I started by outlining the key requirements for a file storage system: scalability, fault tolerance, and user sharing features. Suggested a microservices architecture using S3 for storage and DynamoDB for metadata management.

Discussed trade-offs of consistency vs. availability, especially in a globally distributed system.

The interviewer was engaged, asking about conflict resolution in versioning and how to handle file sync effectively. I provided examples from previous projects, which seemed to resonate well with them, but I struggled with some specifics on syncing algorithms, which led to more probing questions.