Welcome to our comprehensive three-part blog series on engineering interview preparation for Opn. If you're aspiring to join Opn, a leading payment solutions technology company, and want to ace your engineering interview, you've come to the right place. In this series, we will guide you through the various aspects of Opn's technical interview process, providing valuable insights, tips, and strategies to help you succeed.

Whether you're a seasoned engineer or just starting your career, this blog series will equip you with the knowledge and skills necessary to excel in your interview and showcase your potential as a valuable addition to Opn's engineering team.

So, let's dive in and get you ready for success!

• In Part 1 of our engineering interview preparation blog series, we will focus on laying a strong foundation for understanding Opn's tech stack and specific tools used. We will discuss the importance of familiarizing yourself with the technologies and tools Opn utilizes, as well as provide an overview of the technical interview process at Opn. We will delve into the scope of the technical interview, including tips for navigating the coding round and design rounds. By the end of this section, you will have a solid understanding of the technical aspects you need to focus on to excel in Opn's engineering interview.

• Moving on to Part 2 of our blog series, we will shift our attention to behavioral questions and what to expect during the interview process. We will explore the significance of communication skills and the role they play in showcasing your potential as a valuable team member at Opn. Additionally, we will emphasize the importance of demonstrating teamwork and problem-solving skills during the interview process. This section will provide you with valuable insights and strategies to effectively handle behavioral questions and showcase your interpersonal skills, ultimately increasing your chances of success.

• In the final part of our engineering interview preparation blog series, we will wrap up the series by summarizing the key takeaways and providing a comprehensive review of the topics covered in Parts 1 and 2. We will also offer additional tips and resources to further enhance your interview preparation. By the end of this series, you will be well-equipped with the knowledge and strategies necessary to approach an engineering interview at Opn with confidence and professionalism. So, let's prepare you to shine in your interview and take the first step toward a rewarding career at Opn!
  
  

My name is Bernard, and I’ve several years of experience as a technical recruiter in the information technology industry. Currently, I work as a technical talent acquisition partner at Opn. The main responsibilities I hold at Opn include the attraction of quality technical talents via several recruitment marketing schemes; partnering with different technical divisional and sub-divisional stakeholders to discuss hiring requirements; preparing candidates to align with our interview process; fulfilling software engineering recruitment needs; and ensuring a smooth hiring process with an emphasis on candidate experience. One of the many attractions of my work at Opn is the experience of partnering with both local and global tech talents and preparing them for interviews. Therefore, I will be sharing tips and guidance on preparing for a software engineering technical interview at Opn. The objective is to help you feel more confident in the entire interview process while increasing your chances of success in landing a software engineering job with us.

Technical rounds are the most challenging parts of the software engineering interview process. I’ve noticed many software engineers dropping out of the process from the introductory round to the final round, with the majority of them dropping at the technical round. Causes may include the candidate's lack of preparation, lack of enough sleep the night before, or the inability to communicate their thought process clearly during the technical round. Of course, not all software engineers who fail technical rounds are incapable of the jobs they apply for. However, since the technical round plays an outsized role in hiring decisions, failure to prepare is preparing to fail.

Importance of Understanding Opn's Tech Stack and Specific Tools Used

Preparing for technical interviews can be challenging and time-consuming for software engineers. What you want to do first is understand Opn’s technical stack either through the job description, in which it is usually mentioned, or during the preliminary call with the recruiter. We utilize various technical stacks such as Ruby, Go, TypeScript, JavaScript, and React for our projects. At the same time, our services are hosted on AWS.

Understanding the tools that are used is important to your preparation. For example, the Leetcode platform is used for the online coding round. We allow you to pick a programming language you are most comfortable with during the coding challenge. We also use Google Jamboard for the design round. All the rounds are conducted online.

Overview of the Technical Interview Process at Opn

Our interview process at Opn is straightforward, and we ensure you are well-prepared for the technical rounds. The process is clearly communicated to you by our talent acquisition partner early in the interview process. The technical interview consists of two rounds: (a) the coding round and (b) the design round, each lasting one hour. You will have 50 minutes to respond to questions and 10 minutes for Q&A.

Depending on the availability of both the candidate and the interviewer, these rounds may take place on different days. The coding round focuses on data structures and algorithms, while the design round focuses on architecture and system design. The difficulty of the questions will vary based on the seniority of the position you applied for, ranging from medium to hard.

Scope of the Technical Interview Round Tips

• Coding round

The coding round questions target two areas of computer science knowledge with which we expect you to be intimately familiar with (a) data structures; and (b) algorithms. Since data structures are a huge topic in computer science, your best bet is to practice data structure exercises on Leetcode.

Be sure to have a good awareness of the time and space complexities of various algorithms, as many engineers tend to struggle here. Perhaps, it has been a long time since you last touched them, so take enough time to go back to practice. Understand the concepts, study the syntax very carefully, and get familiar with different ways of responding to the questions.

During the interview, before attempting to write your solution, you may want to first clarify the question with the interviewer, analyze the problem, and detail the logic and why you will decide on this approach to solving the problem. The more you apply this format, the less stressful the interview will seem. It is important to point out that the interviewers want you to do well and are there to support you.

The whole idea for you is to show the interviewer how you think, communicate, and whether you can solve problems. By doing so, you have opened the floor to engage more with the interviewer and welcome any suggestions associated with tackling the coding problems.

• Design round

Most of the time, the design round is a reference point to determine the level of an engineering candidate. This round aims to evaluate a candidate's skill at designing real-world software systems. There are several resources online that could aid you in preparing for this particular round, including enrolling in an online system design course or following a design system instructor on social media platforms.

Design round interviews are usually not as direct as coding interviews because they tend to focus on real-world software systems where your experience and learnings play a huge part in coming out successfully.

The questions asked at Opn design interviews are constantly changing and can be derived from any real-world software solution. Still, it is common among our interviewers to ask questions around the topic of payment gateways as this will be most relevant to your day-to-day work.

In the design round, candidates are encouraged to provide their ideal software architecture design to implement a hypothetical service under certain constraints. Questions can include:

• Design a payment system for an e-commerce platform.

• Design a map for a motorcycle tracking system?

• Design an API for Google Maps?

• Design a payment gateway API?

• Design a rider and driver matching system.

• Design an e-commerce vendor acquisition and customer platform system.

• Design a system that allows each user to send messages or images.

When being interviewed and during coding rounds, it's helpful to repeat the questions to the interviewer to ensure that both of you are on the same page. If you don't understand, feel free to ask the interviewer to repeat or rephrase the question. You may want to structure your answers before solving the problems to create a coherent format in your answers.

In conclusion, preparing for a software engineering technical interview at Opn requires a thorough understanding of Opn's tech stack and specific tools used. Familiarizing yourself with the technologies mentioned in the job description or during preliminary discussions with the recruiter is essential.

• Additionally, being aware of the tools utilized, such as the Leetcode platform for the coding round and Google Jamboard for the design round, will enhance your preparation.

• The technical interview process at Opn consists of coding and design rounds, each lasting one hour. To navigate the coding round successfully, practice data structure exercises on Leetcode.com; understand time and space complexities, and communicate your thought process clearly to the interviewer.

• For the design round, focus on real-world software systems, leverage online resources, and be prepared to provide architectural designs based on hypothetical scenarios.

By following these tips and demonstrating your problem-solving skills, communication abilities, and teamwork, you will increase your chances of succeeding in the software engineering interview at Opn.

Stay tuned for Part 2 of this blog series, where we will delve into behavioral questions, communication skills, and the importance of teamwork and problem-solving. Get ready to take your interview preparation to the next level!