Duo Security, a part of Cisco, is recognized for its leading secure access solutions, addressing security concerns for a broad spectrum of businesses globally. With its mission focused on democratizing security and ensuring access safety, Duo Security stands tall in the cybersecurity domain.

Joining Duo Security as a Data Engineer means delving into a role critical to the company's operational effectiveness. This position demands strong technical acumen, including skills in data architecture, ETL processes, database management, and big data technologies. As a Data Engineer, you will collaborate with cross-functional teams to design and implement robust, scalable data solutions that drive informed decision-making and enhance security measures.

If you are contemplating a Data Engineer position at Duo Security, this guide on Interview Query provides you with a comprehensive look at the interview process, commonly asked questions, and valuable insights to help you succeed. Let’s begin the journey to securing your position at Duo!

Submitting Your Application

The first step is to submit a compelling application that reflects your technical skills and interest in joining Duo Security as a Data Engineer. Whether you were contacted by a Duo Security recruiter or have taken the initiative yourself, carefully review the job description and tailor your CV according to the prerequisites.

Tailoring your CV may include identifying specific keywords that the hiring manager might use to filter resumes and crafting a targeted cover letter. Furthermore, don’t forget to highlight relevant skills and mention your work experiences.

Recruiter/Hiring Manager Call Screening

If your CV happens to be among the shortlisted few, a recruiter from the Duo Security Talent Acquisition Team will make contact and verify key details like your experiences and skill level. Behavioral questions may also be a part of the screening process.

In some cases, the Duo Security Data Engineer hiring manager stays present during the screening round to answer your queries about the role and the company itself. They may also indulge in surface-level technical and behavioral discussions.

The whole recruiter call should take about 30 minutes.

Technical Virtual Interview

Successfully navigating the recruiter round will present you with an invitation for the technical screening round. Technical screening for the Duo Security Data Engineer role usually is conducted through virtual means, including video conference and screen sharing. Questions in this 1-hour long interview stage may revolve around Duo Security’s data systems, ETL pipelines, and SQL queries.

In the case of data engineer roles, take-home assignments regarding data processing, analytics, and data pipeline creation may be incorporated. Apart from these, your proficiency against data storage solutions, cloud services, and programming fundamentals may also be assessed during the round.

Depending on the seniority of the position, case studies and similar real-scenario problems may also be assigned.

Onsite Interview Rounds

Followed by a second recruiter call outlining the next stage, you’ll be invited to attend the onsite interview loop. Multiple interview rounds, varying with the role, will be conducted during your day at the Duo Security office. Your technical prowess, including programming and data engineering capabilities, will be evaluated against the finalized candidates throughout these interviews.

If you were assigned take-home exercises, a presentation round may also await you during the onsite interview for the Data Engineer role at Duo Security.

Quick Tips For Duo Security Data Engineer Interviews

• Understand Duo Security's Products: Study Duo Security’s suite of security products and understand how data engineering contributes to these products. Be prepared to discuss how you would improve or optimize data systems for their use cases.
• Be Technical and Analytical: Duo Security’s data engineering interviews assess how well you can handle large-scale data systems and provide business-driving insights with data engineering solutions. Brush up on your knowledge of databases, cloud services, and data processing.
• Showcase Collaboration Skills: Duo Security values a collaborative culture that focuses on security and innovation. Practice responding to behavioral questions with answers that highlight your teamwork, problem-solving abilities, and alignment with the company's mission.

Click here to sign up

Typically, interviews at Duo Security vary by role and team, but commonly Data Engineer interviews follow a fairly standardized process across these question topics.

• Create a function is_subsequence to determine if one string is a subsequence of another. Given two strings, string1 and string2, write a function is_subsequence to find out if string1 is a subsequence of string2.

• Implement a SinglyLinkedList class with methods to manipulate the list. Create a class SinglyLinkedList with methods to add and remove elements from the head and tail, check for item existence, access elements by index, and get the list's length.

• Write a function swap_node to swap nodes at given positions in a singly linked list. Given the head of a singly linked list and two positions x and y, write a function swap_node to swap the nodes at these positions using pointer manipulation, not by swapping values.

• Would a logistic model still be valid if a key variable had a data quality issue? Assume a logistic model is heavily weighted on one variable with sample data like 50.00, 100.00, 40.00, etc. If there was a data quality issue where some values lost their decimal points (e.g., 100.00 turned into 10000), would the model still be valid? Why or why not? How would you fix the model?

• How would you design a system to minimize missing or wrong orders on DoorDash? As a data scientist at DoorDash, you need to build a machine learning system to minimize missing or wrong orders placed on the app. How would you go about designing this system?

• What is the relationship between PCA and K-means clustering? Explain the relationship between Principal Component Analysis (PCA) and K-means clustering.

• How would you classify posts by topic on a large-scale social media website? You work at a social media website and want to build a system to automatically detect the topic of new posts. Given that several thousand posts are created every hour, how would you create a machine learning model to classify posts by topic at this scale?

• What are kernel methods in machine learning and their requirements?

• What are kernel methods in machine learning?
• What are the requirements for a matrix to represent a kernel?
• What happens if we run a support vector machine model using a kernel that does not satisfy these requirements?

If you want more insights about the company, check out our main Duo Security Interview Guide, where we have covered many interview questions that could be asked. We've also created interview guides for other roles, such as software engineer and data analyst, where you can learn more about Duo Security's interview process for different positions.

At Interview Query, we empower you to unlock your interview prowess with a comprehensive toolkit, equipping you with the knowledge, confidence, and strategic guidance to conquer every Duo Security Data Engineer interview question and challenge.

You can check out all our company interview guides for better preparation, and if you have any questions, don’t hesitate to reach out to us.

Good luck with your interview!