Deliveroo

Senior Software Engineer

Software EngineerL5Hard

The Senior Software Engineer (L5) interview at Deliveroo is a comprehensive process designed to assess a candidate's technical expertise, problem-solving abilities, system design skills, and cultural fit within the company. It typically involves multiple rounds, including HR screening, technical interviews focusing on data structures and algorithms, a system design interview, and a final managerial or behavioral interview. The goal is to identify engineers who can independently tackle complex problems, mentor junior engineers, and contribute to the architectural direction of our products.

Rounds

4

Timeline

~14 days

Experience

5 - 10 yrs

Salary Range

US$120000 - US$150000

Total Duration

180 min

Overall Evaluation Criteria

Technical Skills (DSA & Coding)

Problem-solving skills
Algorithmic thinking
Data structure knowledge
Code quality and efficiency

System Design

System design principles
Scalability and reliability considerations
Trade-off analysis
Understanding of distributed systems

Behavioral and Cultural Fit

Communication skills
Teamwork and collaboration
Leadership potential
Adaptability and learning agility
Alignment with Deliveroo's values

Preparation Tips

1Review fundamental data structures and algorithms (arrays, linked lists, trees, graphs, hash maps, sorting, searching).
2Practice coding problems on platforms like LeetCode, HackerRank, or Coderbyte, focusing on medium to hard difficulty.
3Study system design concepts: load balancing, caching, databases, message queues, microservices, API design.
4Prepare to discuss your past projects in detail, focusing on your contributions, challenges, and learnings.
5Understand Deliveroo's business, technology stack, and engineering culture.
6Practice explaining your thought process clearly and concisely.
7Prepare questions to ask the interviewer about the role, team, and company.

Study Plan

1

Data Structures and Algorithms Fundamentals

Weeks 1-2: Data Structures & Basic Algorithms. Practice 2-3 problems/day. Big O.

Weeks 1-2: Focus on core data structures (Arrays, Linked Lists, Stacks, Queues, Hash Tables) and basic algorithms (Sorting, Searching, Recursion). Practice 2-3 problems per day. Understand time and space complexity (Big O notation).

2

Advanced Data Structures and Algorithms

Weeks 3-4: Advanced DSA. Practice 2-3 problems/day. DP, Greedy, Graphs.

Weeks 3-4: Dive into more advanced data structures (Trees, Tries, Graphs, Heaps) and algorithms (Dynamic Programming, Greedy Algorithms, Graph Traversal - BFS/DFS). Continue practicing 2-3 problems per day, focusing on applying these concepts.

3

System Design

Weeks 5-6: System Design. Study distributed systems, databases, caching, APIs. Practice case studies.

Weeks 5-6: Concentrate on System Design. Study common design patterns, distributed system concepts (CAP theorem, consistency models), database choices (SQL vs. NoSQL), caching strategies, message queues, and API design. Work through case studies and practice designing common systems (e.g., Twitter feed, URL shortener).

4

Behavioral and Cultural Fit

Week 7: Behavioral Prep. STAR method. Company values.

Week 7: Prepare for behavioral questions. Reflect on your past experiences using the STAR method (Situation, Task, Action, Result). Prepare examples related to teamwork, leadership, problem-solving, and handling conflict. Research Deliveroo's values and culture.

5

Mock Interviews and Review

Week 8: Mock Interviews. Timed practice. Feedback.

Week 8: Mock interviews. Practice coding and system design problems under timed conditions. Get feedback from peers or mentors. Review any weak areas identified during practice.

Commonly Asked Questions

Given a list of user activities, design a system to find the most active users in the last hour.
How would you design a real-time notification system for a food delivery app?
Explain the difference between process and thread. When would you use one over the other?
Describe a situation where you had to deal with a production issue. What was your approach?
How do you approach mentoring junior engineers?
What are the trade-offs of using a microservices architecture compared to a monolith?
Design a rate limiter for an API.
Tell me about a time you disagreed with a technical decision. How did you handle it?
How would you optimize a database query that is running slowly?
What are your thoughts on test-driven development (TDD)?

