Optiver Software Engineer Interview Questions + Guide in 2025

Optiver is a tech-driven trading firm and leading global market maker, renowned for leveraging technology to optimize trading strategies and enhance market efficiency.

As a Software Engineer at Optiver, you will be a key player in designing, developing, and maintaining robust trading systems that directly impact financial markets. This role requires a strong understanding of computer science fundamentals, along with experience in programming languages such as C++, Python, or C#. You will collaborate closely with traders and researchers to tackle complex problems, ensuring that the systems are responsive to market events in microseconds and capable of handling large sets of financial instruments with minimal error. Your responsibilities will include establishing technical direction for major initiatives, maintaining high coding standards, and continually refining the infrastructure to meet the dynamic needs of the firm.

Optiver values engineers who are not just coders but problem solvers who apply a disciplined and scientific approach to their work. A successful candidate will demonstrate innovative thinking, a passion for clean, well-architected systems, and a desire to continuously improve in a rapidly evolving environment. This guide will help you prepare effectively for the interview process by providing insights into the expectations and challenges of the role, enabling you to present yourself as the ideal candidate for Optiver.

Founded over three decades ago, Optiver has established itself as a leader in its field, recognized as a technology-driven leading trading company and a global market maker. As the financial firm continues to evolve, there is a growing demand for software engineers to create and implement trading systems, with the Optiver HackerRank assessment playing a crucial role in their hiring process.

If you’re currently considering applying for this role, then this Optiver Software Engineer Interview Guide is for you. It’s structured to ensure that by the time you finish, you’ll be more than prepared to face Optiver’s interview process confidently.

In this section, we’ll review the various interview questions that might be asked during a Software Engineer interview at Optiver. The interview process will assess your technical skills, problem-solving abilities, and cultural fit within the organization. Candidates should be prepared to demonstrate their understanding of software engineering principles, coding proficiency, and ability to work collaboratively with traders and other engineers.

Technical Skills

1. What is your experience with C++, Python, or C#?

Optiver values strong programming skills, so be prepared to discuss your proficiency in these languages and any relevant projects you've worked on.

How to Answer

Highlight specific projects where you utilized these languages, focusing on the challenges you faced and how you overcame them.

Example

“I have extensive experience with C++ and Python, having developed a trading simulation tool in C++ that processed real-time market data. This project required optimizing performance to handle high-frequency data, which I achieved by implementing efficient algorithms and data structures.”

2. Can you explain the concept of microservices and how they apply to trading systems?

Understanding modern software architecture is crucial for this role.

How to Answer

Discuss the benefits of microservices, particularly in terms of scalability and maintainability, and relate it to trading systems.

Example

“Microservices allow for independent deployment and scaling of different components of a trading system, which is essential for handling varying loads during market fluctuations. For instance, separating the order processing service from the pricing service can enhance performance and reliability.”

3. Describe a time you optimized a piece of code. What was the outcome?

Optimization is key in trading systems where performance is critical.

How to Answer

Provide a specific example, detailing the initial performance issues, the steps you took to optimize the code, and the results.

Example

“I worked on a data processing module that was taking too long to execute. By analyzing the algorithm, I identified redundant calculations and implemented caching. This reduced the execution time by 40%, significantly improving the overall system performance.”

4. How do you ensure the quality of your code?

Quality assurance is vital in a trading environment.

How to Answer

Discuss your approach to testing, code reviews, and adherence to coding standards.

Example

“I follow a strict testing protocol that includes unit tests and integration tests. Additionally, I participate in code reviews to ensure adherence to best practices and to catch potential issues early in the development process.”

5. What is your understanding of data structures and algorithms, and how do they apply to trading systems?

A solid grasp of data structures and algorithms is essential for efficient trading systems.

How to Answer

Explain the importance of choosing the right data structures for specific tasks and how algorithms can optimize performance.

Example

“Efficient data structures like heaps and hash tables are crucial for implementing fast order matching systems. For example, using a priority queue can help manage orders based on their priority, ensuring that high-priority trades are executed first.”

Behavioral Questions

1. Why do you want to work at Optiver?

Understanding your motivation for joining the company is important.

How to Answer

Express your interest in the company’s mission, culture, and the challenges of the trading industry.

Example

“I admire Optiver’s commitment to improving market efficiency and transparency. The opportunity to work in a tech-driven environment where I can contribute to real-time trading systems excites me, as I thrive on solving complex problems.”

2. Tell me about a time you faced a significant challenge in a project. How did you handle it?

This question assesses your problem-solving skills and resilience.

