipliers, not replacements for personal knowledge and intuition.


> A lot of resources out there are wrong, inaccurate, or not reasonable for your particular context, and it requires a reasonable amount of algorithmic intelligence to be able to sniff out what's appropriate.

Right, and having that algorithmic intelligence is key part of me being a good developer. But testing how someone implements an algorithm in time-scarce circumstances is not a good test of that kind of intelligence because it is likely to favour people who have been exposed to that particular algorithm before (even if they only rote-learnt information about it - as many interviewees seem to do in practice) over people who have the capability to think deeply and reason correctly about it, but have not previously been exposed to that problem.


I'm a data scientist, and google asked me to sum all values of nodes at each height of a tree. I had to implement the tree, bfs, and the algo (which was easy once you have bfs) in a 25 minutes, minus any talky time.

BFS is not something I thought about much in the last 5 years, and quite frankly could care less about. I got stuck when I knew I needed 'something' to finish implementing BFS, but couldn't remember and the google interviewer offered no help. What I couldn't remember was the queue.


>I'm a data scientist, and google asked me to sum all values of nodes at each height of a tree. I had to implement the tree, bfs, and the algo (which was easy once you have bfs) in a 25 minutes, minus any talky time.

THIS is the problem. The (unreasonably) timed nature of the exercise means that the only people that will do well are the people that prep heavily for this specific skill, in much the same way that people about to take the LSAT are likely to do better than it than actual fucking lawyers with proven experience.


Now take this analogy one step further: why aren't lawyers asked stupid timed LSAT questions at every job interview? Because they take a really challenging professional exam called the bar, which is a strong base level guarantee of actual knowledge and competence. Software Eng. have been fighting this kind of credentialing because somehow tech is "top innovative" for such standards. Hence the status quo, and why companies like TripleByte see opprtunity.


> Now take this analogy one step further: why aren't lawyers asked stupid timed LSAT questions at every job interview?

Because which law school they went to is on their resumé and the average LSAT scores for each school are trivially available, tracking very, very closely with school prestige.


Time (and being watched) do make it very unrealistic, but the other thing missing is that programming now is not like in the 1970's, you don't need to memorize much of anything. If you forget something, you look it up, it takes 30 seconds to remind yourself, "oh, yeah, the queue", and then you go. Testing if you can do it without looking it up is not testing the skills you actually need in order to code well.


They didn't let you "Google" it at Google? Something wrong there.


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you are right about any tree traversal would have done, but its not a lot of time and if you end up stuck you dont have a lot of time to backtrack.

a lot of great data scientists dont even know how to use python, let alone implement a tree and tree traversal. there is so much more interesting and pertinent stuff I spend my cycles on learning / keeping in my head than undergrad cs bs.


If the interviewer is willing to talk it out with you, then it is totally a different situation. But, it came up in a recent other HN discussion on tech interviews, and it is an example of something that, if you memorized it, would have a vanishingly small improvement in your ability to get the job done.

But, if you explain what it is in words, and have them whiteboard how to turn those words into pseudocode or somesuch, then it could be a appropriate, sure.


Bfs is just one of examples. I can ask you a question you will not be able to answer without knowing the answer. There is a reason it took researchers years to find those optimal solutions


That always struck me as odd, testing aptitude by memorizing others hard won knowledge.

Who could really solve these problems, error free, on the spot with no prior exposure to underlying concepts?!?


Sure, you can come up with an algorithm question hard and obscure enough that no one will be able to answer it in the time given and no one will have bothered to memorize it because it's so obscure.

That doesn't mean all "implement X algorithm questions" are categorically bad.


This is such a cop out. It took millennia to invent 0. That doesn't mean that 0 is an exceedingly difficult concept to grasp.


Cakes have existed for centuries and I'm sure most people on HN have made cakes at least once in their life.

But put them in a room and say "Make us a 2 layer red velvet cake" with no access to a recipe, and you're not going to get a red velvet cake. It's an easy recipe that most people easily recognize with just a glance, and anyone could make it if they have a recipe on-hand or make red velvet cakes with abnormally high regularity. But most people, even if they're great chefs otherwise, will fail.

Recognizing that a concept exists and implementing a relatively complex concept are different things.


That's absolutely not the case. Many working pastry chefs (I just asked the two that I know) can do exactly what you're asking.


This strikes me as an analogy that does not work in your favor.

To know how to make a novel cake (not a recipe you've memorized), you need to have a good understanding of how the different ingredients interact. You probably even have a good sense of why they're there.

Those seem like exactly the qualities you'd want to look for in a cake maker. Sure, they'll probably be going from recipes in their day to day job. But they'll be able to tweak them intelligently too.


Most tech companies aren't looking for people to reimplement a dozen new variations of quicksort everyday. I mean, some companies really do need people who have countless algorithms ready to go in the back of their mind and the ability to apply them to new and interesting situations all the time, just like some people do need bakers who never need to consult a recipe and can devise new cakes for important events on a whim.

But most restaurants are looking for someone who knows how to cook and use the tools in the kitchen. A chef who doesn't specialize in cakes will still probably be fine if you give them 5 minutes to look up a recipe and make one. In the same way, the overwhelming majority of tech job openings are in need of programmers with some degree of specialization and the ability to know how to look up what they don't know and the experience/knowledge to know how to put that info to use.

The state of programming interviews for the past few decades has been to find people who've memorized all the "recipes" of CS. Most of the jobs, though, are about using some Javascript flavor of the month library and making it work with some other popular library and writing a bunch of interface code. Someone on the team might have to write an implementation of breadth-first search in their toy language, in which case they look up "bfs" on wikipedia and just rewrite the algo given.

Companies are testing employees on how to make cakes when their job will be all about making burgers to order.


But an algorithm or more generally algorithmic thinking is not a collection of rote memories. It's concepts that can be applied broadly. Much in the same way that I'd expect a pastry chef to be able to cook a 2 layer red velvet cake because they know that a red velvet cake is just chocolate, and a 2 later cake is just 2 one layer sheets with icing between. Someone who understands a relatively small set of fundamentals well will be able to perform as well or better than someone who spends weeks memorizing every cake in the dictionary.


I disagree. I don’t know based on what you are making claims, but based on my anecdotical experience knowing fundamentals help low level coders to pass interview but has little to do with performing well. Based on my experience (currently responsible for a huge chunk of a major gaming platform, with hundreds millions users), inflexibility, emotional immaturity, inability to think outside of the box, inability to listen and admit failures, lack of emphaty, not understanding basics of sales(to sell own ideas) are major things that contribute to a bad performance reviews. Our strongest engineers will not pass google interview without preparation (me included) and it is telling. Especially given the fact that we have higher profits per employee than google (we know what we are doing)


>Especially given the fact that we have higher profits per employee than google (we know what we are doing)

I'm dubious of this claim. Google/Alphabet has a PPE of ~$150,000. Activision-Blizzard has a PPE of ~$33,000, EA had ~$95,000, and Ubisoft ~$15000. I think the only possible major game studios who could meet your claim are Epic or maybe Valve. Unfortunately, those numbers aren't public. So I'm going to assume you work on Steam, since Epic's new platform is likely too recent to have lots of users, and also I don't think it was competently designed.

(the other thing is that this metric isn't particularly meaningful. Google invests a huge amount in unprofitable things with the goal of profits 5 or 10 years down the line. Google devotes thousands of engineers and billions of dollars to things it knows aren't profitable. That doesn't make Google more or less competent, it just implies different priorities than one that's entirely driven by immediate returns).

>Based on my experience (currently responsible for a huge chunk of a major gaming platform, with hundreds millions users), inflexibility, emotional immaturity, inability to think outside of the box, inability to listen and admit failures, lack of emphaty, not understanding basics of sales(to sell own ideas) are major things that contribute to a bad performance reviews.

All of these are important, but they only become important once you have the baseline level of competence. If you have two equally competent people, then yes indeed the softer skills like flexibility, creativity, humility, and communication skills start to matter, and eventually they matter a lot. But those are only good things if you assume a baseline level of competence.

Consider two options. One is that you screen solely for competence. You get only competent engineers along a wide range of interpersonal/soft skills. Some can grow into leadership roles, some can't (or at least it takes longer). But even the most convincing, best "salesperson" has great engineering talent. Then the alternative: that great salesperson is a bad engineer. The ideas they promote aren't always good ones, sometimes they're bad. That's not just "not good", its actively harmful.

>Our strongest engineers will not pass google interview without preparation (me included) and it is telling.

What does it tell? You seem to be suggesting that Google is optimizing badly, and that's possible. But that is by no means the only conclusion. Here's an alternative: "The most profitable things are not always the most technically challenging". Every once in a while you'll see people on HN commenting about how they wired up a shopify store that provides some significant passive income. That's not challenging. It would take an average engineer a week to do, if that. It's still profitable. But that doesn't make you qualified to work at Google (or Valve).


Maybe there’s a problem with which computer science is being taught if it’s so difficult for so many people to derive those solutions from fundamentals, and instead have to resort to brute force pattern memorization through Cracking the Coding Interview and Leetcoding.


There are literally tv shows and contests where they do exactly this.


I don't understand your comment. Was the parent suggesting BFS (or the like) is an exceedingly difficult concept to grasp? And if we're going to claim understanding BFS is like understanding zero, then wouldn't that just mean it's just as silly to complain about a question on BFS as it is to complain about a question on zero?


Yes, my understanding is that the parent comment is complaining that since it took people with phds years to derive an algorithm for the first time, that we should never expect anyone to implement one in an interview.

But, as with a concept like 0, making the cognitive leap to understanding that there should be a way to represent the lack of something is counterintuitive (indeed, consider Tony Hoare's billion dollar mistake. The "right" way to represent the absence of an object is a hard problem). However, once you've been exposed to it, it's not particularly challenging to rederive the necessary pieces.

So yes, complaining about BFS is, imo, akin to complaining about being asked what the result of the arithmetic operation `35 - 12 - 23` is.


And it's not like it took people with PhD's years to come up with BFS. You see people make a similar argument about Dijkstra's algorithm, when he picked it as an example of a particularly easy problem to solve.


I hope you are not going to be asked to implement consensus alg on the whiteboard. Took less time to invent than 0, but good luck writing it.


I also use 0 every day. Do you use the BFS every day?


Absolutely! I don't write the algorithm every day, but I interact graphs, trees, and other such structures on a daily basis in my job, and traversing them is something that I work on. Every time I run `rm -r` for example!

I'm not asked to implement BFS every day, but the concept of a tree traversal is incredibly common.

Even more explicitly, a lot of my recent work has been involving automated refactoring tooling, so there's lots of work with abstract syntax trees and control flow graphs, which are trees or graphs, and therefore need be traversed.


Ok, here is the question for you. I’m from gaming company, so it is relevant: given a matrix of 0s and 1s where 0 is a wall and 1 is an empty space, write function that finds path between provided coordinates. It should be suitable for real time game, no gooogling. Go


I'm not clear what your point is. Sure you can come up with questions that are difficult or obscure.

Yes I can probably implement a sufficiently fast maze solving algorithm, depending on exactly the environmental constraints (for ezple, given the problem as stated I'd assume something like a* using a precomputed mat heuristic would be fast for most mazes of reasonable size, I promise either didn't google that).

But I wouldn't expect someone to answer that in an interview. Hell, I don't ask dynamic programming questions because I think they're too obscure and tricky (in the riddle way). My most common interview question involves a problem I've faced multiple times at work, has multiple valid solutions, and which I had to implement myself in various flavors before eventually coming across a relatively obscure standard library implemention.

Although before I was able to identify that implementation, I had to solve the problem 2 or 3 times, see the different flavors, and identify the common themes and the theoretical underpinnings.

I don't expect a candidate to do that without help, and most don't. But it sure sounds like you think that I'm somehow a bad engineer for asking a question that tests on the job skills I've needed, and the ability to break a problem down into component parts and implement them cleanly.

But oh no, it uses an algorithm. It's a terrible question and I should just ask a question about software engineering that doesn't use any algorithms. Because obviously people will always be able to identify the standard library implemention (no candidate I've interviewed ever has, in fact). So colore dubious of this whole argument about whiteboarding questions being a bad test.


BFS as a name isn’t a difficult concept to grasp either.


Neither BFS the concept, nor 0, the concept are particularly hard to understand. That's why I used the word "concept". If you disagree with that, I'd be interested in what you feel is exceedingly difficult about the breadth-first search algorithm to understand, or if you prefer, to explain why the time it takes to discover or first write down a concept is strongly correlated with its age.

Consider that BFS was first published in 1945, while the turing machine was published almost 10 years prior. Is BFS an implicitly more complex concept than a turing machine? That seems like a strange argument to make, but I'm certainly interested.


I share both of your concerns (while I was very lucky in getting initial experience, I know of other beginners that haven't/arent, so I'm very sympathetic.) . Started coding for work in '95.

