Scale Engineer

Software Engineer

Software EngineerSoftware Engineer IMedium

This interview process is designed to assess candidates for a Software Engineer I position at Duolingo. It evaluates technical skills, problem-solving abilities, cultural fit, and potential for growth within the company.

Rounds·3

Timeline·~7d

Experience·0 - 2 yrs

Comp band·US$85000 - US$110000

Interview time·150 min

Evaluation

What they measure.

  • Problem-solving approach
  • Code quality and efficiency
  • Understanding of data structures and algorithms
  • Ability to articulate technical concepts

Preparation

How to prepare.

Tips

  1. Review fundamental data structures and algorithms.
  2. Practice coding problems on platforms like LeetCode or HackerRank.
  3. Understand object-oriented programming principles.
  4. Brush up on your knowledge of system design concepts.
  5. Prepare to discuss your past projects and experiences using the STAR method (Situation, Task, Action, Result).
  6. Research Duolingo's products, mission, and values.
  7. Prepare questions to ask the interviewer about the role, team, and company culture.

Study plan

Fig · Study plan — 04 phases

01 / 04
01

Phase 01 of 04

Data Structures and Algorithms

Weeks 1-2: Data Structures & Algorithms fundamentals. Practice implementations and complexity analysis.

Weeks 1-2: Focus on core data structures (arrays, linked lists, trees, graphs, hash maps) and algorithms (sorting, searching, dynamic programming, recursion). Practice implementing these in your preferred language and analyze their time and space complexity.

Questions

Commonly asked.

  • Tell me about a challenging technical problem you faced and how you solved it.
  • How would you design a system to recommend new lessons to users based on their learning progress?
  • What are your favorite programming languages and why?
  • Describe a time you disagreed with a teammate and how you resolved it.
  • How do you stay up-to-date with new technologies and trends in software engineering?
  • Write a function to reverse a linked list.
  • Explain the concept of recursion with an example.
  • What are the differences between a process and a thread?
  • How would you approach debugging a performance issue in a web application?
  • Why are you interested in working at Duolingo?

Locations

Regional differences.

Fig · Regions — 02 locations

01 / 02

Location

Global

Interview focus

Understanding of core software engineering principles.Ability to write clean, maintainable, and efficient code.Problem-solving and debugging skills.Collaboration and communication skills.

Common questions

  • How would you approach building a feature to track user progress in a new language course?
  • Describe a time you had to debug a complex issue in a production environment.
  • What are your thoughts on code reviews and how do you provide constructive feedback?

Tips

  • Familiarize yourself with Duolingo's product and mission.
  • Be prepared to discuss your past projects and contributions in detail.
  • Practice explaining technical concepts clearly and concisely.

Rounds

Round-by-round.

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

DSA

Coding questions at Duolingo.

Frequently reported on Duolingo loops

View all at Duolingo

Other guides

More at Duolingo.