Location-Based Differences

London

Interview Focus

Deep understanding of distributed systems and microservices architecture.Experience with high-traffic, large-scale applications.Proficiency in specific programming languages and frameworks relevant to Deliveroo's tech stack (e.g., Java, Python, Go, Node.js).Ability to lead technical discussions and mentor junior engineers.

Common Questions

How would you design a URL shortening service like bit.ly?

Discuss a challenging technical problem you faced and how you solved it.

Explain the trade-offs between different database technologies (SQL vs. NoSQL).

How do you ensure the scalability and reliability of a distributed system?

Describe your experience with cloud platforms (AWS, GCP, Azure).

Tips

Familiarize yourself with Deliveroo's engineering blog and open-source contributions.
Be prepared to discuss your contributions to significant projects and their impact.
Understand the challenges of operating in a fast-paced, growth-oriented environment.
Highlight experience with A/B testing and data-driven decision-making.

Paris

Interview Focus

Strong grasp of software development best practices and design patterns.Experience with building and maintaining APIs.Ability to write efficient and well-tested code.Understanding of agile methodologies and CI/CD pipelines.

Common Questions

Design an API for a food delivery service.

How would you optimize the performance of a web application?

Discuss your approach to writing clean, maintainable, and testable code.

What are the principles of good API design?

How do you handle concurrency and parallelism in your applications?

Tips

Research Deliveroo's product offerings and business model.
Be ready to articulate your thought process clearly and concisely.
Showcase your ability to collaborate effectively within a team.
Prepare examples of how you've improved code quality or development processes.

Process Timeline

0
HR Screening Call30m
1
Technical Coding Round 145m
2
System Design Round60m
3
Behavioral and Managerial Round45m

Interview Rounds

4-step process with detailed breakdown for each round

0

HR Screening Call

Initial call with HR to discuss background, motivation, and expectations.

HR ScreeningEasy
30 minHR / Recruiter

This initial screening call with HR is to understand your background, motivations, and expectations. They will discuss your resume, career goals, and why you're interested in Deliveroo. It's also an opportunity for you to learn more about the company culture, the role, and the interview process. Be prepared to talk about your salary expectations and availability.

What Interviewers Look For

Genuine interest in Deliveroo.Clear understanding of the role's responsibilities.Good communication and interpersonal skills.Alignment with team and company culture.

Evaluation Criteria

Candidate's understanding of the role and company.
Alignment of candidate's expectations with the role.
Enthusiasm and engagement.
Cultural alignment.

Questions Asked

Can you walk me through your resume and highlight relevant experience?

HRResumeExperience

Why are you looking to leave your current role?

HRMotivation

What are your salary expectations for this role?

HRSalary

What do you know about Deliveroo?

HRCompany Knowledge

Preparation Tips

1Review your resume and be ready to discuss your experience.
2Research Deliveroo's mission, values, and recent news.
3Prepare questions about the role, team, and company culture.
4Be clear about your salary expectations.

Common Reasons for Rejection

Lack of clarity on career goals.
Poor fit with team dynamics.
Unrealistic salary expectations.
Failure to ask insightful questions.
1

Technical Coding Round 1

Solve 1-2 coding problems focusing on DSA and complexity.

Data Structures And Algorithms InterviewHard
45 minSoftware Engineer (L4/L5)

This round focuses on your core programming skills. You will be asked to solve 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 explain your approach. Expect questions that test your knowledge of arrays, strings, linked lists, trees, graphs, hash maps, sorting, searching, dynamic programming, and recursion.

What Interviewers Look For

Strong problem-solving skills.Proficiency in at least one programming language.Ability to translate requirements into working code.Understanding of fundamental data structures and algorithms.

Evaluation Criteria

Correctness of the solution
Efficiency of the solution (time and space complexity)
Clarity and organization of the code
Ability to handle edge cases and constraints
Communication of the thought process

Questions Asked

Given a binary tree, find the lowest common ancestor of two given nodes.

TreeRecursionBinary Tree

Implement a function to find the k-th largest element in an unsorted array.

