An UpdateEffect is a description of what Kalix needs to do after the command is handled. You can think of it as a set of instructions you are passing to Kalix. Kalix will process the instructions on your behalf and ensure that any data that needs to be persisted will be persisted.

Each Kalix component defines its own effects, which are a set of predefined operations that match the capabilities of that component.

A View UpdateEffect can either:

• update the view state
• delete the view state
• ignore the event or state change notification (and not update the view state)

Construct the effect that is returned by the command handler. The effect describes next processing actions, such as emitting events and sending a reply.