Architect a real-time Search Engine
Last updated: November 26, 2025
Quick Overview
Design a real-time search system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.
Redfin
November 26, 202512
13
2,470 solved
Design a real-time search system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.
This is a common system design question asked during System Design Round at Redfin. The interviewer expects you to demonstrate your ability to design large-scale distributed systems, make well-reasoned trade-offs, and communicate your thought process clearly. Redfin values engineers who can think about scalability from day one.
What the Interviewer Expects
- Drive the design discussion proactively with minimal interviewer guidance
- Perform detailed capacity estimation and use it to inform design decisions
- Design for global scale with multi-region deployment and data consistency
- Deep dive into 2-3 critical components with implementation-level detail
- Address complex trade-offs: CAP theorem, eventual consistency, conflict resolution
- Discuss operational excellence: deployment strategy, chaos engineering, SLOs/SLIs
- Propose a phased rollout plan from MVP to full-scale system
Key Topics to Cover
How to Approach This
- Start by clarifying functional and non-functional requirements with the interviewer.
- Estimate the scale: QPS, storage, bandwidth. This drives your design decisions.
- Draw a high-level architecture first, then deep dive into 1-2 critical components.
- Discuss trade-offs explicitly (e.g., consistency vs availability, SQL vs NoSQL).
- Address failure scenarios, monitoring, and how the system handles 10x traffic spikes.
Possible Follow-up Questions
- How would you migrate from a monolithic to a microservices architecture?
- How would you handle a region-wide outage?
- What monitoring and alerting would you set up on day one?
Practice a Similar Problem on Codemia
Solve a related problem with our interactive workspace, get AI feedback, and view detailed solutions.
Solve on CodemiaSample Answer
Requirements
Functional Requirements
- Real-time Search: Users should be able to perform property searches with filters such as location, price range, property type, etc.
- Autocomplete Suggestions: ...
Capacity Estimation
To estimate capacity, consider the following:
- User Base: Assume Redfin has 10 million active users.
- Daily Search Requests: If each user performs an average of 5 searches per day, that re...
Submit Your Answer
