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Microsoft·Software Engineer·Onsite - System Design / Architecture·Senior

Senior
May 2026

Summary

Microsoft system design round for a software engineering role. The whole session was one big open-ended question about building a sports team recommendation system, and they really wanted you to drive the conversation across data, modeling, ranking, and scaling.

Questions Asked (1)

Q1

Design a recommendation system that suggests local sports teams to users, covering data ingestion, user and team modeling, ranking, and how the system scales.

System DesignData ModelingTechnical Trade-offs
Author's notes

This question sprawls in every direction and that's kind of the point.

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AI HintsAI Generated

Suggested Approach

Start by clarifying requirements and constraints, then walk through the high-level architecture covering data ingestion, user/team modeling, ranking, and scaling. Emphasize trade-offs and justify design choices with respect to Microsoft's scale and ecosystem.

Pro tip: Show awareness of cold-start and feedback loops by proposing hybrid approaches (content-based + collaborative filtering) and online learning to adapt to user behavior. Also, mention leveraging Azure services (e.g., Event Hubs, Cosmos DB, Machine Learning) to align with Microsoft's stack.

1. Clarify Requirements and Scope

Ask about scale (users, teams), data sources, real-time vs batch, and success metrics. Define functional and non-functional requirements.

2. Design Data Ingestion Pipeline

Outline how to collect user interactions (clicks, follows, views) and team data (schedules, stats, location) from various sources. Discuss batch and stream processing.

3. Model Users and Teams

Describe feature engineering for users (demographics, location, preferences) and teams (sport, league, popularity, local relevance). Explain how to create embeddings and handle cold-start.

4. Ranking and Recommendation Generation

Explain candidate generation (e.g., collaborative filtering, content-based) and ranking (e.g., learning-to-rank). Discuss blending multiple signals and personalization.

5. Scaling and System Architecture

Describe how to scale each component (e.g., sharding, caching, distributed processing) and ensure low-latency serving. Mention monitoring, A/B testing, and feedback loops.

Key Points to Mention

  • Hybrid recommendation approach combining collaborative filtering and content-based methods
  • Handling cold-start for new users and teams via location and popularity priors
  • Real-time vs batch processing for data ingestion and model updates
  • Scalable architecture using distributed systems (e.g., Kafka, Spark, Redis) and cloud services
  • Evaluation metrics (CTR, engagement, retention) and online experimentation
  • Privacy and ethical considerations in user data handling

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.