Key Questions to Ask a Software Engineer in an Interview

Imagine this: You’ve narrowed down your list of potential candidates to one or two. They’ve got the resume, the experience, and the certifications. But here’s the million-dollar question: how do you ensure that this is the person who will drive innovation, fit in with your team, and solve the real problems your business is facing?

You’ve got to ask the right questions. Software engineers can be a critical asset, but to uncover their true potential, you need to go beyond the standard "What are your strengths and weaknesses?" You want to dig into their problem-solving abilities, team dynamics, and adaptability. Let’s dive right into it.

1. Can you walk me through a project where you faced significant challenges and how you overcame them?

Why ask this?
This question doesn’t just give insight into their technical chops; it offers a glimpse into how they handle stress, deadlines, and unexpected problems. Do they rise to the occasion or crumble under pressure?

What to look for in their response?

• Critical thinking: How did they approach the problem? Did they identify the core issue before attempting a fix?
• Collaboration: Did they seek help from teammates, or did they try to solve everything solo?
• Learning mindset: Did they come out of the situation with new knowledge or strategies they can apply to future problems?

2. What is the most difficult bug you’ve had to resolve, and how did you handle it?

Why ask this?
Bug-fixing is the bread and butter of most software engineering roles. Bugs can range from simple fixes to mind-bending issues that take days or even weeks to resolve. You want someone who knows how to handle these challenges without becoming frustrated or giving up.

What to look for in their response?

• Persistence: Did they try multiple approaches?
• Efficiency: How did they manage their time when stuck on a difficult bug?
• Resourcefulness: Did they use any specific debugging tools or consult the broader developer community?

3. Tell me about a time when you had to make a decision without having all the necessary information.

Why ask this?
Engineering is often about making the best decision with the information available at the time. How does this candidate deal with uncertainty? This question sheds light on their decision-making process under ambiguous conditions.

What to look for in their response?

• Risk management: Did they take calculated risks or leap without considering consequences?
• Adaptability: How did they pivot when new information became available?

4. How do you prioritize tasks when working on multiple projects simultaneously?

Why ask this?
You want to assess how they juggle responsibilities. Most engineers will have competing demands for their time and attention, so their ability to prioritize effectively is critical.

What to look for in their response?

• Time management skills: Are they using frameworks like Agile, Kanban, or Pomodoro techniques to organize their time?
• Task prioritization: Do they focus on tasks with the highest impact or those that are easiest to complete?

5. How do you stay updated with new technologies and programming languages?

Why ask this?
The tech industry evolves at a rapid pace. You need to hire someone who isn’t just skilled in today’s tech stack but is constantly learning to adapt to new tools and methods.

What to look for in their response?

• Commitment to learning: Are they following blogs, podcasts, attending conferences, or taking online courses?
• Proactive vs. reactive learning: Are they learning new technologies in response to a project’s requirements, or are they consistently looking ahead to what’s coming next?

6. Tell me about a time you had to work with a difficult team member. How did you handle it?

Why ask this?
Soft skills can be just as important as technical expertise. No matter how brilliant a candidate may be, if they can’t communicate well or handle interpersonal conflicts, it will create problems within the team.

What to look for in their response?

• Conflict resolution skills: Did they address the issue head-on or let it fester?
• Empathy: Did they try to understand the other person’s perspective before reacting?
• Professionalism: Were they able to maintain a positive working relationship despite the challenges?

7. How do you test and ensure the quality of your code?

Why ask this?
Quality assurance is vital in any software engineering role. Mistakes in code can lead to massive downtime, security vulnerabilities, or loss of data. You need someone who is rigorous in testing and has a clear process for ensuring that their code meets quality standards.

What to look for in their response?

• Testing methodologies: Are they using unit tests, integration tests, or TDD (Test-Driven Development)?
• Automation tools: Are they familiar with Continuous Integration/Continuous Deployment (CI/CD) pipelines?
• Attention to detail: Do they review their code before submitting it for peer review?

8. How would you explain a technical concept to someone without a technical background?

Why ask this?
A great engineer can break down complex concepts for non-technical stakeholders. Whether it’s explaining a software feature to the marketing team or helping a client understand a timeline shift, communication skills are crucial.

What to look for in their response?

• Clarity: Can they simplify without being condescending?
• Patience: Are they comfortable walking through a concept multiple times if needed?

9. What’s your approach to debugging large, unfamiliar codebases?

Why ask this?
In many companies, especially startups, engineers often have to dive into codebases they didn’t write. You need to see how they handle the overwhelming task of deciphering someone else’s logic.

What to look for in their response?

• Process: Do they have a systematic approach to break down large chunks of code?
• Tool usage: Are they familiar with version control systems, profiling tools, or static code analyzers that can speed up the process?

10. If you had to build a software solution from scratch, how would you approach the project?

Why ask this?
You want to assess their architecture and planning skills. How do they envision and execute projects, from conception to completion? This is a chance to see how they design solutions and think through challenges before writing any code.

What to look for in their response?

• Planning: Do they break the project down into milestones or sprint cycles?
• Technology stack: Do they choose technologies based on the problem at hand or just their personal preference?
• Scalability: Are they thinking about future needs and how their solution will grow over time?

Bonus: What’s your favorite language/technology and why?

Why ask this?
Passion is key. By asking this question, you’re not just learning about their preferred tools but also gauging their enthusiasm for their work. A passionate engineer will go above and beyond to improve their skills and contribute meaningfully to projects.

What to look for in their response?

• Curiosity: Are they continuously exploring new tools and languages?
• Depth of knowledge: Do they have a nuanced understanding of their favorite technology's strengths and weaknesses?

Wrapping it Up:

An interview is an opportunity to dig beneath the surface and truly understand what makes an engineer tick. By asking the right questions, you can ensure that you’re not just hiring someone with the right skills but also someone who will bring value, insight, and innovation to your team.