Concurrency Bug

Definitions

1. A defect caused by incorrect coordination between concurrent operations, such as race conditions, deadlocks, lost updates, or visibility issues. Concurrency bugs are notoriously hard to reproduce because they often depend on specific timing and scheduler behavior rather than deterministic input alone.

   In plain English: A bug caused by multiple operations interacting incorrectly at the same time.

   Example: "The duplicate charge incident came from a concurrency bug where two workers both observed the order as unprocessed before either one committed its update."

Related Terms

• Race Condition
• Deadlock
• Lock
• Main Thread
• Monitor
• Overflow
• Shared State
• Thread Local
• Thread Safety