> was I wrong then? Or am I wrong now? Perhaps both.

Neither, I think. The Algorithm interviews are bad for 90% of the positions out there, and experience matters much more than trivia, so you were right then.

And today, everyone is trying to hire "senior" (and above), so there's no concept of "will learn, lacks experience" - and the algorthm questions do badly at identify THAT, so you're right today too.

It turns out that interviewing is hard, and we don't know what works well. Most of us think "we" are the ones that can obviously see what's wrong and everyone else is interviewing poorly. Most of us are wrong.

But even besides that, we need to focus more on getting newer coders that DON'T have experience. We'll spend years looking for people that have experience...longer than it would take to grow that experience. We want seniors because we want people that will grow without being mentored, because we have far more work than people...but we skip one of the ways to reduce that workload.

I'd much rather have an interview that was teaching something new, and see how the person processed it. That's not a good interview either, but at least it is trying accomplish the correct goal.

And when we do interview for senior and above, experience will count a lot more than building a frickin' linked list.


It turns out that interviewing is hard, and we don't know what works well. Most of us think "we" are the ones that can obviously see what's wrong and everyone else is interviewing poorly. Most of us are wrong.

Cowen’s Second Law: There is a literature on everything. Hiring is no different. Why do so many of us that say “of course you shouldn’t reimplement timsort, stand on the shoulder of giants” either make up an interview process based on gut feeling or cargo cult one based on what we heard google does?


Because of Cowen's First Law: there's something wrong with everything.

So no matter if you've read the literature and implemented a process, there is something wrong with it.

That's why there threads persist. Every process has something wrong with it depending on who you are. Funnily enough everyone eventually manages to sort themselves into the right category.

The system isn't broken any more than armed conflict is broken as a way of settling disputes. It's works, it's just a little terrifying and awful.


As I see it, the difficult algorithm interviews screen for people who are motivated enough to spend 100s of hours studying for an interview, or know this stuff for some other uncommon reason. Both types are acceptable hires.


Wouldn't it be better to hire somebody who thought that was lame and who spent 100s of hours learning performance testing, new libraries, design patterns, or just working on projects?

Personally, I'd rather not work somewhere that hired based on drilling fringe information - what will the job be like? Maybe I'll feel differently in 10 or 20 years


It's interesting to me how many people value personal projects. From my personal experience, a confusing Github account with a number of small, questionable projects pushed in one commit half a year ago hurts you more than helps you. Personal projects are fine, but I think many people have the mentality of "getting a TODO app in Angular will help me waay more than implementing algorithms in C, that's useless!" which may not necessarily be true.


Fair enough, the quality of the projects matters for sure


> Wouldn't it be better to hire somebody who thought that was lame and who spent 100s of hours learning performance testing, new libraries, design patterns, or just working on projects?

I would hope so, because I do all those things and, after over a decade writing software, find the ability to solve puzzles almost completely useless for most coding I've ever done. But reality doesn't need to make sense. So, if you want to work for Google or Facebook, learn puzzles anyway :)


I really think it depends on the quality of the project. If I'm looking at a candidate, and see 3 projects, each pushed in one commit, each project has 3 classes in one package, and I see pushed compiled classes as well as source classes, that's a clear sign that this person doesn't know what he or she's doing.

That may not be necessarily a bad thing, depending on the position of course. But projects are not the be all end all, at least not in my company, and where I interviewed.


Yes you get drones and autistic savants. Great!


black pill: that's what they want


I’ll share my process:

1. The first interview must not be a technical assessment — identify shared interests, look for collaboration opportunities. You need to understand if the person in front of you will be someone you would work with for the next 10 years, their current technical skills have little to do with this.

2. At the end of the first interview, right before the logistic questions, assess how they position in the junior-senior axis — either with direct questions or by pushing them to the topic. Once you‘ve done that ask an evil surgically difficult question — the correctness of the answer is not what you‘re looking for: pay attention to how they present their (eventual) missing knowledge, or how the address the answer by giving context. A senior developer doesn’t know everything, but must know enough to manage gaps in their knowledge.

3. Search for young and talented people — search for the fire in their eyes. You want someone which, eventually, will reach goals by their own.


Search for young people? So discriminate?


I read that charitably as "give newbies a chance"


I really try hard to apply the principle of charity, but as a 67 year old developer who is still working, I'm afraid it's hard to read "search for young and talented people" without thinking of it as illegal age discrimination.

That said, I do like the interviewing approach we're replying to, other than that "y" word... :-)


Hey at least older people have laws that protect them.

Did you know that it is perfectly legal to discriminate against young people?

Yeah sucks to be them, I guess. Apparently nobody cares about discrimination against those people.

Old people are among the richest people in the world. But I guess when things are made fair, and neither young or old people are discriminated against, that appears like "discrimination" against those who are now being treated fairly.


Yeah absolutely, it was in the context of the OP.


I think the hidden agenda here might be that big corps also test for the candidate's a) motivation and b) obedience. Are you the sort of person who's willing to learn whiteboard programming on your spare time, and then tolerate abuse from the interviewers? The type of unethical business most of the big corps do works best with subservient, diligent code slingers.


Is your experience that interviewers "abuse" candidates? I interview candidates about once a week, and I always try to make them feel at ease and comfortable, no matter if they are doing well or not. I would be curious to learn about other people's experiences.


I personally have only anecdotal evidence, but I've read now many stories where the interviewers of these giants refuse to engage in a two-way, human-to-human conversation with the candidate but instead make the ordeal deliberately prolonged, stressful and unconfortable. I'd call that abuse.

Even though I'm sure there is a lot of variance between interviewers, I can't help but think that the abusive style of whiteboard grilling must "work" in that it results in able workforce, and that might be because of the reason I suggested.


> What should I choose, pytorch or keras?

I know this is off-topic, but you can't go wrong with Keras. "Deep Learning with Python" by Francois Chollet (the creator of Keras) is a Kernighan-level book. A book like this comes around once a decade (or two). If you decide to go for it though, make sure you don't follow its instructions about the amazon cloud deep learning VM's; you'll end up paying $10 per day, even if you stop the VM.


How dare you add real information to our conversation here. :)


Somewhat late question:

What would you recommend as the alternative for someone without nvidia gpu? Google colab?


I don't have a good answer to that (i.e. that I personally checked). However, FastAI lists some solutions in their latest version of the "practical deep learning for coders" course [1]. The google cloud version for example [2] was calculated to cost only about $40-$50 for the duration of their course (2 months), which is way, way better than the $10/day on AWS that I tried.

[1] https://www.fast.ai/2019/01/24/course-v3/ [2] https://course.fast.ai/start_gcp.html#budget-compute


I was aware of the fast.ai course, but not those guides.

Thank you.


Reiterating my view, I feel like the interviewing grind has become akin to gymming - you go to your mental gym, build up your 'muscles' by doing pointless repetitive tasks AKA algorithms you'd never use in real life (probably like how bodybuilders would never need to deadlift 125kgs in their daily life). It doesn't directly help you do your job but you know bodybuilders have higher than average fitness levels. So in the same manner, devs grinding leetcode probably have higher 'fitness' levels (mostly a type of muscle memory for programming) than devs who don't.


But, if I'm a scout for a football team, I don't want to see you in the gym, I want to see you play football. Maybe, ideally, I'd like to see both, but seeing you play football is by far the more important thing.


So tons of open source contribution in relevant areas with quick high-quality, low-bug-count, beautiful code check-in and demonstrated knowledge in breaking down problems into sub-problems and come up with elegant algorithsm? (something you can see in the field?)

Some analogies make sense, some probably don't map well.

Google prefers to hire Devs with strong CS foundations because they assume these Devs can contribute in many areas.

If they were only to hire someone based off something that they've done before and excel only in that area, they'd be like other companies who only hire selectively based on specific skill-set (e.g.: Java Dev, or 3D/game devs).



No competent team makes decisions based solely on the Combine. It's a data point that gets combined with college game tape, private workouts, and some other special events like the Senior Bowl. Also, a significant number of players who end up getting drafted or signed as Undrafted Free Agents don't go to the Combine.


I didn't make that assertion. I was simply pointing out that the NFL has a set of skills tests that aren't football. Further, the effectiveness of the combine is as widely debated as the effectiveness of algorithm questions.


Except lifting weight has a DIRECT affect on increasing muscle mass. Doing pointless algorithms don't have any direct affect on your coding skills. I know plenty of college grads that can memorize all sorts of algorithms, but are shit at real world code. If I'm a company hiring to do REAL WORLD CODE, I'm going to ask questions pertaining to the position I'm willing to fill. The problem with these companies, is that they are hiring more than they need, therefore they aren't asking questions pertaining to any REAL job they're looking to fill.


It is also a form of “proof of work”. If you are willing to go to the lengths of learning these things, maybe you’ll be able to learn other things that are harder to assess during an interview.


In that case, we should just get candidates to weave wicker baskets.


Honestly, there are so many posts like yours on HN, it's a surprise companies don't change this ridiculous algorithms thing. Hiring managers here complain that candidates all lie and they need to weed them out. However, algorithms bias towards younger people, recently out of college, math hobbyists and people with a lot of free time.

Me, I tell them in the first phone screen, "I'm a Systems/DevOps guy, I don't do algorithms and whatnot so I'm just letting you know in advance in case you ask me to whiteboard something like that." So far I was only spurned once out of half a dozen screens employing this statement.

If you want to screen liars, there are a million ways to do it. Truth is, folks, most interviewers don't read resumes in depth, and they're not clever enough to interview for honesty.


I’m a software developer first and foremost, I am a software architect second these days specializing in building stuff on top of AWS.

But I might try to do some algorithm type interview, but wouldn’t feel bad if I bombed it. In fact, the only algorithm type interview I have done in the last 10 years, they made me an offer but I declined it for another job that asked more architectural questions.

The way I see it, if I could write 65C02 and x86 assembly language programs in the 80s, I think I can handle the needs of your software as a service CRUD app.


As a hiring manager I would be impressed by your background. Unfortunately most will never read that far back. Or worse, not have enough experience to understand someone who can do that can handle the needs of their software as a service CRUD app.


There's really no need to screen for liars. Generally speaking, I'll try to ascertain how the candidate represents the skills on their resume. Some represent their skills well and can describe in detail their approach to solving a problem or some such. From there, it's not hard to assess things like passion, determination, etc.

Usually, I'm just looking for one thing the candidate does well. There's really not much room for lying and if they claim to have some crucial skill and then I discover after the fact that they don't, that's grounds for dismissal.


This all comes down to what the company is optimizing for.

Everybody here seems to assume they are trying to filter for the good candidates...but what they are actually trying to do with these kind of interviews is filter out the bad ones!

Because the damage when hiring a bad candidate is much higher than the damage from missing out on a good one!


> Because the damage when hiring a bad candidate is much higher than the damage from missing out on a good one!

I get that this is the conventional wisdom in a subset of this industry, but in my experience this "truth" does not have as much objective support as the people who keep repeating it think it does.


In at least one aspect, the adage becomes facially untrue -- you can fire bad employees, but you cannot get back good candidates rejected by means of a degrading exercise. You probably lose them forever.

In companies where opportunity cost and hidden losses are nobody's responsibility, this sort of mediocrity is well accepted.


You can fire the bad ones, sure. After you document everything and cross i's and dot t's. Even if you don't CYA, you still lost team productivity while they onboarded the new person, and that time is lost. Plus the hit to team moral, and possible negative affects to team culture of dealing with an under performer or toxic individual.


What's the cost to team morale when the team members have to put in extra time to meet deadlines because the team is shorthanded? What's the cost to the company when the team doesn't have the bandwidth to take on work and projects start slipping? How does team culture fare when someone on the team always finds some reason to reject every candidate they see, and this continues for weeks or months on end? What is the loss of productivity from having to conduct all these extra interviews until just the right person walks through the door?

The answers to both sets of questions are very situational, yet some people treat them as if they have universal answers.


> What's the cost to team morale when the team members have to put in extra time to

Less than the cost of being perpetually afraid of being fired.

If an engineer on my team got fired, no matter how much they deserved it, I'd probably start looking for a new job or team immediately.

The fear of being let go isnt something I'd ever want to deal with.


Just to be clear the kind of strategy we discuss here only works at FANG like companies that have enough candidates applying so that missing a good one doesn’t hurt their hiring goals.

Of course it sucks for the individual...but such is life


At FANG good candidates tend to apply again a year or so later


Truth, and also especially so for a company like FB or Google where they probably have an abundance of qualified applicants, for a variety of reasons. For most companies, copying what FB or Google (or Microsoft or whoever) is doing, is probably a bad idea, in tech interviewing or many other things.


Nope. They're neither filtering in good ones or filtering out bad ones. They're filtering for people who find a way to hit whatever arbitrary metric the Company sets up as "success", and these people will have many more chances to practice this "skill" in subsequent self reviews and metrics hacking. They also end up running the Company and hiring more like themselves.


