Debugging Lost Chat Notifications for Offline Users with Durable Cursors

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Lost notifications for offline users in a financial chat should be investigated by first examining the durable record and cursor rather than the live connection. The recommended design commits each notification to an ordered room log before attempting best-effort delivery, so clients can replay events after their last acknowledged cursor on reconnect. Ephemeral publishing suits transient states like typing or presence, where loss is acceptable, while messages and payment notices need durable storage. A root-cause checklist starts with confirming the business event was committed, then the record append, the subscriber's cursor and token claims, and only finally the live socket. A worked example shows how a gap in sequence numbers lets the client stop and surface a fault instead of silently advancing.

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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