Ultimate Guide to Interviewing Backend Developers

Technology
Interviews
Oct, 2023

The role of a Backend Developer is integral to any tech team. Often likened to the director behind the scenes of a film, their main responsibility lies in managing server-side web application logic and integrating the work done by front-end developers.

In this essential role, they are the ones ensuring the system's robustness, efficiency, and seamless flow. As a result, the user experience is significantly enhanced as they meticulously maintain data consistency and integrity.

Moreover, they don't just write lines of code but shape durable, efficient virtual frameworks that breathe life into applications. They are the ones who assure the balance between robustness and performance, positioning themselves as trusted custodians of data consistency and system integrity.

When hiring for a backend developer, you as the hiring manager should be on the lookout for candidates who demonstrate not only the relevant skill set but also a passion for shaping and driving innovative digital solutions. In essence, talent acquisition is as much about fit and potential as it is about the hard skills necessary for backend development.

In this article, you will learn about the high-level day-to-day work of backend developers, the key aspects to consider when interviewing and hiring them, and how to design/structure an interview to increase the chances of success.

A Day in the Life of a Backend Developer

A theoretical ‘day in the life’ of a Backend Developer can be jam-packed with tasks that require not only technical competence but also creative problem-solving and effective collaboration.

1. Coding & Problem Solving: In their daily routine, backend developers often kick-start their day by writing and refining code, focusing on crafting server-side application logic and developing backend components. They also spend significant time utilizing data structures and algorithms. Leveraging these fundamentals of computer science, they strategize methodologies for optimizing system performance and efficiency. When challenges arise, developers display their problem-solving prowess by swiftly developing efficient solutions to maintain the project's progress.
2. System Design & Architecture: Being the architects of the server-side logic, backend developers invest quality time in designing and contemplating system scalability, speed, and resource allocation. With future expansion in mind, they ensure the architecture can handle growth and changes down the line.
3. Collaboration & Communication: Collaboration is a key element of a backend developer's daily routine. They work closely with their front-end counterparts, integrating their outputs into the application, and ensuring seamless synchronization between both ends. They have also mastered the art of communication, articulating complex coding information clearly to foster smooth teamwork across the entire pipeline.
4. Troubleshooting & Optimization: Backend developers frequently juggle troubleshooting challenges, displaying agility and problem-solving skills by resolving issues that demand immediate attention. Additionally, they spend a lot of time managing data caching to speed up the software application. By temporarily storing frequently accessed data, they ensure future data requests are served faster and the system’s performance is enhanced, leading to a more seamless user experience.
5. Security & Caching: As gatekeepers of digital security, backend developers prioritize safeguarding the system and its data against potential threats. This includes implementing encryption mechanisms and setting up authentication protocols. They also play a crucial role in managing data caching and performance. They enhance system performance by implementing effective caching strategies, which include temporarily storing frequently accessed data to ensure quicker delivery on future requests.
6. Cloud Management: For backend developers working with cloud-based applications, their typical day will likely include undertaking deployment activities and optimizing resources. They focus on enhancing performance, security, and cost-effectiveness in their cloud environment, ensuring the system can withstand growth and changes down the line.

The Backend Developer Interview Process

CV Review & Discovery Call (15-30 mins)

Take a closer look at the candidates' resumes or CVs. Of course you should seek out notable experiences, skills, qualifications, and educational background that match the job specifications. More than this, investigate specific aspects such as previous projects, preferred languages and frameworks, experiences in system design, and implemented security measures. It's also advisable to check their familiarity with your industry or related technologies. The discovery call is an ideal forum to clarify any questions about the applicant's qualifications and past experience.

Pre-Screening (30-60 mins)

This preliminary phase often includes a short phone or video call, which all too often are woefully insufficient. Our advice would be to go with a technical screening assessment to qualify your funnel. The aim here is to evaluate candidates' foundational qualifications and technical capabilities in a data-backed, de-biased and scalable way. It's essential to confirm that they possess relevant backend development experience and are proficient with coding and its associated frameworks. Given a sizeable pool of applicants, this initial filtering process is crucial to narrow down prospects to a manageable number and enables your business to practice this at scale.

