MICROSOFT · SYSTEM DESIGN
Microsoft system design interview questions
Formal design rounds start at Senior (63+) and are optional or light at SDE II. The prep page names distributed systems, service-oriented architecture, replication, partitioning, CAP and auto-scaling. Prompts often resemble Microsoft or Azure products.
Which levels get a design round
| Level | Microsoft title | Design round | Low-level design |
|---|---|---|---|
| SDE 1 | Software Engineer (59–60) | Usually not | – |
| SDE 2 | Software Engineer II (61–62) | Usually not | – |
| Senior Software Engineer (SDE 3) | Senior Software Engineer (63–64) | Yes | – |
| Staff Software Engineer | Principal Software Engineer (65–67) and above | Yes | – |
Design questions candidates report
-
Design a collaborative document editor
A LADDER walkthrough of a collaborative document editor: requirements, scale math for millions of concurrent editors, the API and an operation-log data model, then the hard parts: why concurrent edits conflict, operational transformation versus CRDTs, one session server per document, durability with an op log and snapshots, failover, offline edits, live cursors, version history and permissions.
Full walkthrough: Google Docs -
Design a cross-device file sync service
How to design a cloud file storage and sync service like Google Drive or Dropbox: requirements, storage and traffic math, splitting files into content-addressed blocks, resumable uploads and deduplication, separating metadata from blobs, a change journal with cursors so every device syncs, push notifications, conflict handling and version history, sharing permissions, and the trade-offs.
Full walkthrough: Google Drive Practise on the design board -
Design a chat and presence service
A LADDER walkthrough of a mobile chat system: requirements, scale math for 20 billion messages a day and 200 million open connections, the WebSocket and REST API, a message store partitioned by conversation, then the deep dives: routing between chat servers, offline delivery and push, sent-delivered-read receipts, per-conversation ordering, group fan-out, presence, media and end-to-end encryption.
Full walkthrough: WhatsApp Practise on the design board -
Design a telemetry / log ingestion pipeline
How to design a metrics monitoring and alerting system for a hundred thousand machines: collecting samples by pull or push, a buffered write path, a time-series database with compressed chunks and an inverted label index, the cardinality trap, downsampling for long ranges, rule evaluation with pending periods, an alert manager that groups and silences, and how to monitor the monitor.
Full walkthrough: Monitoring and alerting
Also reported
- Design a distributed cache
- Design a feature flag service
How to answer any design question: the LADDER method · How the design round is scored by level
Questions people ask
When does Microsoft ask system design?
A design round is part of the loop for Senior Software Engineer (SDE 3) (Senior Software Engineer (63–64)), Staff Software Engineer (Principal Software Engineer (65–67) and above). Formal design rounds start at Senior (63+) and are optional or light at SDE II. The prep page names distributed systems, service-oriented architecture, replication, partitioning, CAP and auto-scaling. Prompts often resemble Microsoft or Azure products.
What system design questions does Microsoft ask?
Candidates report: Design a collaborative document editor; Design a cross-device file sync service; Design a chat and presence service; Design a telemetry / log ingestion pipeline; Design a distributed cache; Design a feature flag service.
System design questions at other companies
- Amazon
- Meta
- Apple
- Netflix
- Uber
- Airbnb
- Stripe
- Atlassian
- Goldman Sachs
- Salesforce
- Oracle
- Adobe
- Flipkart
- Walmart Global Tech
- PhonePe
- Swiggy
- Razorpay
System design questions across all companies · Behavioral questions