README.md

Zeebe

Zeebe is the process automation engine powering Camunda 8. While written in Java, you do not need to be a Java developer to use Zeebe. To learn more about Zeebe, visit the Camunda docs.

Modules

This is a small overview of the contents of the different modules:

• util contains custom implementations of building blocks like an actor scheduler, buffer allocations, and metrics. Its parts are used in most of the other modules
• protocol contains the SBE definition of the main message protocol
• bpmn-model is a Java API for BPMN process definitions used for parsing etc.
• msgpack-* is a custom msgpack implementation with extensions to evaluate json-path expressions on msgpack objects
• dispatcher is a custom implementation of message passing between threads
• service-container is a custom implementation to manage dependencies between different services
• logstreams is an implementation of an append-only log backed by the filesystem
• transport is our abstraction over network transports
• gateway is the implementation of the gRPC gateway, using our SBE-based protocol to communicate with brokers
• gateway-protocol contains the gRPC definitions for the Zeebe client-to-gateway protocol
• zb-db is our RocksDB wrapper for state management
• engine is the implementation of the event stream processor
• broker contains the Zeebe broker which is the server side of Zeebe
• client-java contains the Java Zeebe client
• atomix contains transport, membership, and consensus algorithms
• benchmark contains utilities the team uses to run load tests
• exporters/elasticsearch-exporter contains the official Elasticsearch exporter for Zeebe
• journal contains the append-only log used by the consensus algorithm
• snapshots abstracts how state snapshots (i.e. zb-db) are handled