How to Answer

Describe the challenge, your approach to resolving it, and the outcome.

Example

“During a project, we encountered a critical bug just before a major release. I organized a team meeting to brainstorm solutions, and we quickly identified the root cause. By reallocating resources and prioritizing the fix, we managed to resolve the issue and meet our deadline.”

3. How do you approach collaboration with traders and other engineers?

Collaboration is key in a trading environment.

How to Answer

Discuss your communication style and how you ensure alignment with team members.

Example

“I believe in maintaining open lines of communication with traders to understand their needs. I regularly schedule check-ins to gather feedback on our systems, which helps me align my engineering efforts with their trading strategies.”

4. Describe a situation where you had to learn a new technology quickly. How did you approach it?

Adaptability is crucial in a fast-paced environment.

How to Answer

Share your learning strategy and how you applied the new technology.

Example

“When I needed to learn a new data visualization library for a project, I dedicated time to online courses and hands-on practice. I built a prototype to visualize trading data, which helped me grasp the library’s capabilities quickly.”

5. What are your strengths and weaknesses as a software engineer?

Self-awareness is important for personal and professional growth.

How to Answer

Identify a strength that aligns with the role and a weakness you are actively working to improve.

Example

“One of my strengths is my attention to detail, which helps me catch bugs early in the development process. However, I sometimes struggle with delegating tasks. I’m working on this by actively seeking feedback from my team and trusting them with responsibilities.”

Here are some tips to help you excel in your interview.

Understand the Interview Process

The interview process at Optiver is multi-faceted, typically involving an online assessment, technical interviews, and behavioral interviews. Familiarize yourself with each stage, as candidates have reported a rigorous evaluation of both technical skills and cultural fit. Prepare for a coding challenge that may include algorithmic problems and system design questions, as well as behavioral questions that assess your motivations and problem-solving abilities.

Tailor Your Resume

Ensure your resume aligns with the specific requirements of the Software Engineer role. Highlight relevant experiences, particularly those that demonstrate your ability to lead projects, collaborate with cross-functional teams, and solve complex problems. Be prepared to discuss your resume in detail during the interview, as interviewers may ask about specific projects or technologies you've worked with.

Master the Technical Skills

Optiver values strong engineering instincts and a deep understanding of computer science fundamentals. Brush up on your knowledge of C++, Python, and Linux, as these are preferred languages for the role. Practice coding problems on platforms like LeetCode or HackerRank, focusing on data structures, algorithms, and system design. Candidates have noted that the technical questions can be challenging, so ensure you are comfortable with both theoretical concepts and practical applications.

Prepare for Behavioral Questions

Behavioral interviews at Optiver are taken seriously, so prepare to discuss your past experiences in detail. Expect questions about your motivations for wanting to work at Optiver, how you handle challenges, and your approach to teamwork. Use the STAR (Situation, Task, Action, Result) method to structure your responses, providing clear examples that showcase your problem-solving skills and ability to work under pressure.

Show Your Passion for Trading and Technology

Optiver is a tech-driven trading firm, and they seek candidates who are genuinely interested in both technology and the financial markets. Be prepared to discuss your understanding of trading concepts, market making, and how technology plays a role in these areas. Demonstrating a passion for the industry will help you stand out as a candidate who is not only technically proficient but also aligned with the company's mission.

Ask Insightful Questions

During your interviews, take the opportunity to ask thoughtful questions about the company culture, team dynamics, and the specific challenges the engineering team faces. This not only shows your interest in the role but also helps you assess if Optiver is the right fit for you. Candidates have noted that asking good questions can leave a positive impression on interviewers.

Embrace the Company Culture

Optiver prides itself on a collaborative and inclusive environment. Be yourself and let your personality shine through during the interview. Candidates have reported that the interviewers are friendly and approachable, so don’t hesitate to engage in a genuine conversation. Show that you are a team player who values collaboration and continuous improvement.

Follow Up

After your interviews, consider sending a thank-you email to express your appreciation for the opportunity to interview. This is a chance to reiterate your interest in the position and reflect on any key points discussed during the interview. A thoughtful follow-up can help keep you top of mind as the hiring team makes their decisions.

By preparing thoroughly and demonstrating your technical skills, passion for the industry, and cultural fit, you can position yourself as a strong candidate for the Software Engineer role at Optiver. Good luck!

The interview process for a Software Engineer at Optiver is structured to assess both technical skills and cultural fit within the organization. It typically consists of several stages, each designed to evaluate different aspects of a candidate's qualifications and alignment with Optiver's values.

