How Camunda 8 Stores Workflow State (Zeebe Internals Explained)
Zeebe Architecture Overview ✍️ Introduction If you’re coming from Camunda 7 (DB-based engine) , understanding how Camunda 8 (Zeebe) stores workflow state is a game changer . Instead of storing process state in a relational database, Zeebe uses a distributed event-driven architecture — making it: ⚡ Highly scalable 🔁 Fault tolerant 🚀 Extremely fast 👉 Let’s break this down in a simple, practical way . 🧩 1. Core Idea: Event-Sourced State In Zeebe: ❌ No central database ✅ Workflow state = event stream (log of events) Every action in a workflow becomes an event : Process started Task activated Variable updated Task completed These events are written sequentially to a log . 📌 This is similar to Kafka-style architecture. 👉 Zeebe stores state as event streams on disk across brokers 🖼️ Event Stream Concept ⚙️ 2. How State is Actually Stored Let’s simplify: 🧱 Step-by-step Client sends command → via Gateway (REST/gRPC) Gateway routes to a Broker Broker writes an event: PROCESS_INSTANCE_C...