As someone recently interviewing I targeted roles where I didn't have to jump through these hoops and it worked out fine. Contacting people I had worked with before who could vouch for me made it much easier to land a job.

The top companies with these leetcode tests probably don't care that good people being rejected or avoiding them because of the amount of preparation required. Middle sized companies and startups doing leetcode tests are missing good people and probably can't afford the same number of false negatives as someone like Google with an endless supply of candidates.

I would much rather spend a weekend doing a take home test and showing how I actually work than being asked to write irrelevant code on a whiteboard. I think leetcode style interviewing is driven by time constraints of the interviewer and some more effort and thought needs to be put in on how to choose people based on the specifics of the actual role they are hiring for.


I'm in a similar situation.

I think the counterargument might be that at our age, you should have a network of people who will hire you just based on your stellar performance on previous jobs, if you're that experienced and sophisticated.

If you somehow don't, well, maybe you need to brush up on your tree balancing skills...


I believe for older engineers who regularly read these threads, this is the comment. Wish it weren’t true, but it is.


I wrote a custom HashMap for Java, used BFS and DBS on graphs, wrote a top down custom parser, custom string searching algorithms to solve real business problems. I would rather work with someone who knows how neural networks really work rather than who knows pytorch or keras, because they can be learned rather easily. In some industries knowledge of algorithms can be more valuable than knowing a myriad of frameworks that change every few years any way.


> In some industries knowledge of algorithms can be more valuable than knowing a myriad of frameworks that change every few years any way.

This is exceedingly rare... so you wrote a HashMap implementation in Java?? None of the custom maps discussed [here](http://java-performance.info/hashmap-overview-jdk-fastutil-g...) were enough? It must be a really rare problem you're working on if there's no library that provides an acceptable solution for it in Java.

> I would rather work with someone who knows how neural networks really work rather than who knows pytorch or keras

I would rather work with someone who knows general programming (which is not the same as algorithms - there's so much more to it!) and software design... but if working on a product that uses a framework heavily, good knowledge of that framework can be the difference between getting things done in minutes VS weeks (of painful and time-consuming battling with the framework to do thing the way you think they should be done, rather than how it's done within the framework).


I agree that these problems are rare, but they do come up, at least they did in my experience. As you alluded general programming and software design is not the same as knowing how a particular framework works. The former is much more valuable, but at the same time if someone is able to understand in depth a complex technology/framework he/she is most likely great at general programming and software design.


There are people who really know how NN work? I thought there were only people who know how to implement them ;)


You right, but I would say we do know how artificial NN work, because we are able to construct them, but we don't actually know why they work ;)


You're not wrong, but that one time you see a place for a new algorithm for a specialized problem can make a big enough difference to be worth it. If nobody in your group has the range, it's not likely you'll know when it'll pay to call in the research department with the PhDs exactly when they're needed, either. There's no bright line between coding and invention.

More mundanely, when I was starting out at a small shop (I'm around your age) my coworkers hadn't mastered undergrad algorithms, and it made a significant difference in what we could do.

It's unfortunate that attempting to test for this seems to have encouraged too much memorizing of known tricks relative to better mastery of principles.


How would you go about mastering the principles rather than practicing random algorithmic challenges?


Udi Manber's Algorithms: A Creative Approach looks like a promising book to work through. There are lots of great resources that didn't exist when I was an undergrad.

But how do you approach them? What prompted my comment was all the times people comment online about "memorizing algorithms" to prepare for interviews -- learning about algorithms will include a lot of them sticking in memory, yes, but approaching it as cramming a textbook into memory the way students cram for a final exam seems... disappointing.


> Much more important is to have the experience of how code complexity accumulates, and how to mitigate that.

That's so right. But that is experience, so I think when you know most the candidates don't have it, you end up looking for other stuff to test, and then your interview process gets infected, and eventually when you are interviewing for positions that should have experience, you get a lot of the same bullshit questions.

There are plenty of stories here of novice programmers doing some passion project, and 6-12 months after learning to program they are busting out some fairly complex algorithms that to someone that took the long route of getting a CS degree can look somewhat amazing, and frankly, humbling. But I think what's going on is that's the easy stuff to get a hold of, because all it takes is some judicious googling, or more likely, asking some professionals from help, and you're pointed in the right direction for the tool that solves your need, so you use it. Getting amazing progress on a new project isn't really hard.

Getting sustained progress, or being able to fix your problem a year or two in once you realize a major architectural change is required, and not being bogged down for months and losing interest, those are amazing, and those take experience or constant mentoring to achieve usually.

Or maybe I'm just projecting what I currently value.


Algorithm interviews are good for people that will be writing algorithms. Most of us are just plumbers, even so a solid knowledge about what algorithms are available and what their strengths and weaknesses are is as important as good knowledge about the tools is to plumbers.


This is my main beef with tech interviews: you get given a test, or an algorithm, or put under the spotlight in a pairing session to solve a problem in essentially the least efficient way possible. It's usually under the guise of seeing how you think, but it's pretty damn hard to do that without also judging how the code looks and how much you were able to write.

This then becomes representative of your experience in spite of that fact that you are never likely to be confronted with that kind of problem with that kind of timeframe. Whatever's on your CV, and whatever you can say about what you've learned over the years, becomes totally irrelevant in the face of that.

I think it's offensive and I don't like how the industry has standardised on basically assuming everyone's a bullshitter. What's worse is that you'll have to repeat this over and over again for any company you interview with.

To that extent I'd much rather see the formation of a professional body that offers a trustworthy credential, potentially one that you need to renew every couple of years to ensure you're still current. That comes with challenges of its own but I'd rather have something that is both verifiable and can be reused.


>This then becomes representative of your experience... Whatever's on your CV, and whatever you can say about what you've learned over the years, becomes totally irrelevant in the face of that.

Don't think this is true. At most tech interviews, the algorithms portion is more of a technical bar. It's usually the CV, years of relevant experience, and performance on the architecture/system design interview that determines what leveling you are.

>To that extent I'd much rather see the formation of a professional body that offers a trustworthy credential

Every company values different things from their candidates, so I don't think a formal interview process will ever go away. That said, there are companies like Triplebyte that try and standardize the interview process - they usually don't ask algorithm questions either. It's not quite a certification, but they'll fast-forward you through the interview process at companies that use them.


> I feel annoyed that all of these stories of interviews involve asking questions about algorithms that rarely come up in real coding, and if they do you should NOT be rolling your own code

I completely disagree with you, because how do you define rare. In my case as a JavaScript developer many cases commonly considered rare are in fact exceedingly common and important, but considered rare due to tooling and people hiding from them. When the reality is invented here syndrome every problem is either a configuration or rare. I make it an important point to attempt to discover this distinction when I am interviewing for a new position or interviewing new candidates.

I have often seen weak developers promoted to senior because they are good with tools, trends, and configurations only to struggle in the face of an original problem. You can't simply hope to download your way out of every development problem and hope to be taken seriously as a senior. That reality is something many people are unwilling to accept at great emotional peril.

https://en.wikipedia.org/wiki/Invented_here


There are career stages. For candidates just out of school or with little experience asking algorithmic questions totally makes sense. For more senior candidates (who actually progressed to the next stage, not just spent a lot of years), the questions become more real-life, more open ended and with more than one (or sometimes none) “correct” answer


Are algorithm puzzles really that ubiquitous in the US?

In the UK I've interviewed at dozens of companies and never once been asked to code a breadth first search or something like that. Nor have I ever heard of a developer being asked to solve such things in interviews over here.


Usually larger tech companies that are flooded with applicants tend to ask these more.


I might be wrong but I don't think that larger tech companies get that many more applicants for jobs than smaller companies do. Beyond FAANG I don't think there is really much more "status" around working for a large company vs working for small company. Most people understand that just because the company you work for is large one doesn't mean your job is any more challenging or technically advanced than it as at a small company.

Also a company hiring a mid-level developer (say around 3 years experience) doesn't really have that much of a pool to chose from. Most good developers are already in jobs and pickings are slim, its a buyers market.


Larger companies usually have more brand recognition == more applicants. Many smaller companies are essentially unknown to the public and need to rely much more on talent agencies to bring in applicants.


What do they ask in the UK?


In my experience they typically ask you questions about the experience you've listed on your CV. If you say you have experience working with AWS, then they might ask you something like "explain what a VPC is and why is it useful?". Other more general questions are usually along the lines of "tell me about a solution to a problem you solved and how you designed the solution to that problem".

The few times that I've been asked very specific technical questions they have always been related to the job I was applying for. Example: a ruby on rails job interview I was shown a few ActiveRecord models and asked what is wrong with them and how I would improve them - the answer was that they were all really polymorphic models but that was not how they were implemented in the code. Or for a frontend role, they might ask you "explain the javascript prototype chain to me".

Again, in my experience, its always seemed like the interview was more of a personal test rather than a technical one. Will the person be easy to work with? Will they be communicative or will they bottle up their issues and resent the team for it. Are they willing to learn? Will they be able to hande occasional pressure and stress? I think its generally accepted that its extremely difficult to accurately gauge a person's technical abilities in an interview. Also employees always start on a probationary contract in which they can be fired with 1-2 weeks notice, this usually lasts between 3-6 months, so if it turns out the employee was blagging it in the interview then it will become apparent pretty quickly and they will likely not make it past the probation period.


This sounds similar to Russia, at least to me with my limited experience as an interviewer and even more limited as an interviewee.


I have interviewed in the UK and did algorithm whiteboarding, so I'd say it's company-specific, rather than country-specific.


It's not much different in the UK if you apply to FAANG, hedge fund, or a cargo culting startup.


You are absolute right. I’m telling recruiters upfront that I will spend 0 time preparing and if it is a deal breaker - it is what it is.


You are so right. Im 55 now and have developed on tools, a lot of ERP/Manufacturing stuff, compliance, integration tools. Have never had the need to reach for Knuth so that shows either I am pig-ignorant, arrogant, or there is no real need in general. It is good to know algorithms but these are not the main stuff of the real world. Learn about design patterns, user experience, product philosophy, and invest time in learning about your company (who, how and why started, markets, competition) and you will go further and faster than being able to ace a whiteboard interview on the foibles of event processing in Vue. And yes i still cant write good javascript - because IT IS NOT IMPORTANT so i have avoided until this year and Im now learning it as a hobby, not a need.


While I agree with you on the non-algorithmic coding skill being more important in most of the scenarios that an coder deals with at work, I feel having basic understanding of algorithmic skill is important as well for coder success. Interview should test basic algo skills along with other important skills, but when I put myself in interviewers shoe I realize how difficult its is to test on real coding challenges as every company has its own sets of tools and techniques that they use and prefer. Testing it would require first detailing coder on companies present tech culture which is a difficult for a code to get in short duration.


As someone who is interviewing for internships, I view all of these algorithms interviews as a necessary evil. While they may not reflect the day to day job demands of programming, they are certainly easier to measure and serve as a benchmark for candidates.

Not all of them are bad though; I had an interview that had me implement a basic data structure in accordance to the specifications given. It didn’t require memorization, practice, or any “Leetcode grinding” — only fundamentals in communication and programming. The time I had was about an hour so this is definitely a plausible substitute.


Ex Amazon here. We never asked silly puzzle questions, but asking questions about algorithmic complexity paid off when hiring strong, senior engineers.

> Much more important is to have the experience of how code complexity accumulates, and how to mitigate that

That's part of the reason. The average developer knows how to pick a popular library and throw code at it until it works. When entire teams do that you end up with endless complexity.

That's why Google and Amazon are known for [re]inventing their own solutions.


> I cannot spend hours and hours studying up on these algorithms, there are much more important things (real coding-related things) which I need to learn about, to the extent I have time to do that.

Are "real code-related things" really much more important if it only takes hours and hours to learn something that might get you an offer at one of these companies?

Perhaps those hours and hours are actually far more valuable 'financially' speaking than a lifetime of studying code that is valuable 'technically' speaking. I don't doubt that some of the big name companies use rarely-used algorithms with battle-tested solutions on purpose JUST to see if you prepared for battle. They look for non-technical smarts because they have no shortage of technically prodigious applicants.

At Google, with over 400 applicants for every position, they have no shortage of technically-competent engineers. They look for people who think way outside the box and try new things, sometimes resulting in industry defining inventiveness. It's ~10 times harder to get hired at Google than get into Harvard.

https://www.forbes.com/sites/stanphelps/2014/08/05/cracking-...


Reminds me of the old phrase, re: academia: "The competition is so high because the stakes are so low." There is something really weird, at least to me, in working so extraordinarily hard to prove yourself worthy of serving someone/some company. But that's just me.


Money and prestige my friend.


Money, I can understand. Under bayesian analysis, your better off going into medical studies, though. Prestige...well... In my dads day, working at IBM would've earned great prestige. On graduation day for me, working at Microsoft would have earned prestige the same year Google incorporated. So...fuck prestige.


