PubNub does not guarantee message order and in general does not guarantee that they are stored or sent in the exact same order in which they are published. If your application requires messages to be processed in the same order they were published, it is recommended to add a sequence field to the message payload and use it to order messages when received they are received by the subscriber.

From a practical standpoint, as long as the publisher sends messages at a slower rate than the consumer can receive them, you can assume with high confidence that messages will be kept in order.

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