---
title: Observers
---

Observers are documented in the shared Chronicle docs. Use those pages for
the conceptual model and examples that apply across clients.

- [Observer concepts](/chronicle/concepts/observers/)
- [Reactors](/chronicle/reactors/)
- [Reducers](/chronicle/reducers/)
- [Projections](/chronicle/projections/)

For JVM syntax, see the [annotation
reference](/chronicle/clients/kotlin/reference/annotations/) and
[EventStore API
reference](/chronicle/clients/kotlin/reference/event-store-api/).