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You ask TCP questions to front end developers? It sounds like you are exactly the sort of interviewer this article is calling out. Do you not think that this s

You ask TCP questions to front end developers? It sounds like you are exactly the sort of interviewer this article is calling out. Do you not think that this sort of specialised stuff is really easy to learn? That you should be asking questions to discover programming ability, not pointless reference knowledge in quiz questions? I've debugged complex IIS bugs and found insane bugs in IMAP implementations that were caused by a change in the way Outlook handled the protocol. I did not need to know that before I debugged it. That sort of reference knowledge is rapidly discoverable while you do the debugging. Most of that stuff I will never need to know again.

lambda 12y ago
When I say "TCP questions", I mean that I ask the standard "what happens when you type google.com into your browser and press return," and expect to get them to mention TCP at some point. If they don't, I specifically prompt them, asking what protocols HTTP is built on top of, and how it finds the address of the server to contact. I am not looking for detailed knowledge of receive windows, sequence numbers, or anything of the sort. I consider knowledge that TCP exists, and DNS exists, to be sufficient. And as mentioned repeatedly, even if they know nothing of this question, this is one of many. I want to see if they are the type to dig into the stack and learn more than just their particular domain, but the basic programming exercise and portfolio are the most important things that I look at.
eropple 12y ago
> You ask TCP questions to front end developers? The browser's abstractions are leaky, and given that I tend to work with small teams, an understanding of how the sausage is made is important. And I don't think you can really understand HTTP without understanding TCP at at least a high level. So if I'm hiring for a senior frontend person, I'd expect them to know how it works, and in discussing things (not "technical questions", I just talk to interviewees and go from there) I'd expect some demonstration of things that can make me feel confident that they won't be unduly thrown in day-to-day work by something involving it.
- mattmanser 12y ago
  No they're not! Virtually no javascript developer needs to know about TCP. Ajax doesn't go wrong. Most people abstract it even further using jquery and probably don't really know about how XMLHtttpRequest works. What you've just said is absolute bullshit. Complete and utter horseshit. It's an artificial barrier you've erected to filter out people who aren't like you. How wrong would you have had to write your javascript that you'd need to start knowing the specifics of two levels of abstraction down? I am completely flabbergasted that a professional programmer would claim they needed a high level of understanding of TCP to write javascript.
  - ac2u 12y ago
    I think you're misinterpreting the use of "high level" here. It's not that the candidate needs "a high level of understanding", it's that they need "a high level understanding". "High" here is in reference to the level of abstraction. A high level understanding could mean something as simple as understanding the request-acknowledge nature of TCP, as opposed to the 'fire and forget' mechanism of UDP. As to the claim that virtually no javascript developer needs to know TCP, that becomes less of a truth the closer you get to experimenting with tech like websockets, which is increasingly becoming part of javascript developers' jobs. I think you're latching onto a narrative that you already made up about the poster before you even began this debate. There's a large leap between what the poster is saying "I ask a wide range of questions to catch red flags if they get all wrong", and what you're saying "the poster is saying that javascript devs NEED to know TCP! Obviously an elitist filtering mechanism!".
    - eropple 12y ago
      Yes, this. Thank you for a reasonable reply to an unreasonable post. (And as to the rest of his very angry post, I'm not a front-end developer, I do platform work and what some folks call devops. I can tell you exactly how XMLHttpRequest works, in detail, with diagrams. I can also go on at length about the DOM, the travishamockery of CSS, as much JavaScript minutiae as one would like...I think a basic understanding of the world around us is important to being good at things. Being "a front-end programmer" doesn't mean you should be so incurious as to not know how things you don't touch every day but directly inform the things that you do actually work.)

lambda 12y ago

When I say "TCP questions", I mean that I ask the standard "what happens when you type google.com into your browser and press return," and expect to get them to mention TCP at some point. If they don't, I specifically prompt them, asking what protocols HTTP is built on top of, and how it finds the address of the server to contact. I am not looking for detailed knowledge of receive windows, sequence numbers, or anything of the sort. I consider knowledge that TCP exists, and DNS exists, to be sufficient. And as mentioned repeatedly, even if they know nothing of this question, this is one of many. I want to see if they are the type to dig into the stack and learn more than just their particular domain, but the basic programming exercise and portfolio are the most important things that I look at.

eropple 12y ago

> You ask TCP questions to front end developers? The browser's abstractions are leaky, and given that I tend to work with small teams, an understanding of how the sausage is made is important. And I don't think you can really understand HTTP without understanding TCP at at least a high level. So if I'm hiring for a senior frontend person, I'd expect them to know how it works, and in discussing things (not "technical questions", I just talk to interviewees and go from there) I'd expect some demonstration of things that can make me feel confident that they won't be unduly thrown in day-to-day work by something involving it.

mattmanser 12y ago
No they're not! Virtually no javascript developer needs to know about TCP. Ajax doesn't go wrong. Most people abstract it even further using jquery and probably don't really know about how XMLHtttpRequest works. What you've just said is absolute bullshit. Complete and utter horseshit. It's an artificial barrier you've erected to filter out people who aren't like you. How wrong would you have had to write your javascript that you'd need to start knowing the specifics of two levels of abstraction down? I am completely flabbergasted that a professional programmer would claim they needed a high level of understanding of TCP to write javascript.
- ac2u 12y ago
  I think you're misinterpreting the use of "high level" here. It's not that the candidate needs "a high level of understanding", it's that they need "a high level understanding". "High" here is in reference to the level of abstraction. A high level understanding could mean something as simple as understanding the request-acknowledge nature of TCP, as opposed to the 'fire and forget' mechanism of UDP. As to the claim that virtually no javascript developer needs to know TCP, that becomes less of a truth the closer you get to experimenting with tech like websockets, which is increasingly becoming part of javascript developers' jobs. I think you're latching onto a narrative that you already made up about the poster before you even began this debate. There's a large leap between what the poster is saying "I ask a wide range of questions to catch red flags if they get all wrong", and what you're saying "the poster is saying that javascript devs NEED to know TCP! Obviously an elitist filtering mechanism!".
  - eropple 12y ago
    Yes, this. Thank you for a reasonable reply to an unreasonable post. (And as to the rest of his very angry post, I'm not a front-end developer, I do platform work and what some folks call devops. I can tell you exactly how XMLHttpRequest works, in detail, with diagrams. I can also go on at length about the DOM, the travishamockery of CSS, as much JavaScript minutiae as one would like...I think a basic understanding of the world around us is important to being good at things. Being "a front-end programmer" doesn't mean you should be so incurious as to not know how things you don't touch every day but directly inform the things that you do actually work.)