Why did full-state session bootstrap break for large organisations?
The initial payload grew roughly with users times channels, reaching tens of megabytes, built in one data centre on every connect. Reconnection storms after a network blip repeated that work for thousands of clients at once. A regional cache of team data removes the repeated computation.
Answered in
Real-Time Chat That Never Lies: Persist Before You Broadcast, and Cache the Cold StartWhy send flows must store a message before showing it, how an approximation of atomic broadcast works, and why session bootstrap needs an edge cache.
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