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My Hack Reactor Interview Process

Hack Reactor is the premier advanced immersive coding school. It was recently voted the best coding school in the world by Switchup and the best coding school in the heart of Silicon Valley by Tech Cocktail. They have a 99% job placement with graduates earning an average of $105k.

What does it take to get accepted into the "Harvard of coding schools?" Well first let me say that you have a 200% better chance of being accepted into Harvard than you do into Hack Reactor. Hack Reactor only accepts 3% of applicants. Here is a summary of my hack reactor interview process.

Hack Reactor Application Process

Almost every coding bootcamp out there promises to take you from nothing to a software engineer in 12 weeks. Based on this promise my mother could qualify to get accepted to any coding school.

Coding schools claim that take you from 0 to 100 in learning how to program. Hack Reactor is different in that they claim to take students from 20 to 120. That distinction is important because it is why Hack Reactor is considered the "best" coding immersive school.

To get into Hack Reactor you will need to already know some basic JavaScript and know how to create small functions. Your knowledge of JavaScript is tested as part of Hack Reactor's application process.

The first step is to complete Hack Reactor's online Admissions Challenge. With this challenge online you can complete it at any time of the day or night.

The Hack Reactor Admissions Challenge will test your knowledge of arrays, functions, objects. Like I said before, to get into Hack Reactor you need to already have a basic knowledge of JavaScript programming. If you are just starting out then you will find this challenge to be almost impossible to complete. Even if you have been studying JavaScript programming for a few months then you will still find this exercise to still be challenging.

Hack Reactor will evaluate your answers to the Admissions Challenge and then determine whether or not they want to let you continue with the interview process. If they feel your skills sets are not ready yet, they will tell you and inform you on where to get more training. You can re-apply after 6 months.

If you answers show a knowledge of JavaScript programming then you will be invited for a technical interview.

Hack Reactor Technical Interview

You will get a chance to pick the date and time for your Hack Reactor Technical Interview. You will be given a link to a calendar with available dates and times. You select the slot that is best for you.

On your scheduled appointment time, your interviewer will connect with you via Skpe. This allows you to do a fact-to-face interview. The first 5-10 minutes will be a casual dialog discussing why you are interested in Hack Reactor.

The next 30-45 minutes of your interview will a coding challenge. You will be given a link to a shared IDE. This IDE will not provide syntax checking or provide color coding that you find in most IDE environments.

The key point here is that you need to be absolutely 100% sure that what you write is fully functional code. If you miss a parenthesis or curly bracket or have a syntax error, your interviewer will notice it and will take a mental note of it. It will be up to you to make sure everything is working correctly.

During your programming assignment you will be asked a series of programming questions.

Hack Reactor Interview Questions

The start of my technical interview was a very simple request to write a function that iterates through all of the members of an array that are passed in as a parameter to the function. Each member of the array would be output to the console. This shows your understanding of writing a very basic function in JavaScript.

Once complete I was asked to expand on that function so that it will work whether an array or an object is passed in as the parameter to the function. To complete this task successfully you need to know how to distinguish whether or not the parameter is an Array or an Object. Based on what it is then you will need to handle them appropriately and output the contents of the array or object to the console.

The next step was to modify the function so that it accepts a second parameter which is a function. The function will be applied to every member of the array or object.

Most people who have studied JavaScript on their own for a few months should be comfortable with the interview process up until this point. The next question I was asked was to show my understanding of closure. Most bootcamps will not cover closure in their curriculum until the 2nd week of instruction. At Hack Reactor you need to show you understand this key concept during your interview process.

The question was to create a new function that would filter all the members of an array based on a function that will pass into this function as a parameter. The function will return a new array with all members that meet the requirement of the function. For example you have a function that takes a number as a parameter and returns whether or not that number is even. You need to write a function called filter that will loop through all members of an array and return the ones that are even.

Your filter function needs to be generic enough that it would allow you to swap out the isEven function parameter with another function called divideBy3 which returns all members that are divisible by 3.

The last question I was asked was to create a function called reduce. This function will reduce an array or object to a single value by repetitively calling iterator(accumulator, item) for each item. Accumulator should be the return value of the previous iterator call.

The Hack Reactor Technical Interview will last one hour.

Getting Accepted to Hack Reactor

The standard response from your interviewer is that you will receive a notice about your application status with 2 weeks after your technical interview is complete. In my case I actually received an email notice stating that I had been accepted the very next day.

by Jennifer Bland

I am a Google Developers Expert. Entrepreneur. Mountain Climber. Neil Diamond fanatic. World traveler. MBA grad. Software Engineer. Interested in hiring me? Contact me at

3 comments… add one
  1. Wow, your resume is so impressive! I found your page because I was looking for help with the TI questions with Hack Reactor. I want to know, when did you enroll? I’m hoping I will be like you someday!


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