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Using an external PubSub Engine


graphql also supports any external PubSub system that implements the AsyncIterator interface.

By default graphql-subscriptions exports an in-memory (EventEmitter) event system to re-run subscriptions.

This is not suitable for running in a serious production app, because there is no way to share subscriptions and publishes across many running servers.

graphql-subscriptions - PubSub Implementations lists existing external PubSub implementations.