Вопросы, которые задают при приеме на работу у WEB разработчика/ . Интервью.
Front-end Job Interview Questions
A while ago, a group of very intelligent and experienced Front-end Developers got together and created a list of great Front-end focused job interview questions. This group consisted of @bentruyman,@ajpiano, @paul_irish, @SlexAxton, @boazsender, @miketaylr, @iansym,@vladikoff and @gf3. Since it’s creation, I’ve expanded to this list and happen to use it to help friends prepare for interviews (like my good friend Wes Bos / @wesbos) or to interview developers myself.
To note, I think that it’s only necessary to choose a handfull of questions from this list to get a good sense of a candidates capabilities and fit. The most telling questions often relate to what a person does in their free time. Asking about Twitter & Github Accounts, RSS feeds, Personal Blogs and general community involvement will tell you a lot about whether or not this person will stay up-to-date and is passionate about their work. The last group of questions will definitely let you know if the person’s got a sense of humour.
Hope this list helps some people and, if you do use it, make sure to give credit to the folks that contributed (listed above).
Note: I’ve posted this document up on Github so that you can add to it if you want. Here’s the link: https://github.com/darcyclarke/Front-end-Developer-Interview-Questions
JOB INTERVIEW QUESTIONNAIRE
General Questions:
- Are you on Twitter?
- If so, who do you follow on Twitter?
- Are you on Github?
- If so, what are some examples of repos you follow
- What blogs do you follow?
- What version control systems have you used?
- What is your preferred development enviroment? (OS, Editor, Browsers, Tools etc.)
- Can you describe your workflow when you create a web page?
- Can you describe the difference between progressive enhancement and graceful degradation?
- Bonus points for the answer “no one can”
- Extra bonus points for describing feature detection
- Explain what “Semantic HTML” means.
- What does “minification” do?
- Why is it better to serve site assets from multiple domains?
- How many resources will a browser download from a given domain at a time?
- If you have 8 different stylesheets for a given design, how would you integrate them into the site?
- Looking for file concatenation.
- Points off for
@import
, unless it works in conjunction with a build system.
- If you jumped on a project and they used tabs and you used spaces, what would you do?
- Write a simple slideshow page
- Bonus points if it does not use JS.
- What tools do you use to test your code’s performance?
- If you could master one technology this year, what would it be?
- Name 3 ways to decrease page load. (perceived or actual load time)
- Explain the importance of standards.
HTML-Specific Questions:
- What’s a
doctype
do, and how many can you name? - What’s the difference between standards mode and quirks mode?
- What are the limitations when serving XHTML pages?
- Are there any problems with serving pages as
application/xhtml+xml
?
- How do you serve a page with content in multiple languages?
- Can you use XHTML syntax in HTML5? How do you use XML in HTML5?
- What are
data-
attributes good for? - What are the content models in HTML4 and are they different in HTML5?
- Consider HTML5 as an open web platform. What are the building blocks of HTML5?
- Describe the difference between cookies, sessionStorage and localStorage.
JS-Specific Questions
- Which JavaScript libraries have you used?
- How is JavaScript different from Java?
- What are
undefined
and undeclared
variables? - What is a closure, and how/why would you use one?
- Your favorite pattern used to create them? argyle (Only applicable to IIFEs)
- What’s a typical use case for anonymous functions?
- Explain the “JavaScript module pattern” and when you’d use it.
- Bonus points for mentioning clean namespacing.
- What if your modules are namespace-less?
- how do you organize your code? (module pattern, classical inheritance?)
- What’s the difference between host objects and native objects?
- Difference between:
1234
function Person(){}
var person = Person()
var person = new Person()
- What’s the difference between
.call
and .apply
?
- explain
Function.prototype.bind
?
- When do you optimize your code?
- Can you explain how inheritance works in JavaScript?
- Bonus points for the funny answer: “no one can”
- Extra bonus points if they take a stab at explaining it
- When would you use
document.write()
?
