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  Introduction Lors de la conception de workflows BPMN avec des moteurs comme Camunda , un problème fréquent est que l'exécution du processus reste bloquée au niveau d'une passerelle parallèle (Parallel Gateway) . Le modèle BPMN peut sembler correct, mais l’instance du processus n’avance plus . La raison principale est la gestion des jetons (tokens) dans les passerelles parallèles. Une passerelle parallèle (AND Gateway) divise le processus en plusieurs chemins exécutés en parallèle et attend ensuite que tous les jetons arrivent avant de continuer. Si un seul jeton manque, l’exécution reste bloquée indéfiniment . Fonctionnement d'une Passerelle Parallèle 4 Une passerelle parallèle fonctionne de deux manières: 1️⃣ Division (Fork) Un jeton entrant est divisé en plusieurs jetons exécutés en parallèle. Exemple : Tâche A | Passerelle Parallèle / \ Tâche B Tâche C Les tâches B et C s'exécutent en même temps. 2️⃣ Synchronisation (Join) La passerelle attend tous...

 Introduction While designing BPMN workflows in engines like Camunda, one of the most common runtime issues developers encounters is process execution getting stuck at a Parallel Gateway . At first glance, everything may look correct in the model, but the process instance never moves forward. Understanding how tokens behave at a parallel gateway is the key to solving this problem. A Parallel Gateway (AND Gateway) splits the workflow into multiple parallel paths and synchronizes them later. The workflow continues only when all incoming sequence flows reach the gateway . If one token never arrives, the process waits indefinitely , causing the execution to appear stuck. BPMN Parallel Gateway Basics A parallel gateway works in two ways: 1️⃣ Split (Fork) One incoming token creates multiple parallel tokens. Example: Task A | Parallel Gateway / \ Task B Task C Both Task B and Task C execute simultaneously. 2️⃣ Join (Synchronization) A joining parallel gateway waits for tok...

 🚀 Introduction In BPMN (Business Process Model and Notation), gateways control the decision-making and synchronization within a process flow. Camunda BPM implements these gateways exactly according to the BPMN 2.0 specification. In this blog, we will learn: ✔ What each gateway means ✔ When to use which type ✔ How Camunda executes them internally ✔ Real-world workflow examples 🧩 What Are Gateways in BPMN? Gateways are decision and routing points . They determine how the process should continue , based on: Conditions Parallel paths External events Complex logic 🔀 Types of Gateways in Camunda BPM There are 5 major BPMN gateways : Gateway Icon Use Case Exclusive Gateway (XOR) ❌ Only one path is taken Inclusive Gateway (OR) 🟢 One or more paths can be taken Parallel Gateway (AND) ➕ All paths start in parallel Event-Based Gateway ⏳ Waits for external events Complex Gateway ⚙️ Advanced logic / conditions Let’s understand each one. 1️⃣ Exclusive Gateway...