Concurrent / Multi-threaded Log Writer

Problem Overview

Implement a thread-safe log writer (also called a 'system programming' or 'low-level coding' problem at Databricks). Multiple threads share a single logger instance and call a write() method concurrently. Core requirements: (1) all threads can write log entries simultaneously without data corruption; (2) each write() call must guarantee the data…

• 5 candidate-reported follow-ups — the exact probes interviewers asked, with the trigger for each
• The rest of the problem statement — full requirements, constraints, and edge cases
• Approach and trade-offs — what passing candidates did, and the mistakes that sink people