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Re:Jane Street – Our software engineering interviews are cha... by janalsncm on Thursday November 12, 2026 @07:21PM (#50476422)
Leetcode was stupid before LLMs and now it’s even less useful as a signal.

What I want to know is whether someone has basic DSA understanding. Is the person familiar with any programming language. Can they translate business requirements into code? Can they disambiguate weird things PMs say into a viable plan?

You do not get a better signal about that from asking harder leetcode problems.

Never once in my career has writing a tricky algorithm under time pressure been relevant. The closest thing I can think of is debugging complex systems in an outage, but then it’s more like familiarity with bash commands and general debug skills.

As for LLMs and coding, companies need to figure out how to differentiate good and bad outputs here and what lasting engineer inputs to select for. And I don’t have any idea about this.

Re:Jane Street – Our software engineering interviews are cha... by threethirtytwo on Thursday November 12, 2026 @09:11PM (#50477192)
You missed the point. I’m not saying I support dsa but you are arguing against the weakest version of the reasoning behind why companies use dsa. It’s used as an iq test. IQ is highly correlated with many things associated with intelligence yet even though we don’t take iq tests on a daily basis it still correlates.

The argument was dsa functions like an iq test. It’s not relevant to the job (in fact it’s harder than the job, far harder) such that if you do well on it companies can be confident you can do well.

Re:Jane Street – Our software engineering interviews are cha... by noduerme on Thursday November 12, 2026 @09:54PM (#50477528)
Is DSA knowledge really pointless or just a stand-in for an IQ test?

I've been engineering systems for 25 years. On a macro level, most of my time is spent considering the right tooling and stack for a job, balancing budget and time constraints and efficiency against how things may need to scale in the future. On a micro level, in the data model and in the code itself, choosing the best structures for a task is important for maintainability and overall coherence.

In my experience with LLMs, I often need to guide them toward choosing the right ways to model data on the code and database level. LLMs seem to prefer json blobs of unstructured data, naming conventions that drift over time, argument structure patterns that change from one piece of code to another. The net result is a lot of tables and code that an LLM needs to read back through, find all the linkages, and recommit to its window before any debugging can take place. It makes human debugging very difficult if, for example, an LLM decides to just store all the userdata in some json column and then decides to add some kind of stateful preferences to that, and other state to something in memory, and then parse the memory falling back to the database state. I've seen a ton of things like this where weird ways of handling state kinda work, until they don't, and it's extremely difficult to figure out what is taking precedence when or where a thread race is coming from.

All this is to say that DSA knowledge may be even more important when LLMs are writing most of the code, because an unguided LLM will write stuff that can practically only be maintained by an LLM, and make design decisions that don't cohere or scale. If that's not really a problem, and you're certain that the code you're investing in writing will never need human intervention, then I guess it doesn't matter. But with a large enough system designed that way, the boundaries and edges of poor DSA choices aren't going to be apparent until either something breaks or you need to grow.

Re:Jane Street – Our software engineering interviews are cha... by cweld510 on Thursday November 12, 2026 @10:13PM (#50477707)
DSA is plenty relevant to the job. There’s lots of professional programming that’s heavy on DSA.
Re:Jane Street – Our software engineering interviews are cha... by threethirtytwo on Thursday November 12, 2026 @10:43PM (#50477965)
It’s very rare. And often people end up using libraries. All pointless now with LLMs
Re:Jane Street – Our software engineering interviews are cha... by ralfd on Friday November 13, 2026 @04:48PM (#50490346)
Plus: IQ tests are illegal for hiring, but leetcode questions are not. That is why it is used as a substitute for an iq test
Re:Jane Street – Our software engineering interviews are cha... by tptacek on Friday November 13, 2026 @05:58PM (#50491346)
IQ tests are not illegal for hiring. They're presumptively legal for virtually all white-collar hiring.
Re:Jane Street – Our software engineering interviews are cha... by 9rx on Friday November 13, 2026 @09:59PM (#50493305)
There is no written law prohibiting IQ tests, but they are assumed to be legally indefensible and the colloquial term for legally indefensible is, you guessed it: "illegal".
Re:Jane Street – Our software engineering interviews are cha... by tptacek on Friday November 13, 2026 @10:30PM (#50493526)
No, it's not. Huge companies that are enormous targets for employment attorneys routinely do IQ testing. The companies that deliver and proctor general cognitive tests for employment have logo crawls, like any other SAAS company. This is just a big Internet myth.