1. Application Submission

Candidates begin by submitting their resume and cover letter. The application is reviewed to ensure that the candidate's background aligns with the requirements of the role. This initial step is crucial as it sets the stage for the subsequent assessments.

2. Online Assessment

Following a successful application review, candidates are invited to complete an online assessment. This assessment usually consists of coding challenges that test problem-solving abilities and technical skills, often using platforms like HackerRank. Candidates are typically given a set time frame to complete the assessment, which may include multiple questions of varying difficulty levels.

3. Recruiter Phone Interview

After passing the online assessment, candidates will have a phone interview with a recruiter. This conversation focuses on the candidate's background, motivations for applying to Optiver, and general fit for the company culture. It’s an opportunity for candidates to express their interest in the role and ask questions about the company.

4. Technical Interview

Candidates who perform well in the recruiter interview will proceed to a technical interview. This round often involves coding exercises and algorithmic questions, where candidates may be asked to solve problems in real-time while explaining their thought process. Interviewers assess not only the correctness of the solutions but also the candidate's approach to problem-solving and coding style.

5. Onsite or Virtual Interview

The final stage typically includes an onsite or virtual interview, which may consist of multiple rounds. Candidates can expect a mix of technical interviews, system design discussions, and behavioral interviews. This stage is designed to evaluate the candidate's ability to collaborate with traders and engineers, as well as their understanding of trading systems and infrastructure. Candidates may also be asked to present their solutions from the online assessment and discuss their design choices.

Throughout the interview process, candidates are encouraged to demonstrate their engineering instincts, problem-solving skills, and ability to work in a fast-paced, tech-driven environment.

As you prepare for your interview, consider the types of questions that may arise in each of these stages.

Here are the questions that are commonly asked in a Software Engineer interview at Optiver.

1. Tell me, what motivated you to work here at Optiver?

This question aims to understand your motivations, values, and alignment with Optiver’s culture and values. It helps the interviewer assess if you have done research on the software engineer role at the company.

How to Answer

While answering, be authentic and highlight particular aspects of Optiver that resonate with you. Also, mention your interest in the company’s industry reputation, its innovative and technology-driven environment, or any values and practices that align with your own.

Example

“I am motivated to work at Optiver because of its renowned reputation as a leading technology-driven trading firm. I am drawn to the challenging and dynamic nature of the work here, and the emphasis on innovation aligns perfectly with my passion for staying at the forefront of technology. Furthermore, Optiver’s commitment to fostering a collaborative and high-performance culture resonates with my own values. I am eager to contribute my skills in such an environment, driving technological advancements and contributing to the success of the team.

2. Tell me about a time when you handled a situation where your team member had a different point of view about doing a project.

The interviewer can ask this to test your interpersonal skills and ability to navigate collaborative work environments, which are essential qualities needed for the role of a software engineer at Optiver.

How to Answer

When answering this question, emphasize your communication and collaboration skills. Describe how you actively listen and understand your team members’ perspectives to work towards a consensus. Highlight your previous experience in this area to illustrate your approach.

Example

“In a previous project, a team member and I had different opinions on the project architecture. To address this, I initiated a meeting to openly discuss our viewpoints, focusing on understanding each other’s concerns. Through collaborative brainstorming, we found a middle ground that incorporated the strengths of both approaches. This led to a more effective solution and strengthened our working relationship. I believe fostering open communication and valuing diverse perspectives is essential for delivering successful projects in a team environment.”

3. Describe some ideas and initiatives you’ve led in the past. What was the outcome?

This question tests your capacity for innovation and leadership and the impact of your initiatives on past projects. Optiver seeks software engineers who not only excel in technical proficiency but can also drive and contribute to meaningful improvements in software development processes.

How to Answer

When answering, showcase projects where you initiated and led innovative ideas in software development in the past. Discuss the challenges you faced, the strategic actions you took, and the outcomes achieved.

Example

“In my previous role, recognizing a constraint in our deployment process, I proposed and implemented a containerization strategy using Docker. This initiative significantly reduced deployment times, enhancing our overall development lifecycle efficiency by 40%. It not only streamlined the release process but also led to improved collaboration among development and operations teams. This initiative showcased my proactive approach to addressing challenges and resulted in a more agile and efficient software development environment.”

4. Do you prefer to work with others or alone?

Optiver values both individual expertise and effective teamwork. This question is intended to test how well you can adapt to different work scenarios, collaborate with a team, and contribute effectively to various environments as a software engineer.

How to Answer

While answering, discuss your ability to work effectively in both team and independent settings. Discuss experiences where you successfully contributed to team projects and instances where you excelled while working on individual tasks.