The easiest way to get hired at Google is to let them come to you, not to directly apply


The Field of Dreams approach. "If you build it, they will come"


Really, that's not far from the truth. If you've worked at other well known "good" companies and worked on hot/important stuff, and that info is on linkedin, you will probably get approached by a google recruiter at some point. And unless you fuck up your call with them to make sure you're interested and a real person, that basically guarantees you a first round technical phone screen, which is the hardest part of getting hired at Google. You can study as much as you want and be the best engineer possible, but that won't matter if you don't get to the first round interview.

You basically "build" a linkedin profile that comes up when recruiters search for technically hot things, and then they will come knocking


Does this method still bypass the algorithms interview? It seems like it only gets your foot in the door, which is probably the harder part for most.


Unless someone inside Google wants you that _bad_, you can't by-pass the interview session.


yes, bypasssing the int4erview is hard, what I'm saying is that you can go directly to the first round of technicals without hazards if you play it well


I found essentially most 'algorithms' code is just terrible code. A lot of people spent a lot of time learning algorithms other than more broad techniques write terrible code every day.

An alias for so-called 'algorithms' is 'imperative style' for 'functional programming style', or 'procedural programming' for 'object-oriented programming'.

They are too arcane to read, hard to modify and error-prone. Most of them require mutable data structures, intermediate snapshot for a special optimization purpose, make everything much harder to reuse.

It mostly requires you to instruct every piece of code, every step of execution. Instead of just describing what you need, and let the code find a way to fulfill it autonomously, in a declarative manner like Haskell or Prolog.

And 99% of software companies do not really have the need of requiring their employees having a deep grasp of algorithms, while most of them need their code somehow more maintainable. Those of the Leetcode oriented interviews are just really bad.

Personally, I believe business sense and culture stuff are very important. As for skill part, a lot of concepts could be more useful than algorithms like understanding of domain and relation modeling, immutable data structures, lazy evaluation, reactive design etc.


Even if if you don't roll your own code, knowing how it works is still important. I see cargos cult code far too often.

Granted that you only need a vague idea about the algorithm. But going from a vague idea to working code is also a valuable skill.


Have you considered that they aren’t necessarily looking for a particular answer or even a correct answer but rather your thought process while working through problems and how you engage with a peer?


Sadly they are looking for the most precise and optimum answer (at least at FB they do)


I feel exactly the same.


> If it’s of any use: I was interviewing for my second job out of college with about two and a half years of experience without any particularly notable internships or employers on my resume; I went to a very small school that had zero known software companies at their “career fair”; I started preparing in late April and started applying in June/July; and, lastly, a few months in, my job is everything I could have possibly dreamed of.

Wow, that’s amazing! Congratulations to the author because this demonstrates they have genuine talent.

In contrast, I’ve been a programmer for 10+ years, and I cannot pass the technical interviews in the companies mentioned above. At first, I thought the reason behind my failures was a lack of formal education in Computer Science, so I started reading more books. Then I thought, maybe it’s the fact that I spend more of my “productive” hours in my job just doing lumberjack web development, so I started participating in competitive programming (LeetCode, Code Golf, HackerRank, Code Wars, among many others).

Finally, I realized my brain needs more time than the average programmer to find patterns in this type of problems.

I gave up on my goal to land a job in one of these big corporations.

However, I don’t feel bad about giving up, in fact, thanks to all these books and competitive coding exercises, I was able to find two of the most exciting jobs I ever thought I would have, for 4+ years I worked in the software security industry doing Malware Research and building infrastructure tools for other security researchers. Most recently, I entered the game industry, and finally, I can use my algorithms and data structures for non-trivial projects.

Interestingly, I’ve been recently getting more messages by recruiters who want me to work for some of these companies. I politely decline the invitations because I know I cannot pass the technical interviews, but I promptly refer to some of my colleagues because I can see my younger self reflected in them, and I want them to have the experience that I couldn’t have to work for one of these companies. Even if they work only for a few months, as many people burn out, having the company’s name in their resume will grant them dozens of new opportunities.


I cannot help but think that these big tech companies (FAANG, et. al) are missing out on diversifying and increasing their engineering expertise by passing over developers like you.

I often think what would Google/Facebook would be like if they hired in some experienced engineers that may not be able to whiteboard a BFS tree or can tell you Djikstra's algorithm, but have proven business track records of getting projects done, on budget, and on time. Real, pragmatic, get-it-done types of engineers. (That's not to say whiteboard expert engineers can't also be this way - it's just that whiteboard interviews don't hire for this in particular - technical expertise comes first)

There was an excellent comment on another thread yesterday (that I can't find) that basically said something along the lines of "If I'm asked about BFS trees in an interview I'm going to tell them I'm just going to google a library that can handle it - I've got more important work to get done"


The technical interviewing scheme is not great, but I haven't seen another system that works.

> I cannot help but think that these big tech companies (FAANG, et. al) are missing out on diversifying and increasing their engineering expertise by passing over developers like you.

I think this is certainly true.

> I often think what would Google/Facebook would be like if they hired in some experienced engineers that may not be able to whiteboard a BFS tree or can tell you Djikstra's algorithm, but have proven business track records of getting projects done, on budget, and on time.

Well... how do we find these people? By looking at their resumes where they claim this? By contacting references who will attest to it? By trusting the intuition of subjective evaluators of the candidates?

Practically speaking, FAANG companies do hire such individuals, they just do it through acqui-hires. If a person works at a company that is good enough to be worth acquiring, then we have a good signal that they are effective employees even absent a direct evaluation of their technical abilities.


> Practically speaking, FAANG companies do hire such individuals, they just do it through acqui-hires.

there's a huge pool of employees that are in companies which aren't potential acquisition targets.

> Well... how do we find these people? By looking at their resumes where they claim this? By contacting references who will attest to it?

internal references? if you've got a couple of internal folks who are doing good work, and they all worked with and vouch for old bob, maybe that's better than anything you're going to find out from <8 hours of whiteboard scribblings?

> By trusting the intuition of subjective evaluators of the candidates?

even the faintest whiff of implication that FAANG interviews might not be subjective is hilarious.


I've had internal referrals at a few FAANG myself, I have one of the "unique" (no degree, some high school, ops/coding since 12 so about 15 years on/off) backgrounds and the people who referred me would be on the team that I'd be joining and all seemed incredibly excited to get me on board. I work on FOSS projects with them already.

At each place it was people from other teams completely unrelated to that team who interviewed (or would interview) me and eventually turned into a decision panel where everything about me would be considered by these people who really knew nothing of my character/skills aside from the resume and white boarding.

Between that and the amount of times I heard "Stanford" tossed around in a way that put down other schools (while not having a degree at all myself) I decided to give up on ever working at any of these places without being an acquihire. It just seems like a far fetched pipe-dream and I'd never check the required boxes that they expect for someone to sit in the same building with them. And honestly, none of that sat well with me.

It was an interesting time and I got to finally experience SV and realized it's likely not a place for someone like me.


I work for Google, opinions are my own.

First of all it sounds like your interview experience was unpleasant so if this was at Google I apologize.

Secondly, I can totally relate to feeling like I don't belong having also come from a nontraditional background (No college degree).

> At each place it was people from other teams completely unrelated to that team who interviewed (or would interview) me and eventually turned into a decision panel where everything about me would be considered by these people who really knew nothing of my character/skills aside from the resume and white boarding.

This sounds similar to what we do at Google; people who know you actually aren't allowed to interview you because they will be biased. We try to make the interview as objective as possible. Note that information from anyone who knows you or referred you will be shown to the hiring committee though so it's not as though that feedback is not used.

> Between that and the amount of times I heard "Stanford" tossed around in a way that put down other schools (while not having a degree at all myself) I decided to give up on ever working at any of these places without being an acquihire. It just seems like a far fetched pipe-dream and I'd never check the required boxes that they expect for someone to sit in the same building with them. And honestly, none of that sat well with me.

I understand why you feel this way but that's definitely not true! I don't think you necessarily should want to work in FAANG but I strongly think you should believe you are capable.


One of my recent FAANG interviews was ENTIRELY whiteboarding. It kind of shocked me.

It's weird that it's that skill, and only that skill, that gets evaluated. I did another interview at a different one where there was at least a design interview (though I flubbed it and wound up being incoherent).

It really feels like they aren't even trying to evaluate anything other than whiteboard coding. Accepting that it's not a great signal and yet fully investing in it.

It's such a weird skill and it's so easy to perform badly; I'd be kind of shocked if the test/retest validity wasn't very low.

Also... I mentioned that working on teams with other women was important to me... but every technical onsite I've had has been given by a man. They've pitched teams led by women, and my HR/recruiting contacts have been nearly all women. But for the interview itself? All men.


Trust me, companies would love to have at least one woman on every interview slate, and not just for women candidates. The problem is that the ratio of women engineers at the FAANG companies is such that this would put an incredibly unfair burden on women engineers. They would have to spend all of their time interviewing, or at the very least a disproportionate amount of time.


>I'd be kind of shocked if the test/retest validity wasn't very low.

It's absolutely very low, and they're okay with that. One of the things recruiters at these companies will tell you if you get rejected is some variant of, "Don't worry, you can always try next year." These companies fully understand that they're rejecting good engineers. They don't care, because, historically, the number of engineers applying has been so high that they could reject 75% of the good engineers and still have enough to fill their headcount.

We'll see how that attitude towards interviewing changes when high Bay Area/Seattle housing prices make it more difficult for them to recruit.


> internal references? if you've got a couple of internal folks who are doing good work, and they all worked with and vouch for old bob, maybe that's better than anything you're going to find out from <8 hours of whiteboard scribblings?

At big companies this is hard to scale because you have to protect against nepotism at the top layer. This forces policies protecting against the bad outcome.

At small companies this does happen.


Provided references are at the core the worst way to judge if someone can do the job and the laziest way. If you want to rely on references you have to get them yourself through background check or the risk of gamification is huge.

Get a sense of the projects they have worked on if those skills relate to the position. Make a decision based on that.

Random coding tests, whiteboarding, buzzword dropping are only helpful to a point.


Good points - provided references are shit, simply because they can be gamed. If you work for me and I dislike you but don't have the courage to pull out the fire hammer, I can give you a great reference. If I really like you because you're extremely good (and make me look good), I can give you a horrible reference and hold onto you.

However, OP was talking about internal references. This would be a situation where I work at Company A, but I know you and trust your work. Therefore, I refer you to Company A, big up you a little and suggest that they pursue hiring you.

The difference is that if you suck, it reflects poorly on me (and quite likely kills my dreams of upward mobility). Normal provides references don't have the same motive to be truthful!


What? Is this just conjecture? If you give a bad reference to an employee you are directly putting you and the company in harm's way in terms of litigation. Usually, you just don't give a reference other than confirming tenure existence and duration if you won't go into positive detail.


That's a textbook answer, but in actual practice, the probability of litigation is extremely low.


Many acqui hires get interviewed again. Most acqui hires are a business deal for the company's business.


Does any other company than Google interview acqui-hires?

I’ve never heard of any other company doing this, but I haven’t been looking especially carefully.


Every company I've worked for interviews acquihires.

From FAANG, to start ups, to established traditional engineering companies.


Which of the FAANG specifically have you experienced acquihire technical interviews at?

Just curious, because again, I’ve only ever heard this from friends that got bought by Google. I’m not saying others don’t, just haven’t heard of it from folks getting acquired at other places.


How is it an acquihire if the company is interviewing all the talent they acquired anyway?


- You are getting paid to interview

- If they decline, you usually get a very generous severence package

- While sometimes technical, there is usually significantly evidence of your abilities from the acquired company's records.

- In my experience it's usually a cultural test more than any other.

- Interviewing is part of the evaluation. If the hiring company thinks everyone is grossly incompetent they can reevaluate the acquisition or call it off entirely.


Not all of it, but some of the force does to ensure that they meet the bar of the hiring company and also to get calibrated in the eng ladder.


This is correct.


> Well... how do we find these people? By looking at their resumes where they claim this? By contacting references who will attest to it? By trusting the intuition of subjective evaluators of the candidates?

While not perfect I wonder if a person's projects are a good signal for this. There certainly are those who have developed a significant open source project but who get rejected by the FAANG companies, the author of Homebrew being a recent infamous example.


One unfortunate side effect of being at a FAANG company is that most of your best work is probably proprietary and you will never have the chance to show it to anyone outside the company, nor will you have much free time for personal projects.

As an interviewer, I can definitely say that GitHub has become a bigger part of helping to evaluate people.


> As an interviewer, I can definitely say that GitHub has become a bigger part of helping to evaluate people.

Many people can’t work on open source, either due to a lack of time or corporate policy.


Every time the interview story of the guy behind Homebrew gets brought up, there’s the reminder that he interviewed for a software engineering position while he would’ve been better suited for a product manager position — he also mentions this as such.


