Scale Engineer

Main Expert

Software Engineer22Expert

The Main Expert interview for a Software Engineer at Ozon, level 22, is a comprehensive assessment designed to evaluate deep technical expertise, problem-solving abilities, system design skills, and leadership potential. This interview is typically conducted by senior engineers or architects and focuses on complex challenges and strategic thinking.

Rounds·3

Timeline·~14d

Experience·8 - 15 yrs

Comp band·US$150000 - US$200000

Interview time·180 min

Evaluation

What they measure.

  • Depth of technical knowledge in core areas (algorithms, data structures, programming languages).
  • Proficiency in system design, architecture, and scalability.
  • Problem-solving skills and analytical thinking.
  • Ability to articulate complex technical concepts clearly.
  • Leadership potential and ability to mentor others.
  • Cultural fit and alignment with Ozon's values.

Preparation

How to prepare.

Tips

  1. Thoroughly review fundamental computer science concepts, including advanced algorithms and data structures.
  2. Practice system design problems, focusing on scalability, reliability, and trade-offs.
  3. Prepare to discuss your past projects in detail, highlighting your specific contributions and technical challenges.
  4. Understand Ozon's business and technology stack to tailor your answers.
  5. Reflect on leadership experiences and how you've influenced technical decisions.
  6. Be ready to discuss your approach to code quality, testing, and performance optimization.
  7. Prepare questions to ask the interviewer about the team, technology, and company culture.

Study plan

Fig · Study plan — 04 phases

01 / 04
01

Phase 01 of 04

Algorithms & Data Structures

Weeks 1-2: Advanced Algorithms & Data Structures (LeetCode Hard)

Weeks 1-2: Deep dive into advanced algorithms (e.g., graph algorithms, dynamic programming, string matching) and data structures (e.g., B-trees, skip lists, hash tables). Focus on time and space complexity analysis. Practice problems on platforms like LeetCode (Hard).

Questions

Commonly asked.

  • Design a system to handle real-time analytics for a large e-commerce platform.
  • How would you optimize the performance of a database query that is taking too long?
  • Describe a complex bug you encountered and how you debugged it.
  • What are the key principles of building a scalable and fault-tolerant system?
  • How do you approach mentoring junior engineers and fostering technical growth within a team?
  • Discuss a time you had a disagreement with a colleague on a technical approach and how you resolved it.
  • What are your thoughts on the trade-offs between monolithic and microservices architectures?
  • How would you design an API gateway for a set of microservices?
  • Explain the concept of eventual consistency and when it's appropriate to use.
  • What strategies do you employ to ensure high availability and disaster recovery for critical systems?

Locations

Regional differences.

Fig · Regions — 02 locations

01 / 02

Location

Moscow

Interview focus

Deep dive into specific technologies relevant to the local market and Ozon's tech stack.Emphasis on practical application of advanced algorithms and data structures.Understanding of local regulatory requirements and their impact on software development.

Common questions

  • Discuss a time you had to mentor junior engineers on a complex technical problem.
  • How would you design a distributed caching system for a high-traffic e-commerce platform?
  • Describe a challenging production issue you resolved and the impact it had.
  • What are your strategies for ensuring code quality and maintainability in large-scale projects?
  • How do you approach performance optimization for critical services?

Tips

  • Research Ozon's presence and specific projects in this region.
  • Be prepared to discuss your contributions to open-source projects if applicable.
  • Highlight experience with technologies commonly used by Ozon in this geographical area.

Rounds

Round-by-round.

Expand a step for evaluation criteria, sample questions, and prep notes.

DSA

Coding questions at Ozon.

Frequently reported on Ozon loops

View all at Ozon

Other guides

More at Ozon.