Example

“I can work in both collaborative and independent work settings, which I believe aligns well with the dynamic environment at Optiver. In team projects, I bring strong collaboration and communication skills, fostering an environment where diverse perspectives lead to innovative solutions. Simultaneously, when working independently, I leverage my self-motivation and focus to deliver high-quality results. This adaptability has been evident in my past experiences, ensuring I can contribute effectively to both individual and team-oriented projects at Optiver.”

5. Tell me about a time when you had to adapt to a change in project. How did you handle it?

Assessing your adaptability, problem-solving skills, and ability to navigate changes in project requirements is a crucial aspect of being a software engineer at Optiver.

How to Answer

Provide a specific example from your experience where you faced a change in project requirements. Highlight the steps you took to adapt, including communication with team members, reassessment of project goals, and any other modifications you made to ensure successful project completion.

Example

“In my previous role, we faced a sudden change in project requirements due to shifting business priorities. To handle this, I initiated a team meeting to discuss the changes needed. I facilitated open communication, ensuring everyone understood the updated objectives. We collectively reassessed our approach, reprioritized tasks, and adjusted the project timeline accordingly. By maintaining transparency and a collaborative spirit, we successfully adapted to the changes, delivering a product that met the revised requirements on time.”

6. How would you handle the implementation of fractional shares in a financial trading system, considering both technical and business implications?

This question is asked to assess your understanding of the technical challenges and business considerations involved in implementing fractional shares, a key aspect of being a software engineer at Optiver.

How to Answer

To answer this question, discuss the technical aspects of implementing fractional shares, such as precision in calculations, data storage, and adjustments to trading algorithms to accommodate fractional quantities. Highlight the business implications and address how you would handle potential challenges.

Example

“To implement fractional shares, I’d ensure precision in calculations, adapt data storage to accommodate fractional quantities, and modify trading algorithms to seamlessly handle fractional share transactions. This will ensure accuracy and consistency in trade executions. On the business side, I’ll introduce fractional shares that can enhance accessibility for a broader range of investors, potentially increasing trading volumes. To address potential challenges, I’ll implement error-handling mechanisms. This will include addressing precision errors, validating calculations, and ensuring that dividend distributions are accurately proportioned.”

7. What is the difference between interface-oriented, object-oriented, and aspect-oriented programming?

This question aims to assess your understanding of different programming paradigms. At Optiver, software engineers need to design and implement complex trading systems, hence understanding various programming paradigms is crucial.

How to Answer

To answer this question, start by providing concise definitions for each programming paradigm, emphasizing the key differences between these paradigms.

Example

“In object-oriented programming, the primary focus is on encapsulating behavior and data into objects. This promotes modularity and code reuse through concepts like classes, inheritance, and polymorphism.

Interface-oriented programming centers around defining contracts (interfaces) that specify a set of methods without prescribing the implementation. This enables different classes to implement the same interface while providing their own unique implementations.

Aspect-oriented programming introduces the concept of aspects that separate cross-cutting concerns, such as logging, security, or error handling, from the core business logic. AOP provides a way to modularize and manage these concerns independently.”

8. Write a Python code to find the minimum number in a list of integers. If the list is empty, the function should return ‘None’.

This question assesses your ability to write a fundamental Python function. It assesses your proficiency in handling edge cases, such as an empty list. It tests your understanding of basic list operations and conditional statements, which are key concepts needed for the Optiver Software Engineer role.

How to Answer

To answer this question, design a function that takes a list of integers as input and returns the minimum value. Also, include logic to handle the case when the list is empty.

Example

“I would create a Python function named ‘find_minimum’ that takes a list of integers as its parameter. Inside the function, I’ll initially check if the list is empty using ‘if not list.’ In case of an empty list, I would return ‘None’ as specified. For a non-empty list, I’ll use the built-in ‘min()’ function to find the minimum value. This function simplifies the process of finding the minimum without the need for explicit iteration.”

9. What is the difference between structure and arrays?

This question aims to test your understanding of data structures and is relevant for assessing your grasp of core programming concepts. Optiver seeks software engineers with a solid understanding of data structures for efficient algorithm implementation.

How to Answer

To answer this question, begin by providing clear definitions for both structures and arrays. Explain their basic characteristics and purposes. Emphasize the key differences and discuss common uses.

Example

“In programming, structures, and arrays are two distinct data structures with different purposes and characteristics. An array is a collection of elements of the same data type stored in contiguous memory locations. Elements in an array are accessed using an index. Arrays are particularly useful when dealing with a homogeneous set of data, like a series of numbers. A structure, on the other hand, is a composite data type that groups together variables of different data types under a single name. Each variable in the structure is referred to as a member or field. Structures can store a combination of different data types.”