The reason more companies don't IQ test is that it's an ineffective tool for candidate screening. We all intuitively get that as software developers: imagine hiring off an IQ test rather than just having someone write code.

Re:Jane Street – Our software engineering interviews are cha... by 9rx on Friday November 13, 2026 @10:43PM (#50493613)
It's not what? Your train of thought seems to have gotten cut off. The huge company story is fun too, but it also seems to have gotten cut off not going anywhere. You're right that the "internet myth" considers it to be legally indefensible, and thus, colloquially, illegal. But we already covered that earlier, so whatever it was you were trying to add on top of that also appears to have gotten cut off as well. Was this message delivered via Outlook?

Regardless, you vastly overestimate how much effort is put into hiring. The vast majority of companies would never study the effectiveness of IQ tests to know if they are useful or not. If they had a gut feeling that an IQ test would be helpful they would try it on that basis, except they wouldn't try it because they've read online that IQ test use is illegal; meaning that it is considered to be legally indefensible.

Re:Jane Street – Our software engineering interviews are cha... by tptacek on Saturday November 14, 2026 @12:10AM (#50494184)
It's not legally indefensible. It's not illegal in any sense. It's not proscribed. It's presumptively fine in white-collar employment. Large companies screen candidates with general cognitive tests. Well-established companies administer those tests and brag about their large clients. None of this is a secret.

So it's difficult to see how to square what was previously said on this thread, about IQ testing in employment being "illegal" or "legally indefensible". Those are trivially falsifiable claims. Every HR department in the world knows that.

Re:Jane Street – Our software engineering interviews are cha... by 9rx on Saturday November 14, 2026 @10:17AM (#50497708)
It would appear my message was also arrived malformed. What a terrible week for tech!

What I said, quoting from earlier, was "considered to be legally indefensible". Whether or not it is legally defensible is for the courts to decide, but it is clear that it is considered to be. Unfortunately your full comment didn't arrive, but what we did get was "This is just a big Internet myth" which appears to have you echoing that it is considered to be legally indefensible. You cannot have a "myth" without belief.

Where the law is abundantly clear (YMMV, law is jurisdictional) is that hiring criterion must be related to the job. It asserts that selection tests must be reasonable, bona fide, and tailored to actual job duties. That does not strictly prohibit IQ tests, but there are effectively zero jobs where an IQ test would be seen as reasonable, bona fide, and tailored to the actual job. Whatever exception you can find is just that: an exception.

Re:Jane Street – Our software engineering interviews are cha... by tptacek on Saturday November 14, 2026 @11:03AM (#50498098)
It doesn't prohibit IQ testing at all and your argument fails empirically because large companies do in fact broadly employ IQ testing. None of the rest of your comment makes sense in light of that fact.
Re:Jane Street – Our software engineering interviews are cha... by 9rx on Saturday November 14, 2026 @11:30AM (#50498315)
It looks like your message got cut off again. Allstate is well known for not using IQ tests, rather their proprietary JEPS assessment, so be aware that whatever followed to connect IQ tests and Allstate is missing.

Moreover, on JEPS, Allstate does not use JEPS in my jurisdiction. There is no public knowledge as to why, but legal compliance would be a reasonable explanation. Use of JEPS may even be illegal.

Perhaps you had a different company in mind?

Re:Jane Street – Our software engineering interviews are cha... by tptacek on Saturday November 14, 2026 @11:33AM (#50498341)
The opposite thing is true of Allstate; they're a banner Wonderlic client. You can't just bluff your way through this.
Re:Jane Street – Our software engineering interviews are cha... by 9rx on Saturday November 14, 2026 @01:31PM (#50499484)
It is true that Allstate is a Wonderlic client, but Wonderlic does not use IQ tests, so the connection is not clear. Did your message get truncated again?

Could it be that you are using "IQ test" as some catchall term for any type of cognitive test? You could define it that way in a vacuum, but that is not how it is being used here. The initial comment was clear about how it was being used. In context, "IQ test" was being used to refer to IQ tests that are academically recognized as IQ tests (WAIS, Stanford–Binet, etc.). HR department pet assessments do not fall under that.

Re:Jane Street – Our software engineering interviews are cha... by janalsncm on Friday November 13, 2026 @05:55PM (#50491309)
The problem is that because people believe that Leetcode is a good test of job performance, it implies that the best leetcoders will be the best software engineers.

