Race Conditions [Video]

A race condition is a concept where an outcome is dependent on the sequence or timing of other events.

For example, if the desired sequence of events is “Event A” and then “Event B”, but sometimes “Event A” comes first and other times “Event B” comes first—that is known as a race condition.

In Braze, one of the most common race conditions occurs with messages that target newly created users. Here, the expected order of events is:

1. A user gets created;
2. The same user is immediately targeted for a message, performs a custom event, or logs a custom attribute.

However, in some cases, the second event will trigger first. This means that a message is attempting to be sent to a user that has not been created yet, and as a result, the user never receives it. The same applies for events or attributes, where the event or attribute is attempting to be logged …