At a developer interview lately? What JS questions were you asked?

Additional contextual information may include:

• how much time applicant was given to solve the problem
• whether or not applicant was allowed to use additional resources to solve the problem (i.e. Google)
• job title
• type of interview

Real-world JavaScript interview questions.

---

• Write a function that takes a DOM element and smoothly animates it from its current position to distance pixels to the right over duration milliseconds. Implement the following function, animate(el, milliseconds, distance)

  • Asked as part of a phone screen interview for Facebook position
  • Implement this function without using jQuery or any other third-party libraries

_{^{Discovered 18 December 2019 via Dev.to}}

• Please output the optimal HTML, CSS and JS to render these boxes where clicking on a box changes the color of the box to red.

_{^{Submitted 14 November 2019 via Twitter by Samet M.}}

• Complete the Olympic Challenge.

_{^{Submitted 12 November 2019 via YouTube by RunOS.}}

• Build a todo list with no JavaScript framework. (ex. solution by @xtrp)

  • Applicant had 1 hour to solve
  • Could access the web for help

_{^{Submitted 12 November 2019 via GitHub by miladganjali.}}

• Explain object-oriented programming.

_{^{Submitted 12 November 2019 via GitHub by IlyasEzz.}}

• How to add timestamps in all the console.logs without modifying console logs manually.

_{^{Submitted 9 November 2019 via GitHub by tnvr-bhatia}}

• Complete the Insubuy Code Challenge

  • 48-hour time limit
  • Applicant asked for additional day to complete challenge and was granted extension

_{^{Submitted 8 November 2019 via RTC email by Edward W.}}

• Build a traffic light (semaphore). A black rectangle with 3 circles (lights: red, yellow, green) on it. There can only be one light on at a time. When I click on it, one light turns ON and the others turn OFF. (ex. solution by @xtrp)

  • 20 minute time limit
  • Applicants can use whatever dependencies they want
  • Could access the web for help

_{^{Submitted 8 November 2019 via RTC Discord by Jordan W.}}

• How does garbage collection work in JavaScript?

_{^{Submitted 8 November 2019 via RTC Twitter by Half Maltese Falcon}}

• Explain event bubbling.

_{^{Submitted 8 November 2019 via RTC Twitter by Chris M.}}

• How to sort an array. (ex. solution by @xtrp)

_{^{Submitted 7 November 2019 via RTC Twitter by Christopher D.}}

• How to show an alert box after a mouse click? (ex. solution by @xtrp)

_{^{Submitted 7 November 2019 via RTC Twitter by Leondri S.}}