10. Explain the differences between Z-tests and T-tests, and provide a practical scenario where you might choose to use one test over the other. How would you interpret the results?

This question is asked to evaluate your statistical knowledge, problem-solving ability, and communication skills in selecting and interpreting Z-tests and T-tests relevant to potential software engineering scenarios.

How to Answer

To answer this question, start by briefly explaining the fundamental differences between Z-tests and T-tests. Describe a scenario relevant to the software engineering context. Explain why, in the given scenario, you would choose one test over the other. Describe how you would interpret the results.

Example

“Z-tests are appropriate when dealing with a large sample size or when the population standard deviation is known, while T-tests are more suitable for smaller sample sizes or when the standard deviation is unknown. For example, in a software optimization project comparing the average performance of two algorithms, we might not have sufficient data initially to estimate the population standard deviation accurately. In such a scenario, a T-test would be more appropriate due to its efficiency with smaller sample sizes and its ability to work with estimated standard deviations. Interpreting the results involves examining the p-value. If the calculated p-value is below our chosen significance level, say 0.05, I would reject the null hypothesis.”

11. How can you detect a cycle in a linked list?

This question can be asked in an Optiver Software Engineer interview to evaluate your problem-solving skills, as well as your ability to work with data structures, which is crucial for developing efficient algorithms in algorithmic trading systems.

How to Answer

One common approach is to use two pointers, often referred to as the slow pointer and the fast pointer. You can also describe using Floyd’s Tortoise and Hare Algorithm This is an efficient algorithm for cycle detection in a linked list. If there’s a cycle, the slow and fast pointers will eventually meet. Use a hash set to store visited nodes. If you encounter a node that is already in the set, there is a cycle.

Example

“I would approach the problem using Floyd’s Tortoise and Hare Algorithm. I would start by initializing two pointers, the slow pointer and the fast pointer, both set to the head of the linked list. The slow pointer would move forward one step at a time, while the fast pointer would move two steps at a time.

While traversing the linked list, I would continuously check if the slow pointer and the fast pointer are pointing to the same node. If they ever meet, it indicates the presence of a cycle in the linked list. The algorithm is efficient and guarantees the detection of a cycle if it exists. It works well for both large and small linked lists. This approach has a time complexity of O(n), where n is the number of nodes in the linked list, and a space complexity of O(1), as it doesn’t require additional storage beyond the two pointers.”

12. Write a function to calculate the standard deviation of a list of numbers without using built-in functions like numpy.std(). Explain your approach.

This question is asked to test your understanding of statistical calculations, algorithmic implementation, and considerations for numerical stability. It also assesses your ability to build essential functions from scratch, which is crucial for the Software Engineer role.

How to Answer

To answer this question, begin by explaining the algorithm you plan to use, detailing the steps involved in calculating the standard deviation. Discuss the time and space complexity of your implementation. Also, address how your function will handle edge cases such as an empty list or a list with a single element.

Example

“To calculate the standard deviation without using built-in functions, I would start by checking for edge cases. If the list has fewer than two elements, it’s not possible to calculate the standard deviation, so I would return ‘None.’ Assuming the list has sufficient elements, I would then proceed to the calculation. Firstly, I’d find the mean by summing up all the numbers and dividing by the length of the list. Next, I’d calculate the squared differences from the mean for each number in the list. Afterward, I would compute the variance by summing up these squared differences and dividing by the length of the list. Finally, I’d take the square root of the variance to obtain the standard deviation.”

def calculate_standard_deviation(numbers):
    if len(numbers) < 2:
        return None
    # Step 1: Calculate the mean
    mean = sum(numbers) / len(numbers)
    # Step 2: Calculate the squared differences from the mean
    squared_diff = [(x - mean) ** 2 for x in numbers]
    # Step 3: Calculate the variance
    variance = sum(squared_diff) / len(numbers)
    # Step 4: Calculate the standard deviation
    std_dev = variance ** 0.5
    return std_dev

13. Explain the process of dynamic memory allocation in C.

This question tests your understanding of memory management in C. Optiver, being involved in algorithmic trading, may seek candidates who can efficiently manage memory to optimize the performance of trading systems.

How to Answer

Describe how dynamic memory is allocated on the heap using functions like ‘malloc ‘and ‘calloc’. Emphasize the need for manual memory management and the programmer’s responsibility to free allocated memory using ‘free‘ to avoid memory leaks.

