The Principal Software Engineer (L7) interview at Criteo is a rigorous process designed to assess deep technical expertise, leadership potential, and strategic thinking. Candidates are expected to demonstrate a strong command of software engineering principles, experience in designing and scaling complex systems, and the ability to mentor and guide other engineers. The interview process typically involves multiple rounds, including technical deep dives, system design, behavioral assessments, and a final discussion with senior leadership.
Rounds·4
Timeline·~14d
Experience·8 - 15 yrs
Comp band·US$170000 - US$220000
Interview time·225 min
Evaluation
Preparation
Tips
Study plan
Fig · Study plan — 04 phases
01 / 04Phase 01 of 04
Weeks 1-2: DSA fundamentals. LeetCode (Medium/Hard).
Weeks 1-2: Focus on core data structures and algorithms. Review common patterns and complexity analysis. Practice problems on platforms like LeetCode (Medium/Hard).
Phase 02 of 04
Weeks 3-4: System Design. Distributed systems, databases, caching.
Weeks 3-4: Dive into system design principles. Study topics like distributed systems, databases, caching, load balancing, and message queues. Read system design case studies.
Phase 03 of 04
Week 5: Behavioral preparation. STAR method.
Week 5: Prepare for behavioral questions using the STAR method (Situation, Task, Action, Result). Reflect on your career experiences, focusing on leadership, challenges, and successes.
Phase 04 of 04
Week 6: Criteo research. Ad-tech domain.
Week 6: Research Criteo's ad-tech domain, recent news, and technical challenges. Understand the ad ecosystem and Criteo's role within it. Prepare questions for the interviewers.
Questions
Locations
Fig · Regions — 03 locations
01 / 03Location
Interview focus
Common questions
Tips
Location
Interview focus
Common questions
Tips
Location
Interview focus
Common questions
Tips
Rounds
Expand a step for evaluation criteria, sample questions, and prep notes.
Technical Coding Interview · 60 min · Senior Software Engineer / Staff Engineer
This round focuses on your core programming skills and problem-solving abilities. You will be given one or two coding problems, typically involving data structures and algorithms. The interviewer will assess your ability to understand the problem, devise an efficient solution, write clean and correct code, and analyze its time and space complexity. Expect to discuss trade-offs and edge cases.
What they look for
Evaluation
Sample questions
Given a binary tree, find the lowest common ancestor of two given nodes.
Implement a function to find the k-th largest element in an unsorted array.
Design a data structure that supports insert, delete, search, and getRandom in O(1) average time.
Prep for this round
Common rejection reasons
System Design Interview · 60 min · Staff Engineer / Principal Engineer
This round evaluates your ability to design and architect large-scale distributed systems. You'll be presented with a high-level problem (e.g., design Twitter's feed, design a URL shortener) and expected to break it down, identify components, define APIs, and discuss scalability, reliability, and trade-offs. Focus on clarifying requirements, making reasonable assumptions, and justifying your design choices.
What they look for
Evaluation
Sample questions
Design a system to count unique visitors to a website in real-time.
Design a distributed rate limiter.
How would you design a notification system for millions of users?
Prep for this round
Common rejection reasons
Behavioral And Managerial Interview · 45 min · Hiring Manager / Engineering Manager
This round focuses on your past experiences, leadership potential, and how you work within a team. You'll be asked behavioral questions designed to elicit specific examples of your accomplishments, challenges faced, and how you handled them. Prepare to discuss your career goals, motivations, and why you're interested in Criteo and this specific role.
What they look for
Evaluation
Sample questions
Tell me about a time you had to lead a project from start to finish.
Describe a situation where you disagreed with a teammate or manager. How did you handle it?
How do you prioritize your work when faced with multiple competing tasks?
Prep for this round
Common rejection reasons
Senior Leadership / Executive Interview · 60 min · Director of Engineering / VP of Engineering
This final round is typically with a senior leader (Director or VP). It's a broader discussion about your career, your technical philosophy, your leadership style, and your vision for the future. They will assess your strategic thinking, your ability to influence at a high level, and your potential to contribute to Criteo's long-term technical success. Be prepared to discuss your biggest technical achievements and challenges.
What they look for
Evaluation
Sample questions
What is your vision for the future of ad-tech engineering?
Describe a time you had to make a significant technical decision with incomplete information.
How would you foster innovation within an engineering team?
Prep for this round
Common rejection reasons
DSA
Frequently reported on Criteo loops
Other guides
