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A signed webhook passes locally but fails after JSON middleware is added. Diagnose it without weakening verification.

Both payloads parse to the same object. Only one authenticates. Trace the bytes, endpoint secret and timestamp before replaying the customer's missed events.

Updated Oct 2026 · Grounded in real Forward Deployed Engineer interview loops and written to a senior-engineer editorial bar.

Both payloads parse to the same object. Only one authenticates. Trace the bytes, endpoint secret and timestamp before replaying the customer's missed events.

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