Example

“For dynamic memory allocation in C, the heap is utilized. Functions like ‘malloc’ and ‘calloc’ allow us to allocate memory on the heap. Unlike the stack, memory on the heap must be manually managed by the programmer. Failing to free allocated memory can lead to memory leaks, where the program consumes more and more memory without releasing it. The ‘free’ function is used to release memory allocated on the heap.”

14. What are the key differences between Lasso and Ridge Regression? Provide a practical scenario where you might choose one over the other.

This question is asked to assess your understanding of regularization methods like Ridge and Lasso regression. It also evaluates your ability to make informed choices based on real-world scenarios.

How to Answer

To answer this question, start by defining Ridge and Lasso regression as regularization techniques used in machine learning. Highlight key differences and explain how both methods address multicollinearity. Provide a scenario where you might choose one over the other based on the characteristics of the dataset.

Example

“Ridge and Lasso regression are regularization techniques employed in machine learning to combat overfitting. They both introduce a penalty term to the cost function, encouraging the model to use fewer features and address multicollinearity. Ridge employs the L2 norm penalty, summing the squared values of coefficients, while Lasso uses the L1 norm penalty, summing the absolute values.

In a practical scenario, if I were dealing with a dataset containing highly correlated features, I might opt for Ridge regression. This is because Ridge tends to shrink coefficients toward zero without necessarily eliminating them, making it suitable when all features may be relevant. On the other hand, if I were interested in feature selection and wanted to enforce sparsity, I might choose Lasso, which has the capability to drive certain coefficients to exactly zero.”

15. How will you define MVC architecture?

This question tests your understanding of fundamental architectural patterns. At Optiver, where sophisticated trading systems are developed, candidates are evaluated on their ability to create well-structured and modular code.

How to Answer

Begin by defining the three main components of MVC: Model, View, and Controller. Explain their respective roles in the architecture.

Example

“MVC (Model-View-Controller) is an architectural pattern that divides software applications into three key components. The Model handles data and business logic, the View manages the user interface, and the Controller acts as an intermediary, handling user input and updating both the Model and View. This separation enhances code organization, scalability, and maintainability. For instance, in a web application, the Model deals with data storage, the View presents the UI, and the Controller manages user input. MVC provides code reusability, clear separation of concerns, and ease of maintenance.”

16. Given a database table of bank transactions containing columns id, transaction_value, and created_at, write an SQL query to retrieve the last transaction for each day. The output should include the ID of the transaction, datetime of the transaction, and the transaction amount, ordered by datetime.

This question assesses your SQL querying skills and ability to work with date and time data. It evaluates your understanding of grouping, ordering, and retrieving specific information from a database. Because at Optiver, precision and efficiency in handling financial data are crucial.

How to Answer

To answer this question, start by using the ‘GROUP BY’ clause to group transactions by the date part of the ‘created_at’ column. Then, utilize the ‘MAX’ function to find the maximum datetime for each date, effectively getting the last transaction for each day. After that, join the result with the original table on the composite key of date and maximum datetime. Finally, use the ‘ORDER BY’ clause to sort the final results by datetime.

Example

“To retrieve the last transaction for each day from the bank transactions table, I would first group the transactions by their respective dates using the ‘GROUP BY’ clause on the date part of the ‘created_at’ column. In a subquery, let’s call it t2, I would then use the ‘MAX’ function to find the maximum datetime for each date, effectively identifying the last transaction timestamp for each day.

Next, I’d perform a join between the original transactions table and t2 using a composite key involving the date and the maximum datetime. This would allow me to fetch the specific details of the last transaction for each day, including the transaction ID, datetime, and transaction amount.

To ensure the final output is ordered chronologically, I would use the ‘ORDER BY’ *clause on the original ‘created_at’ column.”

17. Write a function ‘rain_days(n)’ in Python to calculate the probability that it will rain on the nth day after today, considering the given probabilities based on whether it rained yesterday or today. Assume that today is day 0. Explain your approach concisely.

This question evaluates your ability to design a function based on a probability scenario, reflecting real-world decision-making under specific conditions. Quantitative analysis is crucial at Optiver, as it tests your mathematical and coding skills in modeling and calculating probabilities.

How to Answer

To answer this question, I will design a function ‘rain_days(n)’ that takes the day number ‘n’ as an input and calculates the probability of rain on that day. I will implement conditions based on the information provided regarding the probability of rain, whether it rained yesterday or today. Finally, I will return the calculated probability for the nth day.

