A function that produces domain events from non-domain events. For example, if you need to generate a domain event from an event received from SQS queue, SNS topic, S3 event, API Gateway Event or Webhook, then we call that a trigger function. For the case of a Kinesis stream from Change-data-capture (CDC) (i.e. user updated in dynamo, and leads to dynamoDb->Kinesis stream), we will also use the naming "Trigger" because it is creating a domain event from non-domain events (CDC dynamoDb->Kinesis stream).
A function that consumes domain events from a kinesis stream that originated from an event hub.
An ingress flow is responsible for integrating with an external system to receive external domain events and transform them into internal domain events so that our system can react as needed.
An egress flow is responsible for reacting to an internal domain event and integrating it with an external system