So to the extent that we software engineers were complicit in that myth, we can’t blame management for believing that AI can replace human software engineers now that AI is the best leetcoder.

Re:Jane Street – Our software engineering interviews are cha... by WalterBright on Thursday November 12, 2026 @09:26PM (#50477315)
To get into Marine boot camp, there's a minimum strength test.

To get into college, there's the SAT test with a minimum score.

To get a high paying software job, there's the leetcode test.

These are gates meant to filter out the obviously unqualified candidates. Unqualified candidates waste the time of the candidate and the company. The real interview comes after that.

Re:Jane Street – Our software engineering interviews are cha... by batshit_beaver on Thursday November 12, 2026 @11:40PM (#50478429)
All of these filter for the amount of time the person spent _preparing for the test _.

And leetcode is not something you prep for once in your life, but every time you switch jobs.

Re:Jane Street – Our software engineering interviews are cha... by WalterBright on Friday November 13, 2026 @12:07AM (#50478603)
A friend of mine wanted a job at a FAANG company. He knew there'd be first a leetcode interview, and complained that he'd have to spend 3 weeks studying for it. I said those three weeks would be the best investment he'd ever make.

So he did the three weeks, passed the leetcode, passed the interviews, and now makes 400k.

When I was 10 or 11, I asked my dad what MIT was looking for in a student application. He (an MIT alum) told me. I picked out the things I could do (being captain of the football team was never going to work for me), applied to MIT, and got rejected. But Caltech, Dartmouth and Johns Hopkins did admit me.

You do what you gotta do.

Re:Jane Street – Our software engineering interviews are cha... by gopher_space on Friday November 13, 2026 @04:20PM (#50489872)
I'll never understand why proponents of the "grindset" mentality get into automation. If you want to grind for that kind of money just go into sales, it's way easier and they give you an office with a door.
Re:Jane Street – Our software engineering interviews are cha... by WalterBright on Friday November 13, 2026 @04:31PM (#50490080)
I'm a terrible salesman, and besides, I just don't like doing it.
Re:Jane Street – Our software engineering interviews are cha... by keeda on Friday November 13, 2026 @12:20AM (#50478685)
I wholeheartedly agree with this, and I always thought leetcode questions and tech interviewing in general was broken, but as a filter for unqualified candidates, they were pretty effective. Which really matters when you have hundreds of candidates to sift through.

The biggest problem, of course, is that they also filtered qualified candidates (I personally got filtered out multiple times and I'd like to believe I was qualified!) But it is an understandable compromise whenever there is an extreme asymmetry in the volume of candidates and volume of interviewers, and the fix for that is simple: you study for the test (as you pointed out.)

Note also that as grandparent comment indicates, this test is a necessary but not sufficient condition; it's just to get your foot in the door for a deeper evaluation.

Re:Jane Street – Our software engineering interviews are cha... by marcus_holmes on Friday November 13, 2026 @03:57AM (#50480378)
I think the complaint is that the test has nothing to do with the job.

It's like "to get into Marine boot camp, there's a minimum crochet requirement".

Solving leetcode problems has nothing to do with commercial coding. It's an unrelated hoop that we make folks jump through, because it's easy to measure. It's like measuring developer productivity by LoC written.

Yes, it'll measure how much time the candidate spent preparing for the interview, and how well they can jump through hoops. But it'll also deter the actual people you want in the team, the folks who know that leetcode has nothing to do with commercial coding, and see the leetcode test as a sign that your organisation has no clue and a bad management culture.

Re:Jane Street – Our software engineering interviews are cha... by ctmlr on Friday November 13, 2026 @05:02AM (#50481045)
Like ranking chess players on their scrabble game.
Re:Jane Street – Our software engineering interviews are cha... by WalterBright on Friday November 13, 2026 @03:13PM (#50489006)
I heard similar arguments about the SAT as a college entrance requirement. Lots of universities dropped it, including MIT. They found out that SAT scores really did correlate strongly with success at the university, and reinstituted the requirement.

It also reminds me of the "EE"s who carry around a card in their wallet with:

    V = IR
    I = V/R
    R = V/I
written on it.

> But it'll also deter the actual people you want in the team

All the FAANG companies do leetcode testing, so you can write off the high paying jobs.

Re:Jane Street – Our software engineering interviews are cha... by marcus_holmes on Friday November 13, 2026 @10:33PM (#50493548)
I wouldn't want to work in that kind of environment anyway. All that politics and bullshit <shudder>.

