Use these questions to identify a candidate’s technical knowledge and abilities
Use these questions to determine how a candidate handled situations in the past
Use these questions to assess a candidate’s personal traits and cognitive skills
Why this matters:
A full stack engineer is faced with many considerations before settling on a tech stack. Their answer will show how they think about choosing technologies. This question is also an opportunity for you to gauge how much experience they’ve had with the available tech—and which tool sets they prefer.
What to listen for:
- Candidates should mention at least one major technology, like CSS, Ruby, or JavaScript.
- If the candidate utilized pre-determined company standards to make their choices, dig deeper to see if they would have approached anything differently—and why.
Why this matters:
There are many ways to store passwords, but only a few approaches are considered absolutely secure from the front to the back end. Ideally, the candidate will be able to explain which specific security features are essential. Their answer to the second part of the question will shed light on how user data is protected from interface to databases.
What to listen for:
- Strong answers may mention how the candidate handled this scenario in a prior role.
- Listen for references to plain text passwords, cryptographic hash functions (MD5 and SHA1), and salt.
Why this matters:
Being able to answer a complex question in a short amount of time is not easy. A highly qualified full stack engineer won’t flinch. They should be able to describe their approach in a clear, concise way, while shedding light on their industry knowledge. Those who get flustered or have a difficult time may not be up for a challenge.
What to listen for:
- Look for answers that discuss specific development concepts, such as user experience, bugs, and other terminology.
- If the candidate pushes back with a lot of questions, this may be a red flag that they’re not ready for a challenge.
Why this matters:
Most full stack engineers would have a very difficult time choosing one language among the many options available. Over their career, they will find that one language may be better suited to a project than another. Their answer will show how much they’re engaged with the industry—and how deep their passion runs for their craft.
What to listen for:
- Struggling to answer or an inability to choose are good signs.
- A strong answer may reference past projects and any thoughts behind their programming choices.
Why this matters:
A developer who can assess how a website or program should look and feel, while also understanding the technical limitations of the implementations, can see the big picture. Full stack developers are valuable to a team because they can address and discuss both aspects of the web development process—and bridge any disconnect.
What to listen for:
- Listen for references to both front end and back end development projects.
- Candidates should convey the importance of being versatile and planning time wisely.
Why this matters:
Quality assurance is integral to the success of every implementation. Development projects often require a team of minds, and pointing out bugs or flaws is part of the territory. Not only will the answer demonstrate how much the candidate values precision, it will show how comfortable they are working with others.
What to listen for:
- Listen for concrete details of their approach, how the colleague received the news, and what steps they took toward a solution.
- Strong answers will include references to this being a teachable moment for the greater good.
Why this matters:
This question is designed to demonstrate the scope of the candidate’s skill set and how comfortable they are juggling projects. The best full stack engineers can easily jump from coding a landing page to fixing a networking issue to meeting with clients in one day. Having the knack for planning and time management is key.
What to listen for:
- A great answer mentions the advantage of seeing the “bigger picture” by knowing both design and architecture.
- Listen for indications they enjoy the range of tasks required by a role—and aren’t thrown by multiple projects or deadlines.
Why this matters:
The world of development is ever-changing. The candidate should have a current knowledge of the field and a desire to keep learning as it evolves. If they’re not in tune with the tech community, working on independent projects, or brushing up on their skills, they may not be a forward-thinking employee.
What to listen for:
- Look for answers that describe meetups, personal projects displayed in GitHub, or online learning platforms.
- Any mention of a lack of time to do so is a red flag that they can’t multitask and/or have no passion for the industry.
Why this matters:
Development can be a complex minefield, so nearly all full stack developers have had their share of barriers and roadblocks. The details of this answer are not as important as the willingness to discuss flaws or struggles. Essentially, if they haven't faced a challenge, they might not be as experienced as you need.
What to listen for:
- Listen for indications they have a grasp on why they had difficulty, what they learned, and how they used the experience to move forward.
- Strong answers will mention asking for help or referring to their toolbox of resources for assistance.
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