The author of Homebrew was rejected for software engineering at Google, which was perfectly reasonable given what he has said about his own skills. He has demonstrated very good product management aptitude on the other hand; it would be far more concerning if he were rejected from a PM role.


> he has demonstrated very good product management aptitude on the other hand

Not to diminish his accomplishment... he could be a good candidate for PM but his tool is more of a dev-tool (so I suppose this is a niche-ish?)


In Howell's own words from https://www.quora.com/Whats-the-logic-behind-Google-rejectin...:

> I wrote a simple package manager. Anyone could write one. And in fact mine is pretty bad. It doesn't do dependency management properly. It doesn’t handle edge case behavior well. It isn’t well tested.


From later in his same post...

But ultimately, should Google have hired me? Yes, absolutely yes. I am often a dick, I am often difficult, I often don’t know computer science, but. BUT. I make really good things, maybe they aren't perfect, but people really like them. Surely, surely Google could have used that.


> I am often difficult, I often don’t know computer science, but. BUT. I make really good things

Having worked with people who are dicks but make really good things...I wouldn't want him on my team either. There are plenty of people who make really good things and aren't dicks.


Gotta agree. People sometimes underestimate the power of actually getting along with others!


> There certainly are those who have developed a significant open source project but who get rejected by the FAANG companies, the author of Homebrew being a recent infamous example.

It’s always possible that Google felt he wasn’t what they needed. And keep in mind that Howell ended up being hired by Apple and working there for a while.


>By looking at their resumes where they claim this? By contacting references who will attest to it? By trusting the intuition of subjective evaluators of the candidates?

I mean... Yes?

This system, backed by "trusted recommenders" is exactly what academia uses, and they seem perfectly capable of discovering Higgs Bosons and whatnot.


They physics communinity does not seem to have the issue of being able to judge merit from resumes. When you see a physics PhD with a list of academic references, chances are that the person knows what they are doing; with computer science it’s somehow likely that the person might not know their way around the command line or when using an array might be a bad idea…


Ironic example, as the guy who theorized the Higgs Boson originally doesn't think he'd be productive enough for today's environment. https://www.theguardian.com/science/2013/dec/06/peter-higgs-...


"intuition of subjective evaluators of the candidates"

This is inherently biased and proven to be the worst way to hire people.


>The technical interviewing scheme is not great, but I haven't seen another system that works.

I would argue that pair programming or take home projects do a far better job than the standard Whiteboard Algo interviews. In fact I don't think it's even close but SV engineers have been captured by this Whiteboard Interview Stockholm Syndrome/Hazing and continue to perpetuate the insane idea that there is no better way.


Many people on HN also complain about "I don't have time for pair programming, take home". They don't like interviews. People just expect to be paid top dollar on their word.


> Many people on HN also complain about "I don't have time for pair programming

How does one not have time for pair programming? It's the exact same time commitment, from both the interviewer and interviewee, as a whiteboarding session. It's just a different format for the interview.


This is probably the only part I'll give you as far as your comments on this thread, but even this is inane and you're projecting. First of all, the problems with take home tests are the time commitment, which I can understand with the caveat that you do a lengthy pair programming exercise in person. I haven't heard that many complaints about pair programming, but I'm sure I exist so I'll give you that.

I don't think it's the case that people don't like interviews. I think you're making a strawman. I'm not going to go and say that you're part of the cycle of SV engineer being hazed, reproducing it and exhibiting a sunken cost fallacy/bias towards the way you've done it, but it's possible. I don't think this is the ideal way to interview.

What's more, I've been seeing actual improvement on the state of the art in this area. Platforms like Karat et al (not sure if Karat is the best in this area but I did have a good experience with a company that used them and interviewed me well) are actually incentivized to minimize false positives and negatives rather than just one. You might be surprised at how much better a good technical interviewer can be than an average strong engineer.


Please provide a rebuttal on the comments individually if you care to disagree. This comment was just alluding that any technique is ever good enough for HN. People just want word of mouth and their resumes to be enough. That doesn't work when resumes lie.


> People just expect to be paid top dollar on their word.

And their education, previous employment, etc.

No one makes a neuro-surgeon perform a surgery before hiring them.


> No one makes a neuro-surgeon perform a surgery before hiring them.

True, but I also know that a neurosurgeon graduated from an accredited school, did an internship at an accredited hospital, and then passed a standardized licensing exam.

If we had that for engineers we wouldn't need to test their skills either.

When I was doing hiring, I would see resumes of people with 10+ years of experience who couldn't write a simple loop in their favorite language. If you've been coding for 10 years, you should be able to write a simple loop. That's the problem we're solving for here.


An engineer that did 4 years of college at an accredited engineering school isn't enough?

What you are asking for, is a surgeon to retake the boards every time they change hospitals. Or a licensed professional engineer to retake the PE exam everytime they change jobs.

The algorithms asked in interviews are rarely implemented in a job. All they prove is how much you studied and the author of the article proves that.

What our industry is missing, IMHO is required certification and training. Doctors and nurses have yearly training and related exams to keep their certification. That's why a hospital can hire staff based on a license...Not becsuse the items you mentioned. But our industry would never go that route, which is a longer rant.

Also if peope who can't write for loops are passing your phone screen... You might want to update your phone screen.


> Or a licensed professional engineer to retake the PE exam everytime they change jobs.

Yes, just as you retake your driving exams every five years, you should retake your engineering exams (unless you are an accredited engineering instructor, in which case the license becomes permanent) every ten years.


> just as you retake your driving exams every five years

Uhh... I haven't taken a driving test in 17 years (and two states ago, to boot).


> When I was doing hiring, I would see resumes of people with 10+ years of experience who couldn't write a simple loop in their favorite language. If you've been coding for 10 years, you should be able to write a simple loop. That's the problem we're solving for here.

While I agree with this, the FAANG interviews take it too far. Simple fizzbuzz is enough to weed out these completely incompetent engineers. If they pass that, accomplishments and experience are going to be a much better indicator of engineering ability imo.


> If you've been coding for 10 years, you should be able to write a simple loop. That's the problem we're solving for here.

That's the problem some interviews solve for. FAANG interviews take it to another level.


When everybody can solve a simple loop, a base bar, then the bar has to be raised.

The bar is being raised all the time as much as it is painful and hard for me to see/experience this :(.


> If we had that for engineers we wouldn't need to test their skills either.

We have that for "real" engineers. Doesn't stop many of them from being atrocious at their job. Doesn't stop doctors either, for that matter.


> True, but I also know that a neurosurgeon graduated from an accredited school, did an internship at an accredited hospital, and then passed a standardized licensing exam.

...and meets ongoing continuing education requirements.

> If we had that for engineers we wouldn't need to test their skills either.

We do have that for professional engineers.

We don't have it for people working in software whose job titles have become (but largely weren't for similar roles a few decades ago) "engineer".


> ...and meets ongoing continuing education requirements.

Which are a joke. Attending conferences and weekend workshops take care of this.


> Which are a joke

Sure, professional licensing provides fairly weak guarantees, but it's more than exist in software, hence FizzBuzz.


> If we had that for engineers we wouldn't need to test their skills either.

I think we will, eventually. Other fields of engineering already do, of course. Software is new and not that many people have been killed by bad software (unlike bad buildings), but I think we'll get there.


> And their education, previous employment, etc.

Unfortunately, this seems to be poorly correlated with whether people can actually code.


Actually it seems like motor skills are a part of neuro-surgeon evaluation - https://www.bmj.com/content/355/bmj.i5976

There is also an experimental virtual surgery simulator for objective evaluation - https://www.ncbi.nlm.nih.gov/pubmed/26153114


> I would argue that pair programming

Google allows you to write code on a Chromebook instead of a whiteboard (don't know if it's for everyone or some people). Is that pair programming? Or do you mean actually working with your preferred IDE/text editor, terminal, browser to look stuff up?


These processes are optimized to reduce false positives not false negatives. So they already know that they might be missing on some great developers.


This is the correct explanation; false positives are so much more expensive than the opportunity cost of a false negative.


You think people that pass technical interviews can’t be false positives?

I think they weed out a few, but completely ignore practical development skills, work ethic, soft skills, design and architecture skills, etc.

Of course maybe this explains why most of the big tech companies have seemed pretty stagnant for the last decade, largely failing with products and decisions that have poor execution and market fit outside of the products that made them big in the first place.

Has anyone actually studied the best way to hire devs? Like a real, independent study that measured and compared results across, perhaps, a wide array of metrics?


> Has anyone actually studied the best way to hire devs? Like a real, independent study that measured and compared results across, perhaps, a wide array of metrics?

I don't know how you would ever strive to do such a thing when people can't even agree how to measure productivity.

> Of course maybe this explains why most of the big tech companies have seemed pretty stagnant for the last decade, largely failing with products and decisions that have poor execution and market fit outside of the products that made them big in the first place.

In most large companies these things have nothing to do with programmers; the decisions are made by management and products are designed by PMs. Hell, you can't even necessarily blame buggy products on programmers: I've been on projects where everyone realizes things suck but if you don't get funding or agreement to work on infrastructure projects what can you do?


> I think they weed out a few, but completely ignore practical development skills, work ethic, soft skills, design and architecture skills, etc.

This is the whole point of the non-coding portion of the interview, and while it’s not possible to get a full picture of this in the short amount of time allotted, it is generally enough to throw out the obvious ones.

> maybe this explains why most of the big tech companies have seemed pretty stagnant for the last decade, largely failing with products and decisions that have poor execution and market fit outside of the products that made them big in the first place

I think this is unrelated to hiring and more a result of corporate policy.


> I think they weed out a few, but completely ignore practical development skills, work ethic, soft skills, design and architecture skills, etc.

Tech interviews are not solely whiteboarding. Even at FAANGs there are system design and hiring manager interviews designed to ask about those sorts of things.


People always say this, but is it true? It’s easy to fire someone. It’s really hard to find someone who can ship (something you won’t get from a whiteboarding challenge).


Engineers who don’t perform well for extended periods of time tend to drain resources from the rest of the team. They require active management; laborious code reviews, they also introduce more bugs and contribute to less robust designs. As for firing, it is a painful process for a manager as it comes with a variety of liabilities and HR involvement.


Seems costly to fire, not just because of HR and management process overhead. People are trying to build successful teams, and regular firings distract from goals, ruin morale, and create an unsafe environment.


Regular firings imply a pretty bad hiring process. There's a spectrum between "regularly fire bad hires" and "regularly reject good hires".

Also, what evidence is there that these high-false-negative practices are actually reducing false positives by a significant degree? In these kind of threads I read the same arguments and assertions, with the same lack of evidence, as I hear from people trying to defend airport security theater. I should start calling these practices "interview theater".


> is it true?

In my experience (hired 10 engineers), yes.

It's technically easy to fire people, but it's emotionally draining on the team and on the manager in particular. Every time you fire someone, the team's morale takes a hit, and if you were firing people often, folks would begin to feel insecure and you'd struggle to keep good engineers.

Smart, good people want to work with other smart, good people. If you're constantly bringing in bad hires (even if you later fire them) then your good engineers will get fed up and leave.

The net value of a bad hire can easily be negative, if you consider the high onboarding costs to get a new engineer ramped up and trained. (Of course, the very best engineers basically sit down and start coding as well as your existing good engineers, but these true outliers are by definition uncommon). Not to mention the cost of the bugs and rework that bad hires produce.

If you use a recruiter, you're typically paying a large fee that you can get refunded after N months (details vary, 3 seems common), so you'd have to be making your assessment in the first N months; that's a lot better than trying to make an opinion on the first day, so if all of the above wasn't true, in the abstract, it would be great to be able to hire aggressively and fire likewise. However, good engineers balk at the concept of a "trial hire"; understandably, as personally I'd refuse to work somewhere that didn't have conviction that they wanted to keep me.

I imagine the relative significance of these points varies between companies and stages; all of these points are from early-stage (<25 person company) startup life; YMMV.

> (something you won’t get from a whiteboarding challenge).

I agree with this point, though I think it's orthogonal to the question of false positive vs. false negative cost optimization.


Sure, but then they shouldn't turn around and constantly keep complaining about a shortage of tech talent.


It's because they are basically just testing IQ. It's not actually programming knowledge they care about. If a person has a CS/EE degree and has been professionally programming for a few years they probably have enough domain knowledge regardless. Then the rest of the interview is testing soft skills.


I think it’s exactly that, willingness to conform, and a very effective filter on age.

I know Google does a lot of metrics on hiring. Have they correlated their practice with IQ anywhere? Guessing nothing public as that would trigger a firestorm.

At the end of the day it’s just the cognitive elite trying to hire the cognitive elite.


They used to interview using the kind of brainteasers found in books like the ones Mensa used to make. The algorithms approach, I suspect, is just a CS proxy for an IQ test just like their old approach was. It would also filter for youth, which they semi-openly advertise as well (see chess literature on brain age for what I mean).