I guess that staying as a valid test then - if a company uses leetcode for its interviews, it's probably somewhere I don't want to work.

Re:Jane Street – Our software engineering interviews are cha... by BoingBoomTschak on Friday November 13, 2026 @04:33AM (#50480718)
And if the test is dancing in a monkey outfit while the examiner throws bananas at you like in Zoolander, it's just "fair game", right?

People don't like Leetcode because it's insulting to treat them like freshmen that know nothing but algorithms that related poorly to the job at hand; can't judge them on coding prowesses, for most of them.

Wait, why am I explaining this to you like you're ready to listen beyond your monologue?

Re:Jane Street – Our software engineering interviews are cha... by WalterBright on Friday November 13, 2026 @03:22PM (#50489118)
> People don't like Leetcode because it's insulting to treat them like freshmen that know nothing

I have a friend who is a tech recruiter. There are an awful lot of frauds trying to land programming jobs. Hiring a fraud can cost a company a great deal of money. It shouldn't be any more insulting than applying for an accounting job and the employer does a routine background check to ensure that the candidate is not an embezzler, and not a drug addict.

I worked for a company that hired a coke addict. What a financial disaster that turned out to be.

Re:Jane Street – Our software engineering interviews are cha... by zzrrt on Friday November 13, 2026 @08:10PM (#50492457)
If the bar is as low as complete fraud, the hiring company could save 30+ minutes of engineer time & pay by having HR first verify an accredited degree or work experience. Then do a leetcode as next round if you want.

Having a history of embezzlement or fraud is not in the same ballpark as struggling to whip up a DSA solution. One is a crime and one is a competence issue at best.

Re:Jane Street – Our software engineering interviews are cha... by WalterBright on Friday November 13, 2026 @09:27PM (#50493043)
> by having HR first verify an accredited degree or work experience

Too many frauds have managed to get degrees. I've worked with many of them. Degree'd engineers who cannot use a calculator, who cannot do basic geometry, etc.

Re:Jane Street – Our software engineering interviews are cha... by gib444 on Saturday November 14, 2026 @01:10AM (#50494484)
Please stop sharing stories of coke addict and fraudulent colleagues, you're making me nervous! LOL
Re:Jane Street – Our software engineering interviews are cha... by WalterBright on Saturday November 14, 2026 @02:11AM (#50494771)
They'll do a lot of damage to your company before they get found out.
Re:Jane Street – Our software engineering interviews are cha... by gib444 on Saturday November 14, 2026 @03:25AM (#50495172)
Oh, I was referring to your tine at Boeing
Re:Jane Street – Our software engineering interviews are cha... by WalterBright on Saturday November 14, 2026 @12:46PM (#50499051)
I've worked for several companies.
Re:Jane Street – Our software engineering interviews are cha... by zzrrt on Friday November 13, 2026 @09:15PM (#50492949)
If you're willing to go to any college at all, I think you'll find one that will take you, no matter the score.

If my Googling is correct, you will have chances to retake the strength test. Even if they only give you one try, you know exactly what is tested and can train to the point of near-certainty that you will pass, if your body is capable of it at all. (By contrast, leetcode doesn't care if you could learn a problem, it fails you for not figuring it out on a particular day with a particular interviewer.)

The best jobs can set an arbitrary high bar that loosely correlates with what they want, but it doesn't mean anyone who fails is unqualified to have any software job.

Re:Jane Street – Our software engineering interviews are cha... by WalterBright on Friday November 13, 2026 @09:35PM (#50493131)
> leetcode doesn't care if you could learn a problem

That's where studying it in advance comes in. Like for any test.

> but it doesn't mean anyone who fails is unqualified to have any software job.

It's pointless to argue absolutes when it comes to anything human. Filters do not have to be perfect to be effective.

For example, if I say "people like ice cream" and the pointless reply is "not everybody likes ice cream".

Re:Jane Street – Our software engineering interviews are cha... by yasnu5 on Saturday November 14, 2026 @01:35PM (#50499516)
> If you're willing to go to any college at all, I think you'll find one that will take you, no matter the score.

Indeed, but you're likely to end up a crappy for-profit degree mill that will be more of a negative signal than the positive one you wanted.

Re:Jane Street – Our software engineering interviews are cha... by monksy on Thursday November 12, 2026 @10:37PM (#50477919)
> Leetcode was stupid before LLMs and now it’s even less useful as a signal.

