Track: SDE-3 / Senior

Compass - SDE-3 / Senior Interview Briefing

Overview

Compass targets senior engineers with a focus on scalable system design and complex problem-solving. The interview process for SDE-3 candidates includes a mix of platform-based coding rounds, domain-specific challenges, and system design evaluations. Expect questions that test your ability to design and optimize systems for real-world applications, such as logistics or delivery integrations.

Round Breakdown & Questions

1. Technical Round (Karat Platform)

Format: Conducted on the Karat platform, this round assesses coding fluency under time constraints. Narrative: Candidates are expected to solve one or more problems fully or partially, demonstrating clean code and efficient algorithms. Key Observations:

• Time management is critical; candidates often struggle to complete the second question due to time constraints.
• Focus on writing readable, maintainable, and efficient code.

2. Coding Round (Dependency Resolution)

Format: Domain-specific coding challenge focused on dependency graphs and transitive closure. Narrative: Candidates are given an array of system dependencies and a query set to determine if the queries depend directly or transitively on the given dependencies.

Exact Question Asked:

Given a dependency array: {{1,2}, {2,3}, {4,5}} and a query array: {{1,3}, {3,4}, {5,4}}, return {true, false, false}.

Key Concepts Tested:

• Graph traversal (BFS/DFS) to determine transitive dependencies.
• Handling edge cases (e.g., cyclic dependencies, disconnected components).
• Optimizing for time and space complexity.

3. System Design Round (Drone Delivery Integration)

Format: Low-Level Design (LLD) and System Design round focused on scalability and integration. Narrative: Candidates are asked to design a system for Swiggy to support drone deliveries, emphasizing reuse of existing systems and addressing scalability challenges.

Key Focus Areas:

• Low-Level Design (LLD): Modularity, API design, and data flow for drone delivery integration.
• System Design: Scalability, fault tolerance, and real-time processing for high-throughput systems.
• Trade-offs: Balancing cost, latency, and reliability in a logistics-heavy application.

Follow-up Questions (Expected):

1. How would you handle failed deliveries or retry mechanisms?
2. How do you ensure real-time tracking of drones?
3. How would you design the billing system for drone deliveries?
4. What monitoring and alerting mechanisms would you implement?

Preparation Tips

1. Practice Dependency Graphs: Brush up on graph algorithms (BFS/DFS) and transitive closure problems.
2. System Design: Focus on designing scalable systems for logistics, e.g., delivery networks, payment gateways, or real-time tracking systems.
3. Low-Level Design: Be prepared to design APIs, data models, and interaction flows for specific use cases.
4. Karat Platform: Simulate coding under time constraints; practice explaining your thought process clearly.

Red Flags

• Incomplete or unoptimized solutions in coding rounds.
• Lack of clarity in trade-offs during system design discussions.
• Poor communication of assumptions or edge cases.