Conformance too (due to the prep time)


This is because it's actually not allowed to use IQ tests as a screening mechanism for most jobs (you need a valid reason and "software engineer" probably isn't good enough to justify the liability). By using algo questions they can select for something that might correlate very well with IQ, that also makes sure the candidate has real coding knowledge, and which has much less liability


Uhhh, no. They are absolutely not testing IQ.

It is instead the opposite. These companies are testing the quality of "who has practiced the most for these types of questions".

It has nothing to do with intelligence. It is instead almost directly correlated with how much time you have spent practicing interview questions.


These company simply want the best of the best. They want people who can whiteboard BFS tree AND also have proven business track records, yada yada. Not just either one of this.


Shame they only test for one of those though. So I doubt they want the best. They want people who can pass arbitrary interviews.


I think companies are trying to find superheros. I would say maybe 5% of the people I've worked with are worlds smarter and more productive than the average programmer (like me).

Those people generally also do well on those whiteboard questions.


Have you considered that there are enough people who can both whiteboard a BFS tree and get stuff done that Google doesn’t need to hire people who can do the latter but not the former?


> I often think what would Google/Facebook would be like if they hired in some experienced engineers that may not be able to whiteboard a BFS tree or can tell you Djikstra's algorithm

I think this happens less than people think. I've been at two big tech companies and interviewed people while at both (and obviously was interviewed myself).

I think what trips people up is that many questions have solutions that are given by "named" CS algorithms like the ones you listed, but also have simpler solutions that are fine too. And honestly, candidates that invoke named algorithms and (maybe eventually regurgitate the textbook algorithm) are often not the good ones (to me at least). Most problems like this often have simplifications that good candidates take advantage of to do something custom (and much simpler) than the "named" algorithms.

Basically, if I'm interviewing you and you regurgitate a famous algorithm... well I'm not going to ding you if you do it correctly, but in my experience, I'm much more likely to give a good review to someone that methodically works out a simple solution instead. Often the people that successfully dig up a named algorithm and apply it can't talk about it very well.

So, I suspect that a lot of the people that complain about not knowing a famous algorithm in an interview simply failed to work out a simpler solution to a simpler problem and didn't realize it.


But you are expected to find the most optimal solution to a problem, and not just a brute force one. And usually an optimal approach would require advanced knowledge of algorithms and data structures.


> But you are expected to find the most optimal solution to a problem, and not just a brute force one.

I'm not talking about brute force solutions. For many problems, there are things in between <famous algorithm> and brute force. Some problems offer simplifications over more general problems where <famous algorithm> is strictly worse than a simpler, more customized solution (same efficiency, but simpler to write and understand).


This is just ridiculous. BFS is such a useful building block. If you're stubborn enough to not spend 10 mins on this the best of luck.


I honestly don't mean this in a snide way.

Can you give a few concrete examples of how a deep understanding of BFS that can't be googled and read in 10 minutes at the time you need it can help you ship profitable software products faster than your competitors?


Do you spend 5-10 minutes googling and reading about the Linear Search algorithm[0] every time you iterate through a list and have a conditional to do something if an element matches some criterion? BFS, or a generic graph search (could be BFS, DFS...), is essentially just linear search except each element can have 0-n direct next elements, instead of 0 or 1. It's not this hard thing that never comes up...

Indirection is great in this trade, a lot of what I "know" is just an index key/search strategy to go look it up again. But a lot of what I "know" I know directly. According to this old paper[1], for many fields including software you need to directly know about 70k±20k random things in the field to be in the running for expert status. Proficiency is also related to how many things you know directly. Thus you can't do an index lookup for everything unless you have no constraints on time and/or don't care about improving your level of expertise.

[0] https://en.wikipedia.org/wiki/Linear_search

[1] https://apps.dtic.mil/dtic/tr/fulltext/u2/a219064.pdf


Can you give a concrete example of when you actually use BFS to solve this?

For me, it always goes like this:

* Am I iterating over a list multiple times?

* Am I iterating over a list and comparing it to some elements in another list?

Turn one of them into a map and continue. It's pretty simple.


I'm not sure I follow your question, what are you referring to with "solve this?"

I usually find DFS/BFS applicable when I'm dealing with data that forms relations like "children" or "neighbors" or "connected". Sometimes that's explicit because the data is already in a tree or graph structure, sometimes it's not. And often rather than looking for a particular element, I want to iterate over all the data connected by the relationship to do something with after as a list/set/map of the data or some of its properties.

A concrete example from a side project (it's more fun than Real Work examples, and people have given other examples in the thread anyway), I was writing a client for the board game Go. If you're not familiar, the data is just a 2D grid (easy to interpret as a graph), black/white stones get placed on coordinates like (3,4) marking intersecting lines. A single stone forms a connected group with another stone if both are the same color and separated horizontally or vertically by one. Groups have a count of "liberties" representing the number of unoccupied points the group can expand to if a stone of its color is played there -- a single stone by itself in the middle of the board will thus have 4 liberties, if you connect a stone then that group now has 6. If you cause an opponent group's liberties to go to 0 by surrounding it, the whole group dies, and its stones are removed from the board with those points becoming unoccupied again. Suicides (causing your own group to hit 0) are ok only if they capture the opponent first, otherwise are invalid moves.

Handling the game rules is easy with DFS/BFS. All you need to start with is a function like get_neighbors(position) which on a grid is trivial, being the 2-4 surrounding points depending on whether position is an edge/corner. Then you can use DFS/BFS (doesn't matter) and several lines of code later you've got a function like get_group_member_positions(start_position) that gives you every member stone's position no matter which one you query first. Now you can make a function count_liberties(group_positions) -- which can be solved as another depth-first traversal problem over the neighbors of each member of the group that are empty and haven't been counted already.

Even less code this time though; have you ever had to write 4 lines of code like "for el in list, for child in el.children(), if child blah, do something"? That's a DFS, just not a general one since you know how many layers there are (or that you care about), and it assumes children aren't shared between els.

From all that you can then have a function like get_stones_captured_by_move(move) that tells you what (if any) stones need to be removed if move were to go through: for each neighbor of the move, if any are the opponent's color, count the liberties for that neighbor's group and if it's 1 then those will die when the move is played (takes the last liberty). If it's all one big enemy group around the move you'll have to account for duplicate positions to remove, but those are minor optimization details. Similarly the fact that everything is recalculated all the time, that could be optimized with more storage.

BFS/DFS are just basic building blocks here.


You won't be able to Google it, because you never ever asked to BFS by name.

You will be asked to find the biggest file in folder structure, find largest modúle in dependency tree or the person in data structure that has no department and thus caused null pointer exception.

You also won't google it, because it is simple and ylnormal programer don't need google for this.


Excellent examples. There is no library for this.


No problem will present in such an easy way as "oh just apply BFS". As part of a big project you often have to use many different algorithms for sub parts, often modify them to suit constraints.

I think the HN crowd is heavily inclined to web apps and also front end. I can't tell you how important fundamental CS knowledge is for backend. I bet you can't use a library or API for how caches work or when paging happens. Knowing these things makes you a well rounded engineer ready to tackle different problems. I can trust you to write a mobile app or work on some part of a self driving car because you have the building blocks to do so. Most of the comments in such threads have no interest in interesting and diverse jobs because "why bother, when will I use this". To any new grad, yes the interviews can be better but please spend time on these things at school. They are an investment in your career's stock.


I mean, I've built and released multiple mobile apps (commercial and enterprise) on both platforms for multiple companies. They've all been mostly successful at doing what the company needed them to do. They look fairly nice as well.

And I don't have this kind of fundamental, "what do you mean 'google it' are you a complete and total fucking moron!?" attitude about anything in software. I routinely browse through google results (mostly SO/Medium) about very basic concepts just to read the words again and re-warm those caches in my brain.


It’s possible to have to solve issues like this even inside of app development. Think back to every time your app has performed poorly: has there been any cases where you didn’t know how to make it faster without giving up in the way you had designed it? Maybe the app was reading from the disk to populate your data model, and that was too slow? Maybe you were performing an O(n) operation for each row in your table view?


I was recently asked to identify pages in our 10 million line application that use a certain piece of business logic. It involved parsing the page and their nested subcontrols into a tree with by doing a modified BFS on the linked files, doing a modifed BFS on the tree to identify the related code behinds, parsing the C# from the codebehinds into a tree, and traversing the C# tree (again with a modified BFS) to find if the code path was hit.

These questions come up all the time. You just need to be proficient enough with algorithms to identify them.


You are essentially looking for patterns in text, your solutions looks not ideal and it takes a lot of time to develop vs just using some linux tools and piping output from one another. 10 millions line is nothing... (commenting based in your gist)

would go even further and say that you could easily have installed something like https://oracle.github.io/opengrok/ in three commands for your organization and extract a lot more value while resolving the issue.


It feels like OpenGrok should be able to do this, but I'm not seeing it. How do you search for a method call in a code path? E.g how do determine i function A calls function C? function file1.A(){file2.B();}, function file2.B(){file3.C();}


Heard back from the OpenGrok developers and they said they don't support the use case I needed. My gist was just a very small part of the overall process (and yes, for that small piece it was trivial to use a linux util instead of csharp).


Right, but you used libraries to do it, right? You didn't actually need to know how BFS works, did you?

10 million lines of code fits in RAM pretty easily. You could use the worst algorithm in the world and still complete that whole task with just a few seconds of compute time.

I think that's the point. You don't really need to know about BFS in most cases, because in most cases you can solve the problem with any old search in just a few seconds.


> Right, but you used libraries to do it, right? You didn't actually need to know how BFS works, did you?

For BFS? Almost never, no. Libraries are generally useful for reference implementations data structures and algorithms that work on collections; I have yet to find an algorithm that works well for graph problems or when you need to subtly tweak the data structure (for example, a binary tree that counts the number of elements on its left and right). The issue with libraries is that they are built for the general use case, and a lot of time in the real world it is non-trivial to transform your problem into the format that the library will expect, so you end up having to do this yourself.


I can tell you really don't know what you're talking about because you can't just "use libraries to do it". You can use a library to parse a given input, but you need to traverse the tree in a specific way. Here, I'll give you an example of the first step of the problem with proprietary info stripped out. https://gist.github.com/tohsa/2d906942f8712abdfc7df72128479c... You plain and simple need to know BFS to do these sorts of things. You're acting like its some act of algorithmic wizardry when its not.

It's not a question of speed. It's the fact that tree traversals are the best way to analyze parsed text. Although, it was quite resource intensive and we ended up distributing the workload among multiple computers so we could scan all pages at once. Luckily this was easy because pure functions are trivially parallelizable.


Ok I see where the problem is. I read through your code and didn't think "BFS", I just thought "knows how to nest for and while loops". I suppose you could consider this "knowing BFS", but I would consider this table stakes. I would never ask about something like this in an interview.

I thought you were talking about actually using BFS on a data structure, in which case I'd use a library to do it so I don't have to reimplement all the loops and because there are modern libraries that would take care of the parallelization (like this one[0])

[0] https://github.com/arjun-menon/Distributed-Graph-Algorithms/...


I agree with you that my gist demonstrates "table stakes", but I think that is the level of tree traversing most interview questions require. I don't think any interviewers are asking people to implement distributed algorithms like the one you linked. They are asking for algorithms that just combine a few of the basics. With that said, I'm inclined to believe our fellow commenters are arguing about the utility of what I shared. For example people siding with me gave examples of finding the biggest file in a file system and constructing a dependency graph to refute the idea that tree traversal are useless and mentioned that there isn't any "deep understanding" in BFS because it's so simple. It reminds me of the tweet by the creator of Homebrew[0] about not being able to reverse a binary tree that so many people bring up when this topic arises. To me that's just table stakes.

On the topic of my example not constituting "knowing BFS", the BFS I shared is just a slight modification of what most students are taught and is close to the second method for level order traversal of a tree on geeks for geeks[1]. If you don't like the BFS usage because it isn't on an explicit tree (although nested HTML templates most definitely form a tree), the result of parsing an AspxFile in my gist returns an explicit tree data structure[2][3] and the helper method[4] at the bottom does a standard preorder traversal[5] on that linked structure. That feels like "actually using DFS on a data structure".

[0] https://twitter.com/mxcl/status/608682016205344768?ref_src=t...

[1] https://www.geeksforgeeks.org/level-order-tree-traversal/

[2] https://gist.github.com/tohsa/2d906942f8712abdfc7df72128479c...

[3] https://github.com/PositiveTechnologies/AspxParser/blob/mast... (AspxParseResult has a reference to the root AspxNode, and btw I didn't write this parsing library)

[4]https://gist.github.com/tohsa/2d906942f8712abdfc7df72128479c...

[5] https://www.geeksforgeeks.org/dfs-traversal-of-a-tree-using-...


