Production engineering
Trace listener registration, cleanup, reconnection, and the evidence that separates transport duplication from client duplication.
CASE 001 / Incident file
The event that happened twice
A harmless-looking reconnection crosses runtime behavior, ownership boundaries, user workflows, and business correctness.
INCIDENTWebSocket lifecycle and duplicate processingSeries opening
01 / Mechanism
Follow the duplicate.
The visible symptom occurs at the end. The ownership mistake starts earlier in the connection lifecycle.
01Server event
02Connection A
03Reconnect
04Connection B
05Duplicate effect
02 / Perspectives
One mechanism, four consequences.
Each episode can stand alone on LinkedIn. Together they expose the complete system problem.
Architecture in practice
Decide which boundary owns the connection and how one active subscription becomes an enforceable invariant.
Product engineering
Follow the duplicate event into notifications, user decisions, task state, and the meaning of an action in progress.
Business value
Test the explanation against observable evidence and connect technical duplication to support cost and trust.