EventTopic — Local

Source: reventless-local/src/adapter/EventTopic/LocalEventTopicPublisher.res

AWS equivalent: EventTopic → SNS

How It Works

Events are published to the shared LocalBus using Bus.publishEvent. The bus fans out events to all subscribers using Effect's PubSub primitive. The topic name (set during make) is used as the bus topic key.

The adapter returns a dummy resource with the topic name, which LocalEventCollectorChannel uses to subscribe to the correct bus topic.

Operations

Operation	Description
publishJson	Publishes a single event to the bus topic
publishJsonStream	Stream variant — groups items into batches of 10

Key Differences from AWS

Aspect	Local	AWS
Transport	Effect PubSub fan-out	SNS topic
Delivery	Synchronous (2-3 microtask ticks)	Asynchronous SNS → SQS
Subscribers	Bus subscribers	SNS subscriptions (SQS, Lambda, etc.)
Fan-out	Unbounded or bounded PubSub	SNS unlimited subscriptions