ArraySortingHeapQuickSelect

Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.

StringStack

Preparation Tips

1Practice coding problems on platforms like LeetCode, HackerRank.
2Focus on understanding the underlying algorithms and data structures.
3Practice explaining your thought process out loud.
4Be prepared to discuss time and space complexity.

Common Reasons for Rejection

Poor communication of thought process.
Inability to identify edge cases.
Inefficient or incorrect algorithmic solutions.
Lack of understanding of time/space complexity.
2

System Design Round

Design a scalable, distributed system for a given problem.

System Design InterviewHard
60 minSenior Software Engineer / Engineering Manager

This round assesses your ability to design large-scale, distributed systems. You'll be given an open-ended problem (e.g., design a URL shortener, a social media feed, a ride-sharing service) and expected to design a system that meets specific requirements for scale, availability, and performance. You should be prepared to discuss various components, data models, APIs, trade-offs, and potential bottlenecks.

What Interviewers Look For

Experience designing complex, scalable systems.Understanding of distributed systems concepts.Ability to make reasoned technical decisions and justify trade-offs.Knowledge of various architectural patterns and technologies.

Evaluation Criteria

Clarity and completeness of the system design.
Scalability and performance considerations.
Reliability and fault tolerance.
Choice of appropriate technologies and trade-offs.
Ability to handle constraints and requirements.

Questions Asked

Design a system to count the number of views for millions of videos in real-time.

System DesignScalabilityReal-timeDatabases

Design a distributed cache system.

System DesignDistributed SystemsCachingScalability

Design the backend for a food delivery app like Deliveroo.

System DesignMicroservicesAPIsDatabases

Preparation Tips

1Study system design concepts: load balancing, caching, databases (SQL/NoSQL), message queues, microservices.
2Practice designing common systems.
3Be prepared to draw diagrams and explain your design choices.
4Consider scalability, availability, latency, and consistency.

Common Reasons for Rejection

Lack of understanding of distributed system principles.
Inability to design scalable and reliable systems.
Poor trade-off analysis.
Not considering failure scenarios or edge cases.
3

Behavioral and Managerial Round

Discuss past experiences, teamwork, leadership, and motivation.

Behavioral / Managerial InterviewMedium
45 minHiring Manager / Senior Team Member

This round focuses on your behavioral and cultural fit. You'll be asked questions about your past experiences, how you handle specific situations, your motivations, and your career goals. The interviewer wants to understand how you work with others, how you approach challenges, and whether you align with Deliveroo's values. Use the STAR method (Situation, Task, Action, Result) to structure your answers.

What Interviewers Look For

Evidence of collaboration and teamwork.Examples of leadership and initiative.Ability to handle challenging situations and learn from mistakes.Alignment with Deliveroo's mission and values.

Evaluation Criteria

Behavioral competencies (teamwork, leadership, problem-solving).
Cultural fit with Deliveroo.
Motivation and career aspirations.
Communication and interpersonal skills.

Questions Asked

Tell me about a time you had to work with a difficult colleague. How did you manage the situation?

BehavioralTeamworkConflict Resolution

Describe a project where you took a leadership role. What was the outcome?

BehavioralLeadershipProject Management

How do you stay updated with new technologies and industry trends?

BehavioralLearningAdaptability

Why are you interested in Deliveroo and this specific role?

BehavioralMotivationCompany Fit

Preparation Tips

1Prepare examples using the STAR method for common behavioral questions.
2Research Deliveroo's company culture and values.
3Be ready to discuss your strengths and weaknesses.
4Think about why you want to work at Deliveroo.

Common Reasons for Rejection

Poor communication or interpersonal skills.
Lack of alignment with company values.
Inability to articulate past experiences effectively.
Negative attitude or lack of enthusiasm.

Commonly Asked DSA Questions

Frequently asked coding questions at Deliveroo

View all
Remove Invalid ParenthesesHARDVertical Order Traversal of a Binary TreeHARDCount Number of Nice SubarraysMEDIUMSearch Suggestions SystemMEDIUMFind Words Containing CharacterEASY