# Software Engineer **Role:** Software Engineer · **Level:** L1 **Company:** [Citadel](https://scaleengineer.com/companies/citadel) **Difficulty:** Medium **Salary:** US$75000 - US$95000 **Experience:** 0 - 2 **Timeline:** ~7 days This interview process is for a Software Engineer (L1) role at Citadel. It is designed to assess foundational technical skills, problem-solving abilities, and cultural fit. Canonical: https://scaleengineer.com/interviews/citadel/l1-software-engineer --- ## Overall evaluation - Technical Skills - Communication - Behavioral and Cultural Fit ## Questions asked - Write a function to reverse a linked list. - Explain the difference between a process and a thread. - What is Big O notation and why is it important? - Describe a time you had to debug a complex issue. - How would you design a URL shortener? - Tell me about a project you are proud of. - What are your strengths and weaknesses? ## Preparation tips ### lists - Review fundamental computer science concepts (data structures, algorithms, operating systems, databases). - Practice coding problems on platforms like LeetCode, HackerRank, or similar. - Understand object-oriented programming principles. - Prepare to discuss your past projects and technical experiences in detail. - Research Citadel's mission, values, and recent work. - Practice behavioral questions using the STAR method (Situation, Task, Action, Result). ### studyPlan - {"title":"Data Structures and Algorithms","longDescription":"Weeks 1-2: Focus on core data structures (arrays, linked lists, stacks, queues, trees, graphs, hash tables) and their common algorithms (sorting, searching, traversal). Practice implementing these from scratch and analyze their time and space complexity.","shortDescription":"Weeks 1-2: Data Structures & Algorithms fundamentals. Practice implementations and complexity analysis."} - {"title":"Algorithmic Techniques","longDescription":"Week 3: Deep dive into algorithmic techniques such as recursion, dynamic programming, greedy algorithms, and divide and conquer. Solve problems that require these approaches.","shortDescription":"Week 3: Algorithmic techniques (recursion, DP, greedy, divide & conquer). Solve related problems."} - {"title":"Core CS Concepts","longDescription":"Week 4: Brush up on object-oriented programming (OOP) concepts (encapsulation, inheritance, polymorphism, abstraction) and design patterns. Review basic operating system concepts and database fundamentals (SQL, relational databases).","shortDescription":"Week 4: OOP, Design Patterns, OS & Database basics."} - {"title":"Behavioral and Company Research","longDescription":"Week 5: Prepare for behavioral questions. Reflect on your past experiences, identify key projects, and structure your answers using the STAR method. Research Citadel's culture and values.","shortDescription":"Week 5: Behavioral preparation (STAR method) and company research."} ## Location differences - {"location":"New York","differences":{"tips":["Research Citadel's presence and projects in this specific region.","Be prepared to discuss your understanding of the local tech ecosystem.","Highlight any experience working in diverse or international teams."],"interviewFocus":["Adaptability to local work culture","Communication skills in the local language (if applicable)","Understanding of local market trends"],"commonQuestions":["Tell me about a challenging project you worked on.","How do you handle tight deadlines?","Describe a time you disagreed with a teammate."]}} - {"location":"Remote","differences":{"tips":["Emphasize your ability to work effectively in a remote or hybrid setting.","Showcase your experience with tools like Slack, Zoom, Jira, etc.","Be ready to discuss how you maintain productivity and communication remotely."],"interviewFocus":["Proficiency with remote collaboration tools","Self-management and time management skills","Understanding of distributed team dynamics"],"commonQuestions":["What are your thoughts on remote collaboration tools?","How do you stay motivated when working independently?","Describe your experience with agile methodologies."]}} ## Round 1: Technical Coding Round **Type:** Technical Interview (Coding) · **Difficulty:** Medium · **Duration:** 45 min Coding challenge focused on data structures and algorithms. This round focuses on your core technical abilities. You will be asked to solve coding problems, typically involving data structures and algorithms. The interviewer will assess your problem-solving approach, your ability to write correct and efficient code, and how well you can explain your thought process. **Interviewers look for:** Clear and logical thinking; Ability to write clean, efficient code; Understanding of time and space complexity; Effective communication of solutions **Evaluation criteria:** Problem-solving skills; Coding proficiency; Understanding of data structures and algorithms; Communication of approach **Common rejection reasons:** Inability to articulate thought process; Poor understanding of fundamental algorithms; Code with significant bugs or inefficiencies ## Questions - Given an array of integers, return indices of the two numbers such that they add up to a specific target. - Implement a queue using two stacks. - Find the kth smallest element in a binary search tree. ## Preparation tips - Practice coding problems extensively. - Be prepared to explain your code line by line. - Think out loud and communicate your strategy before coding. - Consider edge cases and test your code mentally. ## Round 2: Behavioral and Fit Round **Type:** Behavioral Interview · **Difficulty:** Easy · **Duration:** 30 min Assesses behavioral competencies and cultural fit. This round assesses your behavioral aspects and how you fit within the team and Citadel's culture. You'll be asked questions about your past experiences, how you handle specific situations, and your motivations. The STAR method is highly recommended for answering these questions. **Interviewers look for:** Evidence of teamwork and collaboration; Ability to handle challenges and learn from mistakes; Enthusiasm and passion for software development; Good communication and interpersonal skills **Evaluation criteria:** Behavioral competencies; Teamwork and collaboration skills; Problem-solving in past situations; Motivation and career goals **Common rejection reasons:** Lack of clarity in explaining past experiences; Inability to provide specific examples; Poor alignment with team values or company culture ## Questions - Tell me about a time you faced a difficult technical challenge and how you overcame it. - Describe a situation where you had to work with a difficult team member. How did you handle it? - Why are you interested in working at Citadel? ## Preparation tips - Prepare specific examples using the STAR method. - Reflect on your strengths, weaknesses, and career aspirations. - Understand Citadel's values and how you align with them. - Be ready to ask thoughtful questions about the role and team.