I can tell you really don't know what you're talking about because you are mouthing off about jedberg not knowing what he's talking about.


There is no "deep understanding" of BFS. All it is is look at your siblings before your children.

I wouldn't hire an electrical engineer who complained that he shouldn't have to know Ohm's Law, either.


> All it is is look at your siblings before your children.

...And how you are keeping track of that and other such minutiae. What data structures are you using and why? And how about if X which would invalidate your approach.

Also, it's not about "knowing" it. It's about implementing it in such a way as to please the interviewers.

It's pop quiz nonsense.


Programming is exactly about handling such "minutia". It's a totally fair question.

As for pleasing the interviewers, of course it is about pleasing the interviewers. They're making the "buy" decision on the talents you're "selling". Of course the seller needs to please the buyer to close the sale. I don't know how it could work any other way.


> And how you are keeping track of that and other such minutiae. What data structures are you using and why?

This is a good question, IMO, because it tests “I need to do this, which data structure would work well for it”, which does come up often in real life.


No but I can give a few examples where I refactored code from these antique pointer-based trees (inspired by classic CS books, half century old now) towards something more cache friendly, and improved performance by an order of magnitude.


BFS is common sense. It’s what you use when you’ve lost your car keys for example. Quickly check each room in the house, then if no luck go one layer deeper in each room.


uh, I thoroughly search each room, starting at the left corner and recursively iterating via a hilbert curve.

doesn't everybody?


Two different approaches. Each have their adherents. But when someone can’t find their phone or keys that that just had, they probably don’t start by ripping one room apart top to bottom.


I might pull the couch cushions, but I'm not going to start moving furniture until I check other places first.


so, basically A* search


I would certainly probe deeper if given that as evidence for a strong grasp on the utility of BFS.


So you’d do a DFS on a BFS


That's definitely now how I do it. I go deeper into each room, the depth (as well as the order) being decided by (roughly) how much time I spend in each room every day. E.g., Go waay deeper in living room, less so in bedroom, lesser still in bath room and so on :-). This I'd imagine is "more" common sense than than an un-informed BFS?


If you just go depth, it is well depth first :)


I actually thought this through a bit :-) Neither is it a DFS, unlike in DFS I'm expanding nodes at different depths. E.g., I'm shallow expanding bathroom/kitchen compared to living room. Only when I've exhausted living do I return to kitchen again to do a deeper search. I wonder if this kind of search has any other use. Debugging seems like a similar activity. Go deeper into logs, if nothing turns up then examine metrics, read code, return to logs again etc.,?

Sorry, past midnight here after a busy day at work :-P


Heuristically guided search. :) For some nodes you go wide, for some deep, sometimes you retreat back up a few levels instead of exhausting a subtree (but you might come back to that subtree later), all depending on what the heuristic says is more likely to get you to your goal the quickest. A* is a well-known base algorithm for this, widely used in game programming to efficiently find the shortest path from A to B in the presence of obstacles etc.


A DFS would be you check your living room, you check under the cushions of the sofa, you tear open the cushions and comb through the insides... all before glancing at your bedroom when you didn't quickly see the keys in the living room.


This is actually not how I search. After the first search, if I am getting frustrated, I do what I was told when I was a child: "start picking up stuff until you find it". So I guess that's kind of a depth first search after going over the top layer.


I'd use an indexed search and remote activate the beeper in the key chain


I don't think I've ever lost my car keys so does that make me a NULL pointer!


In that case you get O(1) regardless of algo choice.


> If you're stubborn enough to not spend 10 mins on this the best of luck

I know. These people are expecting to be paid way above the average salary - I'd expect them to know the fundamentals, or (more importantly) be able to figure it out.

"BFS?? I'd use a library for that" - well, thanks for that... instead of hiring you I'll just download some libraries instead.


Watch me get downvoted to hell though :)


The creator of ruby on rails wouldn't pass a whiteboard interview. Ruby on Rails had more of an impact at Twitter, Github, Airbnb than BFS is my guess

DHH's tweet https://twitter.com/dhh/status/1085987159406927872


There's a reason such tweets resonate so well:

1. Creator of top software project can't pass whiteboard interviews.

2. I can't pass whiteboard interviews.

Therefore, they are stupid for not hiring me.

It strokes everyone's inner narcissist--why spend the hours on leetcode, they are stupid anyway.


i mean if had to choose between no graph theory vs no ruby on rails...i would probably go with no ruby on rails


What if you had to choose between someone with a proven track record of building high quality software used by millions of people who has also shown they're capable of leading groups of people in successful projects but hasn't memorized the specific algorithm you asked about and another candidate who doesn't have as good of a track record but can totally nail that easy algorithm you asked for?

Edit: Typos.


You think every candidate who comes in is like this. There are anomalies and outliers. The truth is resume padding is so common in the valley. Everyone can just say all these things. It's very hard to hire like this.


I don't work in SV. I assume it's like everywhere else where a potential employee who feels their skills are weak will take credit for things done by their teammates even if they were only tangentially involved.

My above comment was strictly related to the idea that DHH shouldn't be considered for a job over anther candidate who is an unknown quantity simply because DHH apparently is not good at algorithm problems in interviews.


Would you choose one-hit-wonder over proven engineers (Jeff Dean, Sanjay, other ex SUN microsystems folks?) that lead high-profile projects?

I know that sounds rude... but one seems better to be a leader while others are better engineers would you agree?


Total cop out answer but if DHH and people like Jeff Dean are both interviewing for a position with me you can be sure I'm doing everything I can to hire all of them. Even if it means starting entirely new departments.

I'd totally fanboy and hire Jeff though if it came down to just one though.


I don't mean to diminish/belittle DHH. What he's done (web framework, productivity SaaS, self-help books, sales/marketing, conference speakers, racing) it's not what Google does (web-browser, OS, AI, maps, search, scale, etc).

I also don't get why people like DHH is assumed to be a "miss" for not being hired by some of these company...

DHH is a unique individual with his own way of thinking. He wouldn't be DHH if he works for someone else (or under someone).


You don't generally hire people like that to work for you on something specific. You hire them with a very broad goal and give them the resources to accomplish the task how they see fit. With a bit of nudging here and there you should end up with a very marketable outcome wether it's a product or a prestigious research division or widely used piece of software that everyone knows is associated with your company.

What DHH does could absolutely be incorporated by Google. Angular => RoR, GCE => Saas, conference speakers => conference speakers.

Anyway the point is that even at a company like Google there's plenty of room for people that haven't memorized algorithms and data structures but companies that only interview on these sorts of things are missing out on them because they seemingly don't care or haven't figured out how to interview someone substantially different from what they normally hire.


SaaS != GCE.

I find the skillset required to build Basecamp differs greatly with building AWS/GCE portfolio (with over hundred different services that can be combined to deliver solutions for multiple ranges of companies...)

I don't think Google was looking for someone to build RoR or Angular. Those were merely side projects that came out once every few years. No offense but some of the key components of RoR were implementation of Martin Fowler's Enterprise Application Architecture patterns.


I wouldn't hire someone who cares so little about getting a job that he didn't spend the most basic amount of time studying for obvious questions that he was of course expected to be asked.

Such a situation would show me that he either does not care about getting the job, or is so arogent that he automatically expected that people who throw job offers at him.

That shows that this person has horrible personality problems and that I would not want to work with him, no matter how much he has accomplished in his life.


I didn't know about "BFS trees", do you have any references? I tried Googling but I could only find breadth-first searching (which I do know well, though apparently not the acronym BFS), but that's just a traversal algorithm.


BFS is "Breadth first search". One tree you would do this on is a BST or "Binary Search Tree". Probably OP got the acronyms mixed up.


There's actually a thing called BFS tree. It's a tree that depicts the order of node expansion/visitation when a graph is traversed BFS. Even I wasn't aware of it until I recently read Peter Norvig's AI book. However, I'm not sure if the author referring this.


Right, since I didn't pick up on the acronym I thought I had missed something. Cheers!


Experienced engineers can BFS the tree. They may not remember djikstra.


These interviews do filter out any engineers that can't solve these algorithm problems on a whiteboard, but they don't necessarily filter out people who have a proven business track record and can get projects done on time and under budget.

I think the phrase "jack of all trades, master of none" is overused and doesn't hold a lot of truth. It's very possible to have a lot of experience and skill in many different areas. Maybe there's even a positive correlation between being a very good programmer that can pass whiteboard interviews, and being a pragmatic, get-it-done type of engineer.


Yeah honestly, I think those are the type of engineers that are more suitable for managing other engineers, and the really heavy ones are more suited for strictly engineering.


I cannot help but think that these big tech companies (FAANG, et. al) are missing out on diversifying and increasing their engineering expertise by passing over developers like you.

There is still so much stupid money out there that it doesn't pay to do this. Literally immaterial, and it's more cost-effective to hire for a narrow-but-consistent set of requirements.


Programmer distillation. Companies need to admit that only trying to hire a single type of person is not going to work. It's just like with petroleum: there's nothing wrong with the other products you get from the mix. You just have to appreciate what there is and make the most of it.

I bet you're quite good at something (perhaps multiple things), but they don't value it. Their loss. I'm glad you found something that works for you.


> Companies need to admit that only trying to hire a single type of person is not going to work.

Why? It's not so clear to me that it's not working right now. These companies seem to be doing completely fine.

If hiring programmers who aren't good at programming puzzles is a competitive edge, I would expect to see other companies hiring these programmers and succeeding.

It seems more likely to me that there is (at most) a very marginal loss from hiring this way. It's not the fairest way to hire, it's not the most equitable way to hire but the evidence doesn't suggest to me that it's not working for these companies.


"If hiring programmers who aren't good at programming puzzles is a competitive edge, I would expect to see other companies hiring these programmers and succeeding."

You're begging the question. Other companies do hire people who are excluded by a certain class of employer, and that's exactly why some get outraged by the types of quizzes that are used. The difference between the standards creates cognitive dissonance over one's ability and status. It's effectively a caste system, and it involves persistent blind spots about discrimination, whether towards protected classes or not.

I can't pass an Amazon or Google phone screen - both of them invited me to try, and they then made me feel very out of place. I'm not a software engineer per se and I didn't get my CS degree from a top school. Yet I have worked for a company that Google outsources important work to, proving I can do useful things that Google needs done and maybe isn't even able to do in house.

I don't go around raging against Google hiring who they want, partly because I'm probably better off not working there anyway. But I understand where people are coming from when they do get angry, even if it is the sign of an imperfect character.

From an employers point of view, they just want to grab the employees that are suitable for their goals and jettison the others. But from a potential employee's perspective, it seems like if I'm not good for one job at a company, I should be good for another. Rejection seems unreasonably total. If, by analogy, you deal in second hand cars, it's a reasonable business model to buy virtually any car so long as the price is right and you know who to sell it to. But not all businesses are run like that of course. It aggravates people that there is a narrow vision for who is useful.


> If, by analogy, you deal in second hand cars, it's a reasonable business model to buy virtually any car so long as the price is right and you know who to sell it to.a

Very good analogy. And true. My dad used to own a used car dealership back in the day. He bought pretty much anything he could get for a good price that was in decent shape. If he only bought cars that were in perfect shape, he'd have pretty much no cars on his lot.

And I've worked for companies whose bosses are so damn picky about who they hire that they would go without hiring a single person even after conducting hundreds of interviews themselves over six months, as the rest of us were struggling to keep up with the workload.

It got so bad one time the higher ups eventually had a recruiter just pick a few people and said "Here, these are your new employees. Get them up to speed." and he just had to accept it.


Been there. At my actual job (a small IT firm in Europe), my boss spent almost half a year searching for somebody to hire. All the times it was like "they are too old", or "don't know enough", or just for a different POV.

In the meantime, collegues are leaving the gig, making my level of stress go up.


It's really hard to argue with money printing machines that anything they're doing now is wrong. I don't even want to bother much myself if I can help it... Sure, maybe if they changed some things they could print money a tiny bit faster, or set themselves up to survive the next phase of the economy in some years when it's no longer so easy to print money (lots of companies die over ~15 years, which also corresponds to the global economy's doubling rate...). But also any change has an element of risk, so the money printing could slow down or put it in a worse long-term position. When something is working great right now, you're reasonably going to be more risk-adverse about changing things.

We do see other companies hiring differently, and being rewarded in the market, in part, for it. Most of the time it's a marginal reward. Sometimes though we get a new FAANG, staffed by people who wouldn't have made it through FAANG's ringers.


What we're probably seeing is that the FAANG's have acquired so much fame and wealth that they can afford an enormous false negative rate in hiring that would sink a smaller company.

Its the difference between fracking the shale for every precious drop because that's all you've got where you are vs. being able to just sink a short pipe in the ground and stick the sweet crude that gushes out into barrels.


> Companies need to admit that only trying to hire a single type of person is not going to work.

