This is where things went sideways for me.
Select a project that genuinely had significant complexity—such as multiple services, high scale, or ambiguous requirements—and narrate it as a story with a clear problem, your specific actions, and measurable outcomes. Focus on the technical trade-offs and system design decisions you made, not just what the team did.
Pro tip: Quantify the complexity and impact with concrete numbers (e.g., QPS, latency reduction, cost savings) and explicitly state the trade-offs you considered and why you chose your approach—this shows senior-level judgment.
Briefly describe the project's goal, why it was complex (e.g., scale, cross-team dependencies, legacy constraints), and your specific role. Use metrics to convey scale.
Detail 2-3 key challenges, such as consistency vs. availability, latency budgets, or data migration risks, and why they were hard to solve.
Describe the architecture or solution you proposed, including alternatives you considered and the trade-offs that led to your final choice.
Explain how you implemented the solution, overcame obstacles, and worked with other teams or stakeholders to deliver.
Quantify the outcome (e.g., performance improvement, cost reduction) and reflect on what you learned or would do differently.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.
Felt like a natural extension of the first question.
Start by clarifying the project's core requirements and scale, then outline a high-level architecture that addresses those needs. Focus on key components, data flow, and trade-offs, and explain how your design would evolve to handle Uber's scale and reliability demands.
Pro tip: Acknowledge the existing project's constraints and explain how a from-scratch design would differ, showing you understand both legacy and greenfield trade-offs. Emphasize simplicity and incremental scalability to demonstrate pragmatic engineering judgment.
Ask questions to understand functional and non-functional requirements, such as expected traffic, latency, consistency, and availability needs. This ensures your design targets the right problems.
Sketch the main components (e.g., services, databases, queues) and how they interact. Keep it abstract initially, focusing on data flow and boundaries.
Select 1-2 key areas (e.g., data storage, scaling, fault tolerance) and discuss design choices, technologies, and trade-offs in more detail.
Explain how the design handles growth, failures, and monitoring. Mention techniques like sharding, replication, caching, and load balancing.
Conclude with the main trade-offs made and how the design could evolve over time. Highlight any assumptions and potential improvements.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.
Use the STAR method to structure your answer, focusing on a specific conflict and your actions to resolve it. Emphasize empathy, data-driven decision making, and a positive outcome that benefited the team and the product. Keep the story concise and highlight what you learned.
Pro tip: Show that you can disagree without being disagreeable: acknowledge the other person's perspective and focus on shared goals. Mention how you followed up to ensure the resolution stuck, demonstrating long-term relationship management.
Briefly describe the project, your role, and the stakeholder/teammate involved. Keep it concise to focus on the conflict.
Clearly state the disagreement, such as differing technical approaches or priorities, without blaming the other person.
Detail how you addressed it: listened actively, sought to understand their perspective, and used data or user impact to find common ground.
Explain the outcome, including any compromise or decision made, and how it benefited the project or team.
Summarize what you learned and how you've applied it to prevent similar conflicts in the future.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.