Example

“If tasked with creating the ‘rain_days’ function, I would start by considering the conditions given in the problem statement. First, I’d handle the edge case where the input day number ‘n’ is negative, returning an error message like “Invalid input. Day number should be non-negative.”

For days 0 and 1 (representing today and tomorrow), the probability of rain is specified in the problem statement, so I would directly return 0.2 for these cases.

For subsequent days (n > 1), I would leverage the information that if it rained yesterday and today, the probability of rain is 20%, and if it rained only one of the days, the probability is 60%. Therefore, I would use a conditional statement to check if the day number is even or odd, setting the probability accordingly.”

18. You’re given two data frames. One contains information about addressed,s and the other contains relationships between various cities and states. Write a function complete_address to create a single data frame with complete addresses in the format of street, city, state, and zip code.

This question is asked to assess a candidate’s ability to manipulate and combine data frames, a common task in data processing and analysis that is relevant in financial settings at Optiver. The ability to merge and transform data efficiently is crucial for tasks like risk assessment and trend analysis.

How to Answer

To answer this question, start by understanding the structure and content of the two data frames. Identify the common key(s) that can be used for merging. After that, describe and perform any necessary data cleaning or preprocessing steps. Then, merge the two data frames using the appropriate keys to create a single data frame. Use the merged data frame to create a new column.

Example

“If given two data frames, one containing address information and the other detailing relationships between cities and states, I would approach this task systematically. First, I’d examine the structure of both data frames to identify common keys for merging, ensuring seamless integration.

After merging the data frames, I would create a new column in the unified data frame to hold the complete addresses. This involves combining information from the street, city, state, and zip code columns. I’d use string concatenation or formatting to achieve the desired address format. To handle potential edge cases, such as missing or inconsistent data, I’d implement conditional checks and data cleaning steps.”

19. Write a function, friendship_timeline, that takes two lists of dictionaries, friends_added and friends_removed, containing user_ids and created_at times. The function outputs pairs of friends with corresponding timestamps for friendship beginnings and endings.

This question tests your ability to work with data structures, manipulate lists of dictionaries, and generate meaningful outputs. In financial contexts like those at Optiver, understanding and manipulating data efficiently is crucial for various tasks, including analyzing patterns in market behaviors.

How to Answer

To answer this question, begin by describing the extraction of the relevant information from the given lists of dictionaries, focusing on user_ids and created_at timestamps. Then, combine the information from friends_added and friends_removed based on user_ids to create a unified dataset that includes both friendship beginnings and endings. Sort the combined dataset based on the created_at timestamps. At the end, generate the desired output format, listing pairs of friends along with the corresponding timestamps.

Example

“If given two lists of dictionaries representing friendship beginnings (friends_added) and endings (friends_removed), I would approach this task systematically. First, I’d extract the relevant information, specifically the user_ids and created_at timestamps, from both lists.

Next, I would combine the information from both lists based on user_ids, creating a unified dataset that includes both friendship beginnings and endings. Sorting this dataset based on the created_at timestamps would give me a chronological timeline of friendship events.

Finally, I would generate the desired output, listing pairs of friends along with the corresponding timestamps for both the beginning and end of their friendship.”

20. When a random integer between N and M is input as the max value for another random function with the same min value N, what’s the distribution and expected value?

This question tests your understanding of probability and random processes, which is relevant in the Software Engineer role at Optiver, involving algorithmic trading and financial modeling.

How to Answer

To answer this question, begin by understanding the described process. Then, consider how the two random functions interact and how this affects the distribution of samples. Then, identify key characteristics such as the range of possible values and the likelihood of different outcomes. Lastly, calculate the expected value of the resulting distribution.

Example

“I would start by recognizing the constraint on the second function’s output range—limited by the initial random value. I would reason that the resulting distribution is a mixture of uniform distributions, with each one corresponding to a different value of X. To calculate the expected value, denoted as E(Y), I would average the outcomes in the range [N, M], weighted by the probability of each X. The precise mathematical expression would depend on the distribution of X. If X is uniformly distributed between N and M, the calculation would involve integrating over this range. The resulting distribution would be a composite of uniform distributions, offering a concise yet insightful understanding of the expected values in this scenario.”

21. Given a table of user sessions, write a query to get the number of days between each user’s first session and last session for the year 2020.

This question would be asked in an Optiver Software Engineer interview to assess your ability to work with time-based data and write SQL queries that extract meaningful insights. The question tests your understanding of window functions, data manipulation, and filtering data within specific timeframes.

How to Answer

Here, we will take advantage of SQL’s nifty DATEDIFF function, which calculates the difference between two dates. We would measure the difference between the first and the last dates.

