Interview questions to ask software developers

You’ve written the job description; you’ve shortlisted the candidates and now it’s time to get the software developers in for an interview, but what should you ask? How can you get the most out of a candidate? What will give you a true representation of their capabilities and work ethic? Here’s a few techniques some of our industry leaders are using:

Competency questions

What’s the hardest thing you’ve ever done?
Open-ended interview questions are designed to give candidates the opportunity to showcase what they have achieved; they can demonstrate their capabilities and show how they might overcome a challenging problem.

What’s a fun project that you’ve worked on recently? What was your role in it?
This is how you can find out what the candidate is passionate about and what part of the role they really enjoy. You can use this to work out where they might fit in the team and how they’d work with your existing developers.

What do you know about the company?
A basic question but great for finding out if a candidate really wants the job. If they can’t give a comprehensive answer, then they haven’t done their research.  Perhaps they’re interviewing in several places or just lazy (not what you want from a potential hire).

Describe the process you use for writing a piece of code, from requirements to delivery
There are three benefits to this question:

1. Seeing how well they think on their feet. Yes, this is something they would have done several times. But how well can they communicate this?
2. Demonstrating their organisational skills. Failing to prepare is preparing to fail.
3. Insight to how they work and adhere to processes

Technical challenges

The software developers you are interviewing have given you some pretty good answers, you think they’ll be a good fit in the team but how do you assess whether they’re able to code to the standard that your team does? You’ve got a few options:

Written tests/remote tests
This can either be a test they complete at the interview or emailed to the candidate to be completed from the comfort of their own home. Usually something that takes 2-3 hours would be appropriate, if it is going to take a lot longer you might find candidates lose interest.

GitHub/GitLab
While this is not specifically a technical challenge it does allow you to assess their capabilities. You’ll not only get to see examples of their work, but you can see what they’re working on and how often they code in their spare time.

Whiteboard exercise
Giving a candidate a tech problem and asking them to work out their code and explaining the solution will test their communication and problem-solving skills. This is not as effective for the more introverted candidates who may find it daunting, so it is best used for roles where these skills are vital.

Paired programming
This is an agile software development technique in which two programmers work at one workstation. The candidate must complete the task (such as building something in JavaScript for example) while interacting and explaining what they’re doing, as they do it.

When it comes to technical tests some hiring managers ask candidates to complete a practical assessment prior to a face-to-face interview, where you can then ask questions related to the technical test, while other hiring managers choose to finish the recruitment process with a technical test to differentiate between the best candidates.

The key to conducting a successful software developer interview is preparation; researching what you need from the recruitment process, what stages would be appropriate and how you are going to fairly assess each candidate. In a competitive market where software developers are sought-after you want to streamline your recruitment as much as possible to ensure your interviewees don’t get snapped up by another company.

We speak to developers every day and know what they like/dislike about job interviews and how best to structure your interview process to maintain a positive candidate experience. If you’re unsure about your recruitment process or what interview questions to ask software developers, please get in touch.