Design a real-time Inventory Management System
Last updated: May 18, 2026
Quick Overview
Design a real-time inventory management system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.
Netflix
May 18, 202638
5
3,272 solved
Design a real-time inventory management system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.
ML system design at Netflix goes beyond model selection. This Onsite question evaluates your ability to design end-to-end ML pipelines, from data collection to model serving, while considering production constraints like latency and reliability.
What the Interviewer Expects
- Design the full ML lifecycle from data collection to model monitoring
- Address cold start, exploration/exploitation, and model freshness
- Discuss multi-objective optimization and ranking systems
- Plan for model debugging, fairness, and bias mitigation
- Design the feature store and training pipeline for scale
- Address model versioning, canary deployments, and rollback strategies
- Discuss the data flywheel and long-term system evolution
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
- What would you do if model performance degrades over time?
- How would you handle the cold start problem?
- How would you debug a model that works well offline but poorly online?
- How would you ensure fairness and reduce bias in the model?
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 Inventory Tracking: The system should continuously track the availability of titles, including movies and series, across all regions.
- *User Management...
Capacity Estimation
Assuming Netflix has approximately 230 million subscribers:
- Assumption of Requests: If each user makes about 5 requests per day for inventory checks, that results in:
- `230 million users * ...
Submit Your Answer