We will use the MIN function to find the date of our first user session and the MAX function to find the date of their last session. Since dates are organized chronologically, from first (or smallest) to last (or largest), finding the minimum and maximum values in our table will give us the dates of our users’ first and last sessions.

Example

“I would start by focusing on calculating the number of days between each user’s first and last session in 2020. I’d use SQL’s DATEDIFF function to measure the difference between these dates. The key here is to identify the first and last sessions using the MIN and MAX functions, which would give me the earliest and latest session dates for each user within that year. To ensure we’re only looking at 2020 data, I’d include a condition to filter the sessions by year. Finally, I’d group the results by user ID to get a separate calculation for each user.”

22. Given an array of unsorted random numbers denoted nums, write a function find_iqr to find the interquartile distance.

This question would be asked to assess your ability to implement statistical concepts in code and work with arrays or lists effectively. It tests your problem-solving skills, specifically in handling sorting algorithms, calculating percentiles, and understanding the importance of statistical measures like the interquartile range (IQR) in analyzing data distribution.

How to Answer

To find the interquartile distance of a data set, we find the difference between the first quartile Q1 and the third quartile Q3. Q1 is the median of the lower half of the data, while Q3 is the median of the upper half of the data.

Example

“To solve this problem, I would start by sorting the array since we need an ordered data set to find the quartiles. Then, I’d split the array into two halves, representing the lower and upper halves of the data. From there, I would calculate the median of each half—these are our first and third quartiles, Q1 and Q3. The interquartile distance is simply the difference between Q3 and Q1.”

Now that you know the questions asked at the Optiver Software Engineer interview, here are some tips to ace the interview.

Understand the Tech Landscape

First, familiarize yourself with Optiver’s tech stack and recent technical advancements. Visit their website and gather as much information as possible about the position you’re applying for. Doing so will help you align your skills and tailor your resume accordingly.

Practice for the Optiver HackerRank Test

To strategically prepare for the Optiver HackerRank test, practice coding problems and make sure you cover a wide range of topics, programming languages, and data structures.

Explore our Learning Path feature for in-depth insights into coding challenges and further practice opportunities. Our Takehomes is an excellent resource for practicing and revising core concepts.

Showcase Problem-Solving Skills

While approaching a technical challenge in an interview, break down your solution into clear and simple steps. Showcase how you can simplify complex problems and communicate your thoughts effectively.

You can also check out our Challenges, where you can practice and test out your problem-solving abilities.

Communicate Effectively

In the technical interview, make sure to share your thoughts and communicate effectively while solving problems openly. Don’t hesitate to ask clarifying questions to ensure mutual understanding, which showcases your communication skills.

Enhance these skills and build confidence by practicing with our Mock Interviews. Take advantage of our Coaching feature as well for expert guidance to excel in your interview.

Practice Data Structures

Dedicate focused time to practicing various data structures, such as arrays, linked lists, stacks, and queues. Strengthen your problem-solving skills by solving coding challenges that involve these structures.

To gain access to a comprehensive set of questions and challenges related to data structures, practice using our Interview Questions. This resource is tailored for preparing you for your Software Engineer Interview at Optiver.

Here are some common questions frequently asked by candidates applying for the Software Engineer role at Optiver.

What is the average salary for a Software Engineer role at Optiver?

The average base salary for a Software Engineer at Optiver is $120,719. Adjusting the average for more recent salary data points, the average recency-weighted base salary is $119,546.

If you want to read more about software engineer salaries, head over to our main software engineer salary guide.

Are there job postings Optiver’s for Software Engineer positions at Interview Query?

No, there are no current job postings specifically for Optiver’s Software Engineer position on our platform. However, we encourage you to explore our Job Board, where you can discover opportunities from a variety of other companies in the tech industry.

As a Software Engineer, which other companies can I apply to?

You can apply to companies like Google, Microsoft, and Amazon, as well as innovative startups and fast-growing companies. Make sure to review our Company Interview Guides, which offer customized advice for different positions within various organizations to assist you in preparing for your upcoming interview.

At Interview Query, we aim to assist you in securing a Software Engineer position at Optiver.

For a comprehensive understanding of the company, we recommend exploring our main Optiver Interview Guide. This guide not only covers the Software Engineer role but also provides insights into Optiver’s Data Analyst and Scientist positions.

Using the information in our guides, improving your technical skills, and tackling problem-solving challenges head-on will prepare you for your Software Engineer interview at Optiver.

We hope this has been helpful in your preparation, and we wish you the best of luck.