You got my vote right there. I also find it funny that LLMs can easily do leetcode problems, because there were so many examples and easy test cases.

> You do not get a better signal about that from asking harder leetcode problems.

I think this is a thing that needs bigger formatting for this statement or a feature to vote twice.

---

Only response I have to this:

There are many different schools of thought on how to architect systems. In many cases these different opinions don't have a lot of solid backing on why you'd do this. On top of that there is level restrictions that prevent talented individuals from being more influential. I.e. an Architect is less about technical experience and excellence and more about the abiltiy to communciate to high level stakeholds and having systems that can solve the problem [some what].

Re:Jane Street – Our software engineering interviews are cha... by needfish on Friday November 13, 2026 @12:28AM (#50478751)
> Can they translate business requirements into code?

I have been looking for resources that tackle/teach/learn this translation part, but so far hasn't gotten any hits. Can anyone here point me to such a resource, if it exists?

Re:Jane Street – Our software engineering interviews are cha... by satvikpendem on Friday November 13, 2026 @09:05AM (#50483673)
Just build more things, yourself, without AI. Congee up with ideas as they're your business needs and then write code for them.
Re:Jane Street – Our software engineering interviews are cha... by julianlam on Friday November 13, 2026 @12:55PM (#50487182)
Visions of a bunch of engineers workshopping ideas on a cold winter's day over a shared bowl of congee.
Re:Jane Street – Our software engineering interviews are cha... by satvikpendem on Friday November 13, 2026 @04:13PM (#50489740)
Fortunate typo, a better visual than normal.
Re:Jane Street – Our software engineering interviews are cha... by hibikir on Friday November 13, 2026 @12:59AM (#50478943)
Leetcode made perfect sense very early on, before leetcode, the company, existed. It was, at the same time, part a test of smarts, having some capacity to work under pressure, whether a new grad had paid any attention to the data structures and algorithms classes, while we got to see that they could code at all. It was an improvement over whiteboard interviews. And thus, it was what separated a green college student from very high compensation at generous tech companies. The ideal candidate wouldn't even prep for this: they'd just show up, remember the right things, let their talent shine a little, and go past. The questions weren't even that hard back then: You might not even touch what now is a leetcode medium in a typical interview loop. It came from the DSA classes because it would be easy to explain, and something you might recall and implement in 30-50 minutes. It couldn't all just be fizzbuzz.

The problem is that the compensation was so generous, and the kind of questions being asked so public, that your typical somewhat less talented, yet hard working grads would just cram for the interviews, and get past them, thus lowering the value as a filter. Leetcode and the like decided that there was an industry in helping you cram. The filtering got worse and worse, and the companies then decided to keep upping demands, hoping to still get the most talented. But there's nothing in a leetcode interview that cannot be trained. So the metric became the target, and we ended up in the current mess.

Re:Jane Street – Our software engineering interviews are cha... by tirumaraiselvan on Friday November 13, 2026 @04:29AM (#50480688)
> What I want to know is whether someone has basic DSA understanding. Is the person familiar with any programming language. Can they translate business requirements into code? Can they disambiguate weird things PMs say into a viable plan?

I agree with you but this is a "simpler" test with a subjective analysis. Big Tech works at a scale where they probably want to quickly evaluate based on objective results. Did they crack the problem or not? Imagine having a pool of 1000+ candidates for a single role.

Re:Jane Street – Our software engineering interviews are cha... by janalsncm on Friday November 13, 2026 @05:40PM (#50491110)
Let’s say for the sake of argument that 500 of the candidates have the prerequisite programming ability to actually do the job, which they can figure out with a very easy coding exercise, because that’s what the actual job requires.

To filter out the other 499, they can either ask a very difficult question, which based on the previous paragraph we have established is not a useful signal, or we can use a random number generator. Asking a very hard question also rewards luck in a different way, because a candidate who is lucky enough to have recently memorized that question or a similar one will be able to pass it. It does not generalize to anything actually useful for the job.

I submit that the random number generator is a faster and cheaper method.

Re:Jane Street – Our software engineering interviews are cha... by plasticchris on Friday November 13, 2026 @03:22PM (#50489115)
In my experience debugging during a high stakes outage is more about how calm you can remain than anything else, assuming basic competence. Most of the worst problems get caused by panic degrading decision making ability.