Here is where Arkiter - an innovative pre-screening interviewing platform - can help you out. As industry-firsts in providing automated System Design assessments, Arkiter provides a comprehensive platform for conducting not only System Design, but Backend Coding, Frontend Project Development, and also Knowledge Pre-screening Interviews. This not only makes the assessment more efficient but also pinpoints the most qualified candidates at an early stage, streamlining the hiring process.

Onsite/Remote Interviews

Onsite/Remote interviews are designed to understand how candidates operate in a team or collaborative environment, and assess how they approach problems, communicate effectively, ask relevant questions, and gather and analyze requirements. This interview must be structured in such a way that it allows the candidate to showcase their full potential. At the same time, the interviewer should gain a clear understanding of the candidate's strengths and weaknesses by the end of the interview. It can be divided into a few parts:

Coding, Problem Solving, Data Structure, and Algorithms (45-60 mins): A significant portion of the interview process entails testing candidates with a coding challenge. Here, their critical problem-solving skills come to the fore, along with their ability to effectively implement data structures and algorithms. This assessment can escalate from a mere question-and-answer style to becoming an interactive session.
This is where Arkiter excels as a platform, providing live interviews where code and architecture can be shared in real-time with immediate results. Both interviewers and interviewees can leverage its features for a seamless interview experience that includes video and audio communication. Post-interview, Arkiter also provides valuable feedback and summarizes the session, aiding in the decision-making process. Also, its extensive question database simplifies and streamlines the session, making it an all-in-one solution.
System Design and Architecture (45-60 mins): Interviews typically evaluate a candidate's proficiency in designing robust, scalable, and efficient systems—a vital skill to ensure hiring choices don't result in potential technical debt up to the hundreds of thousands. This assessment might involve discussing past projects or presenting an impromptu system design challenge.
Arkiter once again can be instrumental during this part of the interview with its live interactive platform. It allows for real-time sharing and evaluation of system designs. Arkiter not only makes this process interactive but also consistent by tying in their broad database, making it an efficient and comprehensive tool.
Software Development Processes & Knowledge Interviews (45-60 mins): It's vital to assess a candidate's proficiency in key software development processes, including Agile, DevOps, and the CI/CD pipeline, to ensure the efficient development lifecycle and automation of your build processes. This discussion can provide insights into how well they could adapt to your development team's methodologies.
Management & Fit Interviews (30-60 mins): The final stage involves a meeting with the hiring manager and/or more senior members of the team. The conversation could center around the candidate's communication abilities, cultural fit, and career aspirations. It presents an opportunity to highlight the attractive aspects of the role at your company, including intriguing projects, avenues for growth, team dynamics, and other positive aspects.

Key Takeaways

Standardized Process: Implementing a standardized process not only helps candidates set expectations about the process, but also increases the chances of success and enables your team to facilitate the process more efficiently. It also minimizes bias and ensures fairness if you have appropriate benchmarking and decision-making criteria in place.
Question Database: A question database is a critical component of a successful interview process. Such a database helps to reduce preparation time for interviewers, shortens the onboarding period for new interviewers, conveys your company's culture and processes to the candidate, tests the candidates on more relevant skills, and increases the likelihood of identifying the best-fit candidates.
While it can be time-consuming to create and may not be at the top of the priority list, this one-time investment can save hours of developer time for each interview. Alternatively, platforms like Arkiter can streamline this process by providing personalized interview design and questions. You can either transition your existing process to Arkiter or use existing industry-specific, personalized questions for the interview.
The feedback loop: The interview process not only assesses a candidate's skills, but it also promotes your company's brand and increases awareness. Providing feedback to candidates creates a positive attitude toward the company, even if a candidate is unsuccessful. A poor interview experience can harm your long-term hiring process and it can be costly to make changes in the future, especially when seeking the best candidates for roles. Having a professional process and feedback loop in place from day one can set your company up for long-term success. While this can often be a time-consuming process, having the right platform and processes in place can make it much more manageable.
One of the key values of Arkiter is respecting everyone’s time, so we are building the feedback process as a part of the interview process. All candidates will receive a feedback report even if they fail the interview. By doing this, we ensure candidates are getting a lot of value out of the process, they know which areas they need to focus on to improve their skills, and your interviews become part of their continuous learning process.