How a Silent Notification Bug Silently Rolled Back Bid Acceptances in a Spring App

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A software developer discovered a critical race condition bug where bid acceptances on a brand-publisher platform appeared to succeed but were silently rolled back. The root cause was a Spring @Transactional method that included an external HTTP notification call, meaning any network or service failure during notification would undo the entire database transaction. As a result, bids remained in SUBMITTED state, partnerships were never created, and neither brands nor publishers received feedback on what went wrong. The fix involved wrapping notification calls in a try-catch block, treating them as best-effort operations that should never block or reverse a successful database write. Two additional bugs were also uncovered during the investigation: a missing guard in commission calculations and a display priority issue when publishers held multiple bids on the same campaign.

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