Um.. have you looked at their stock? Investors would probly want them to continue coding puzzles if they knew about that.


>Programmer distillation.

That's a great way of putting it. Hard to see any other explanation.


How many people have gone through the full regiment of training for interviews described by the original linked author and failed at every major tech company?


> my brain needs more time than the average programmer

Well, maybe not even the "average" programmer, but just the elite of the elite Google-tier programmers ; ) I feel the same way. When I was young, I thought that absolute mastery was within my grasp but after 25 years, tons of self-study, a couple of college degrees and yet still a lot of surprising rejections, I have to concede that while I may actually be very good at what I do (I'm among the most respected and most sought after everywhere I've ever worked), there are still people out there WAY better than I am, and that's OK.


If you want my opinion, these companies aren't looking for awesome talent. They're looking for people who will put up with their schedules, demands, management. They don't want creative thinkers with experience in multiple fields. They're looking for one-trick ponies that will do what their told and will be happy to get stabled by 40.

You're better off following your own path and making your own things happen.


"They don't want creative thinkers with experience in multiple fields"

You have no idea how diverse people are in terms of talent at big companies. This is a myth peddled here at HN that FAANG employees write CRUD apps and are one dimensional. The best perk of my job is the random lunch scheduler where I've met a former Olympian, someone who is on the Rust core API team and a professional ballerina + software person.


I work at Google some of my co-workers work reasonable hours, quite a few have been there for 10 years.

The same was the case when I worked at Mozilla..

But I've always felt the interview process at these places extremely arbitrary.


> Finally, I realized my brain needs more time than the average programmer to find patterns in this type of problems.

I'm the same way. I'm really good a identifying solutions to a problem. I'm really good at identifying the costs/benefits/issues with each of the problems. However, I take a while to get there. I may figure out one (suboptimal) solution quickly, but it takes me a while to pick out a variety of them and identify the one I think is the right one for the current situation.


Story of my life, watching everyone else quickly come up with the wrong answers. :P

In school would usually (ok, often) get highest score, but took the longest to finish.


yea, speed is very overrated in a lot of cases. Too bad big companies don’t understand this or refuse to admit it.


> Finally, I realized my brain needs more time than the average programmer to find patterns in this type of problems. > I gave up on my goal to land a job in one of these big corporations.

Maybe we are just not good enough.. And maybe it's sour grapes for having been rejected by them, but honestly I don't feel I would be a good fit for Google or FB ideologically. I value user privacy and freedom too much. In my eyes they are both evil-corps.


It's contextual. I've worked at a big, cool company before, and the things I had to be good at to survive (mostly non-technical) simply were not important to me, nor very useful outside of work. They were core requirements for long-term success there, though.


I'm interested in hearing more about that. What were the non-technical requirements that you didn't like?


Mostly the highly-significant role that social relations play, far beyond what I have experienced at <100ppl companies. This was also in vidya, so it was extra...I don't know if I'd say "vicious," but competitive for sure.


What's vidya?


I am just leaving a comment to commiserate with you. This is exactly how I felt. And I have a similar story. It was a depressing time.

> Finally, I realized my brain needs more time than the average programmer

I also came to this conclusion. I accept it and focus on my strengths as a team lead instead.


I was a programmer for 10+ years and I couldn't pass the technical interviews for these companies either. I started down the path of trying to self-learn Computer Science but reading books wasn't enough for me so I wen't back to school for it. Around the end of my CS bachelors I pivoted to hardware and stuck around for a masters in ECE. Now I work at one of the companies mentioned. It is much harder to learn CS on your own than it is in a structured environment.

Your experience allowed you to move toward doing work that excites you. Even though you didn't meet your goal, you still had great success.


I call this "slow coding". Taking time to understand a problem, try out solutions, take a walk, come back to it, no pressure, no marathons.

Just progress an inch at a time.


2.5 years out of college sounds like it's still in that sweet spot where you can just grind Leetcode and pass interviews.


The truth is that it is a tough problem. Everyone wants to figure out if you're smart and can figure problems out. I have, however, seen 10 year engineers have trouble reading a small data structure and writing 2 nested loops. So I think the biggest issue is just nervousness.

I mean yes, some engineers are going to be better at interviews than others but we gotta go by some signals. We had to flunk a few because it was "we see the depth of knowledge the person describes, but we have to go by the signals we saw, otherwise we're just randomly picking people".

Point is it is tough. However it does say something that our interviews are just a bunch of quizzes and studying for a month will make a huge difference. When hiring the goal is to find out if the person is good, not if they crammed, but cramming does work quite well.


Don't you think you're taking a bit of a fatalistic approach to things? I applaud the linked article's can-do attitude and pro-active approach to studying for what to be honest is a slightly silly interview process.

I'm not arguing that it shouldn't be the way it is, and I'm also not arguing against.

Claiming "Finally, I realized my brain needs more time than the average programmer to find patterns in this type of problems." feels a little bit like you've given up and that in itself strikes me as the worst sign.


have you tried lately? it seems like it’s gotten a lot easier lately since the market has been heating up. Source: tried a few months ago and got all the offers also


Congratulations on getting the offers.

I haven’t applied lately. Working in one of these big companies was a dream of my younger self. Nowadays, I prefer companies where I can work at my own pace. Moreover, while the salaries at these companies are exaggeratedly high, especially in San Francisco, I feel that my current compensation package is good enough to live a kind and peaceful life.


I don't get some peoples fascination with working for FAANG anyway. As you said yourself, you've had some amazing jobs outside of FAANG. People seem to hold such prestige for working at a household named software house but that doesn't mean the work is going to be any more interesting than at any of the countless other technology companies out there that are on the bleeding edge.


It’s the same reason high school students apply to Stanford and MIT; there are amazing programs everywhere but top-level universities carry prestige and may have higher quality opportunities.


I did cover those points. As I said, the prestige is misguided (in the case of FAANG) and you don't need to go down the FAANG route to have access to higher quality opportunities.

Those companies sure want you to believe what you're claiming because it means they get the first bite of the cherry but the reality is very different (from my experience anyway).


> The prestige is misguided (in the case of FAANG)

I strongly disagree, and I'm not sure why you would say that. I've heard that working at Google is a golden stamp on your resume, and you will be able to easily get a job at any other company. You'll probably even be able to skip the coding challenges in any future interviews.


> You'll probably even be able to skip the coding challenges in any future interviews.

Is this speculative or does this actually happen?

As a team leader I'm involved in hiring and I certainly wouldn't treat one applicant any different from another regardless of their previous postings nor experience (except when I'm headhunting someone I've previously worked with). My own experience interviewing has taught me it's easy for people to put stuff down on CVs (eg they might have legitimately worked at Google but through an acquisition rather than hired by; or not even with the team they suggest they have). So I would consider short-cutting part of the interview process in the way you described to be grossly negligent.

I don't dispute that your CV is more likely to get short listed however you can certainly still sell yourself without having FAANG on there.

My general point is that while I don't disagree that having FAANG on your CV will undoubtedly look good, however a good engineer shouldn't have any problems getting awesome jobs with or without FAANG. Thus is the prestige attached to FAANG really equatable in the real world or is it perhaps disproportionately hyped?

Maybe this is just one of those differences between how people are hired in SV (where I haven't worked) and London (where I do work)?


Purely speculative, but I would hope that it is true. I think it would also depend on your role at Google.

I think it would be pretty rude and unnecessary if you asked a high-level Google employee to do a whiteboard algorithm puzzle, or a take-home assignment where they have to build a little todo list app. Especially if they are a Distinguished Engineer or a Google Fellow. I don't know where the cutoff is exactly, but at a certain point no-one should ask you to do any more coding puzzles. You'll still go through interviews, but they shouldn't need to test your basic programming skills.


I agree if you're hiring someone with a notable reputation then you wouldn't run them through the same kind of coding challenges but I'd expect that would be the case regardless of whether they had worked at FAANG, open source, start ups or wherever else. Thus we come back to my point that a decent engineer shouldn't have any problems getting hired regardless of having FAANG on their CV. What I was wondering was whether having FAANG (rather than reputation) allowed an applicant to shortcut parts of the interview process.

To be honest, judging from your last post I suspect our opinions aren't that far apart. :)


outside of Silicon valley... maybe.

In Silicon Valley, everyone knows that it is fake prestige and the fact that you worked for a FAANG doesn't really mean anything. I both know excellent and mediocre candidates coming out of FAANGs. It literally carry no information besides the fact that you are probably more attracted to prestige.


Oh, that's interesting! I think "fake prestige" might be a bit harsh, and I'm sure that doesn't apply to the very senior engineers who earn > $500k per year.

A few years ago I was contacted by a Google recruiter, but I realized that it was going to be a very junior SRE role, so I wasn't interested in that. I could have put Google on my resume, but that probably wouldn't have been very impressive.


I mean, money is money.

It still makes sense to work at one of these places that pay twice as much as everyone else.


Do they though? I think that they majority of people at FAANGs are actually taking a salary cut compared to what they could get somewhere else. (anecdotal data from all my friends interviewing).

It is simple offer and demand. The supposed prestige of FAANGs also mean that more people wants to get in and unless they really want you, they would be stupid to overpay you.


You can have higher quality opportunities everywhere; it’s just that it’s often easier at those companies. Just like going to certain universities means it’s easier to find professors who lead their field, recruiters from better companies, and more access to be with smart people.


But is it actually any easier given you have to also factor in going through their painful recruitment process and actually getting employed by them in the first place?

Maybe my things are different in London than they are in SV but I've never had any issues. Quite the opposite in fact; I've been turning awesome jobs down.


Don't forget a lot of it comes down to compensation as well. It's not unusual for FAANG company to pay 2x more compared to another public company for example.


That really depends on your basis for comparison because there will be a lot of variation between wages for different jobs within the same company; let alone different jobs in competing companies. It can even vary depending on how good your recruiter is, how generous the management for the vacant position are, the type of job that's on off and how important that position is to that company (are they desperate? Is it an area of strategic growth? etc).

Anecdotally I've really not seen the 2x trend you described and I have spent a fair amount of time negotiating peoples wages. Plus engineers who are really concerned about maximizing their income will generally turn to contracting rather than permanent work anyway (at least that is the case in London where contracting is common place).

Suffice to say, I'm pretty unconvinced that FAANG pay people twice what any other business would. Maybe if you're looking for jobs outside of tech hubs (like smaller towns away from expensive cities) but other tech firms in London (and SV I'd guess?) would have to pay competitive wages else risk not attracting any talent.


I've seen total compensation packages of $100k for senior engineers in SF/SV before (really low side), FAANG comparatively would pay $350k+. There are plenty of public companies in SF/SV that pay senior engineers $175k total compensation.

I also want to clarify that I didn't mean they always pay 2x over the competition, I meant that it's not unusual for them to. Also when I say FAANG - I kind of included similar large companies (Microsoft, LinkedIn, Salesforce, etc). There's also a lot of large companies that come close, maybe 80-90% of FAANG pay.

>Plus engineers who are really concerned about maximizing their income will generally turn to contracting rather than permanent work anyway

I think it's pretty difficult to get steady contract work that pays more than what FAANG does. I charged $175/hr when I used to contract and it was decently steady, but that only comes out to around the same I would be making at a FAANG minus all the perks/benefits. Also when you get to higher seniority levels, your pay at FAANGs start to reach into the 6 or 700's, meaning you'd need a contract rate of $300+/hr to compete.

Usually when companies need that high level of technical architecture/leadership - they'd normally hire someone full-time rather than use a contractor, so it would probably be difficult charging that rate while getting steady work.


> Also when I say FAANG - I kind of included similar large companies (Microsoft, LinkedIn, Salesforce, etc).

Ahhh I was including those sort of companies (baring Microsoft) as part of my counterexample. If the discussion was "any large / reputable organisation" then my comments would have differed a little.

In any case it sounds like London is very different to SV. It's very common for senior engineers to contracting and that's precisely because the difference in pay between permanent and contracting is night and day (the polar opposite to what you were describing in SV)


> FAANG - I kind of included similar large companies (Microsoft, LinkedIn, Salesforce, etc)

FAMLANGS


I bet a contributing factor in this is that you think other people are "faster". They're not, we're not. The only difference between you and someone who's good at these interviews is that the good ones accept that uncertainty and are willing to work through it and you aren't.

Nobody aces those interviews in the way you probably think; by just magically knowing every detail.


How did you enter the game industry?


I joined a game studio as a Generalist Programmer, I started writing infrastructure tools and doing things that nowadays people refer to as “Development Operations (aka. DevOps)”. Then, I continued collaborating to game-specific projects, improving bits and pieces here and there. Thanks to my background in C++ I was able to make significant contributions. I also have built a few mobile games for my children to play with, but I’m not a game designer and don’t have artistic skills, so I try to stick to the algorithmic part of the projects.


How did you find the jobs through those books and competitive programming exercises?

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