- Correct answer: 1999 – time to weed out the junior devs
- What’s the difference between feature detection, feature inference, and using the UA string
- Explain AJAX in as much detail as possible
- Explain how JSONP works (and how it’s not really AJAX)
- Have you ever used JavaScript templating, and if so, what/how?
- Explain “hoisting”.
- What is FOUC? How do you avoid FOUC?
- Describe event bubbling.
- What’s the difference between an “attribute” and a “property”?
- Why is extending built in JavaScript objects not a good idea?
- Why is extending built ins a good idea?
- Difference between document load event and document ready event?
- What is the difference between
==
and ===
?
- Explain how you would get a query string parameter from the browser window’s URL.
- Explain the same-origin policy with regards to JavaScript.
- Explain event delegation.
- Describe inheritance patterns in JavaScript.
- Make this work:
1
[1,2,3,4,5].duplicator(); // [1,2,3,4,5,1,2,3,4,5]
- Describe a strategy for memoization in JavaScript.
- Why is it called a Ternary statement, what does the word “Ternary” indicate?
- What is the arity of a function?
JS-Code Examples:
1
~~3.14
Question: What value is returned from the above statement?
Answer: 3
1
"i'm a lasagna hog".split("").reverse().join("");
Question: What value is returned from the above statement?
Answer: “goh angasal a m’i”
1
( window.foo || ( window.foo = "bar" ) );
Question: What is the value of window.foo?
Answer: “bar”
123456
var foo = "Hello";
(function() {
var bar = " World";
alert(foo + bar);
})();
alert(foo + bar);
Question: What is the outcome of the two alerts above?
Answer: ”Hello World” & ReferenceError: bar is not defined
jQuery-Specific Questions:
- Explain “chaining”.
- What does
.end()
do?
- How, and why, would you namespace a bound event handler?
- What is the effects (or fx) queue?
- What is the difference between
.get()
, []
, and .eq()
?
- What is the difference between
.bind()
, .live()
, and .delegate()
?
- What is the difference between
$
and $.fn
? Or just what is $.fn
.
- Optimize this selector:
1
$(".foo div#bar:eq(0)")
CSS-Specific Questions:
- Describe what a “reset” CSS file does and how it’s useful.
- Describe Floats and how they work.
- What are the various clearing techniques and which is appropriate for what context?
- Explain CSS sprites, and how you would implement them on a page or site.
- What are the differences between the IE box model and the W3C box model?
- What are your favourite image replacement techniques and which do you use when?
- CSS property hacks, conditionally included .css files, or… something else?
- How do you serve your pages for feature-constrained browsers?
- What techniques/processes do you use?
- What are the different ways to visually hide content (and make it available only for screenreaders)?
- Have you ever used a grid system, and if so, what do you prefer?
- Hav you used or implement media queries or mobile specific layouts/CSS?
- Any familiarity with styling SVG?
- How do you optimize your webpages for print?
- What are some of the “gotchas” for writing efficient CSS?
- Do you use LESS?
- How would you implement a web design comp that uses non-standard fonts? (avoid mentioning webfonts so they can figure it out)
- Explain how a browser determines what elements match a CSS selector?
Optional fun Questions:
- What’s the coolest thing you’ve ever coded, what are you most proud of?
- Do you know the HTML5 gang sign?
- Are you now, or have you ever been, on a boat.
- Tell me your favorite parts about Firebug / Webkit Inspector.
- Do you have any pet projects? What kind?
- Explain the significance of “cornify”.
- On a piece of paper, write down the letters A B C D E vertically. Now put these in descending order without writing one line of code.
- Wait and see if they turn the paper upside down
- This should make the laugh and is a fine way to relieve some tension at the end of the interview.
- Pirate or Ninja?
- bonus if it’s a combo and a good reason was given (+2 for zombie monkey pirate ninjas)
- If not Web Development what would you be doing?
- Where in the world is Carmen Sandiego?
- (hint: their answer is always wrong)
- What’s your favorite feature of Internet Explorer?
tags: development / front-end / interview / job / questions