# Software Engineer II **Role:** Software Engineer · **Level:** IC2 **Company:** [Reddit](https://scaleengineer.com/companies/reddit) **Difficulty:** Medium **Salary:** US$120000 - US$160000 **Experience:** 2 - 5 **Timeline:** ~14 days This interview process is designed to assess candidates for a Software Engineer II position at Reddit. It evaluates technical proficiency, problem-solving skills, system design capabilities, and cultural fit within the company. Canonical: https://scaleengineer.com/interviews/reddit/ic2-software-engineer --- ## Overall evaluation - Technical Skills - System Design - Behavioral & Cultural Fit ## Questions asked - Given a stream of user activity logs, how would you detect anomalies? - Design a system to recommend related subreddits to users. - Describe a time you disagreed with a technical decision and how you handled it. - How would you optimize the performance of a high-traffic API endpoint? - What are the trade-offs between SQL and NoSQL databases for a social media platform? - Tell me about a project you are particularly proud of. - How would you implement a real-time notification system for new comments on a post? ## Preparation tips ### lists - Review fundamental data structures and algorithms. - Practice system design problems, focusing on scalability and trade-offs. - Prepare examples for common behavioral questions using the STAR method. - Understand Reddit's products, mission, and recent developments. - Familiarize yourself with common technologies used at Reddit (e.g., Python, Go, React, AWS). ### studyPlan - {"title":"Data Structures & Algorithms","longDescription":"Weeks 1-2: Focus on core data structures (arrays, linked lists, trees, graphs, hash maps) and algorithms (sorting, searching, dynamic programming, graph traversal). Practice problems on platforms like LeetCode, HackerRank, and Cracking the Coding Interview.","shortDescription":"Weeks 1-2: DSA Fundamentals (Arrays, Lists, Trees, Graphs, Hash Maps, Sorting, Searching, DP, Graph Traversal)."} - {"title":"System Design","longDescription":"Weeks 3-4: Dive into system design concepts. Study topics like database design, caching, load balancing, message queues, microservices, and distributed systems. Practice designing common systems like Twitter feed, URL shortener, or a chat application.","shortDescription":"Weeks 3-4: System Design (Databases, Caching, Load Balancing, Message Queues, Microservices, Distributed Systems)."} - {"title":"Behavioral Preparation","longDescription":"Week 5: Prepare for behavioral questions. Reflect on past experiences related to teamwork, problem-solving, leadership, and conflict resolution. Use the STAR method (Situation, Task, Action, Result) to structure your answers.","shortDescription":"Week 5: Behavioral Prep (STAR Method, Teamwork, Problem-Solving, Leadership)."} - {"title":"Company & Role Research","longDescription":"Week 6: Research Reddit's tech stack, products, and company culture. Understand their business model and recent news. Prepare questions to ask the interviewer about the role, team, and company.","shortDescription":"Week 6: Company Research & Question Preparation (Reddit's Tech, Products, Culture)."} ## Location differences - {"location":"San Francisco Bay Area","differences":{"tips":["Research local Reddit communities and their specific interests.","Be prepared to discuss how your skills align with the local job market."],"interviewFocus":["Adaptability to local tech community trends","Understanding of regional user behavior"],"commonQuestions":["How would you design a URL shortener for Reddit?","Discuss a time you had to deal with a difficult stakeholder.","What are your thoughts on the current state of web development frameworks?"]}} - {"location":"Remote","differences":{"tips":["Highlight experience with large-scale data processing.","Be ready to discuss your contributions to open-source projects."],"interviewFocus":["Experience with distributed systems and scalability","Familiarity with cloud infrastructure (AWS, GCP)"],"commonQuestions":["How would you optimize a feed algorithm for a specific demographic?","Describe a challenging debugging scenario you encountered.","What are your favorite open-source projects and why?"]}} ## Round 1: Technical Coding Round 1 **Type:** Data Structures and Algorithms Interview · **Difficulty:** Medium · **Duration:** 45 min Coding challenge focusing on DSA. This round focuses on your fundamental computer science knowledge. You will be presented with coding problems that require you to apply data structures and algorithms to find efficient solutions. The interviewer will assess your ability to understand the problem, devise a strategy, write clean and working code, and analyze its time and space complexity. **Interviewers look for:** Clear thinking; Ability to break down complex problems; Clean and efficient code; Knowledge of common data structures and algorithms **Evaluation criteria:** Problem-solving approach; Code correctness; Efficiency of solution; Understanding of data structures **Common rejection reasons:** Inability to articulate thought process; Poor understanding of fundamental algorithms; Inefficient code ## Questions - Given an array of integers, find the contiguous subarray with the largest sum. - Implement a function to reverse a linked list. - Find the kth smallest element in an unsorted array. ## Preparation tips - Practice coding problems on platforms like LeetCode. - Understand the time and space complexity of your solutions. - Be able to explain your thought process clearly. - Review common data structures and algorithms. ## Round 2: System Design Round **Type:** System Design Interview · **Difficulty:** Hard · **Duration:** 60 min Design a scalable system. This round assesses your ability to design complex, scalable, and reliable systems. You will be given an open-ended problem, such as designing a social media feed or a URL shortener, and expected to discuss various components, data models, APIs, and potential bottlenecks. Emphasis is placed on your ability to reason about trade-offs and justify your design decisions. **Interviewers look for:** Ability to design scalable and robust systems; Understanding of distributed system concepts; Consideration of various trade-offs; Clear communication of design choices **Evaluation criteria:** System design principles; Scalability; Reliability; Trade-off analysis; API design **Common rejection reasons:** Lack of understanding of distributed systems; Inability to handle scale; Poor trade-off analysis ## Questions - Design a system to handle Reddit's front page. - How would you design a real-time analytics dashboard for user engagement? - Design a distributed rate limiter. ## Preparation tips - Study common system design patterns and architectures. - Practice designing systems like Twitter, Facebook News Feed, or a distributed cache. - Understand concepts like load balancing, caching, databases, and message queues. - Be prepared to discuss trade-offs for different design choices. ## Round 3: Behavioral & Manager Round **Type:** Behavioral Interview · **Difficulty:** Medium · **Duration:** 45 min Assessing behavioral and cultural fit. This interview focuses on your behavioral and cultural fit. The hiring manager will ask questions about your past experiences, how you handle challenges, work in teams, and your motivations. They are looking for evidence of collaboration, problem-solving, and alignment with Reddit's values. Be prepared to share specific examples using the STAR method. **Interviewers look for:** Effective communication; Collaboration potential; Alignment with Reddit's values; Self-awareness and reflection; Enthusiasm for the role and company **Evaluation criteria:** Communication skills; Teamwork; Problem-solving approach; Cultural fit; Past experiences **Common rejection reasons:** Poor communication skills; Lack of collaboration; Negative attitude; Mismatch with company values ## Questions - Tell me about a time you had to work with a difficult teammate. - Describe a challenging technical problem you faced and how you solved it. - Why are you interested in working at Reddit? ## Preparation tips - Prepare examples using the STAR method for common behavioral questions. - Research Reddit's company culture and values. - Think about your career goals and why you are interested in this role. - Prepare thoughtful questions to ask the interviewer.