The only real mistake is the one from which we learn nothing.

John Powell

Let’s make one thing clear: being a candidate in an interview is hard. Over your career you will likely participate in many interviews as a candidate, and I can assure you that you likely won’t pass every single one. You aren’t alone here, I myself am no stranger to failed interviews. You can, however, make sure that you are getting something out of every single interview: a new job, exposure to a new problem, a new way to solve a problem, or a better understanding of a problem.

As I have been interviewing candidates recently for a software engineer position at DevResults, I’ve been thinking about what I would do if I had been the candidate in these interviews and I’ve compiled my current thoughts into a few general tips. Some of these are technical interview specific, but the majority are generally applicable to all interviews in general.

Failing a problem is an opportunity to learn

One interview I participated in I was asked to return all permutations of a string. At the time, I had never had to do something like this, and needless to say I didn’t do well on it. After the interview I took the time to really understand the problem and strategies for generating permutations in general, mainly to ensure I wouldn’t ever fail that question again.

Fast-foward to last year, I found myself in a scenario where I did in fact need to generate all possible permutations for a set of data. It made me really appreciate that I had been exposed to that problem in the past from the interview and it was pretty trivial to apply what I had learned to solve the problem.

Most of the time, however, you’ll probably see something you’ve encountered before, or some variation of a known problem. In scenarios like these, there’s often multiple ways to approach a problem and if you didn’t quite get it, the interviewer may explain the solution to you or you can ask what the solution is. If you are able to get the solution to the problem, definitely take the time later to make sure you understand the solution and why it’s the right solution.

If you actually got the solution, but in a non-optimal way (perhaps your solution had poor runtime performance or poor memory usage), be sure to note the problems your algorithm had and research solutions that address those issues.

Ask for feedback

Don’t hesitate to ask for feedback or suggestions on how you did in an interview, but keep your question focussed on your performance. A lot of the time, you won’t get a response for various reasons like company policy prevents the interviewer from giving any feedback to you. Any feedback you are able to get, however, can be very important.

Every interview I conduct I block off an hour and a half which is broken into three parts:

  • The first 10 - 15 minutes I go over the job description and get to know a little more about the candidate
  • The next 45 minutes is dedicated to the candidate answering technical questions
  • The remaining 30 minutes is open question time for the candidate

The vast majority of the time candidates spend about 10 - 15 minutes asking the usual questions like what kind of source control we use, how we do deployments, etc. The other day, howerver, one candidate took full advantage of this time, which I always explicitly say is open Q&A. The candidate asked for feedback on their resume, how well they were communicating while they were coding, how well I could understand them (they were a non-native english speaker), and many other questions.

The insight was extremely valuable for them personally and likely not something any company policy would bar. Before and after each interview, think critically about what things you struggle with and try to get feedback from the interviewer on how they think you did in those regards. This will help you do better in all subsequent interviews.

The only way to get better at interviewing is to do interviews

This seems like common sense advice, but it really is true. If you are having a hard time with interviews, you just need to do more of them. Generally, people only apply to companies or jobs that they are really interested in and waiting to apply to other positions that they would likely be happy with but definitely not their first choice. This is fine, but it can be really demotivating when you don’t make the cut for positions you are really interested in.

When I’m job searching, I tend to take a balanced approach and apply to both types of positions, which allows me to practice interviewing and reduce risk of failing an interview with someplace I really want to work at just because my nerves got to me. It would be unethical to waste someones time by applying to positions you wouldn’t ever want though, so only apply to jobs you can see yourself being happy in.

The last time I went through the hiring process it actually became a little complicated in the end because I ended up facing a situation where I would have to choose between a job I thought I would really like and a position that when I had originally applied I thought I could be happy with but I knew I really wanted after I had met the people involved and learned more about the mission / vision.