BPMN Support
Without BPMN support, migrating process models created in tools like Camunda Modeler, Signavio, or Bizagi means re-drawing every flow in the Workflow Engine Designer by hand - time-consuming, error-prone, and disconnected from how your team already works.
BPMN support is a plugin that reads BPMN 2.0 XML files and converts them into executable Workflow Engine schemes.
With BPMN support, you upload a BPMN diagram and the plugin produces a working scheme in the Designer, preserving the core flow structure - gateways, events, tasks, and sequence flows. For example, a purchase approval diagram modeled in Camunda Modeler becomes a Workflow Engine scheme ready to run against your persistence database, without re-drawing a single element.
What it is
Think of BPMN support as a translator between two languages. Your team draws processes in a familiar BPMN modeling tool - the standard notation for process design. Workflow Engine executes processes using its own scheme format. The BPMN plugin reads a BPMN 2.0 XML file and produces an equivalent Workflow Engine scheme, mapping each BPMN element type to the closest matching runtime construct.
| BPMN element | What it becomes in Workflow Engine |
|---|---|
| Start event | Initial activity (the first activity the runtime executes) |
| End event | Final activity (completes the process instance) |
| Service task | Intermediate activity with auto-trigger |
| Exclusive (XOR) gateway | Custom activity type - outgoing transitions act as conditional branches |
| Parallel (AND) gateway | Custom activity type - enables concurrent execution paths |
| Timer catch event | Intermediate activity with timer trigger |
| Message catch event | Intermediate activity that waits for an external command |
| Terminate event | Final activity that ends all parallel branches |
Import is not lossless. BPMN elements without a Workflow Engine equivalent - message flows between pools, complex gateways, boundary events, event subprocesses - are skipped during import. The BpmnPlugin logs each skipped element in the import results. Use BPMN import as a migration tool for the structural flow, not as a fidelity-preserving converter. The canonical editing format is Workflow Engine's native scheme format.
For developers: The BpmnPlugin implements IWorkflowPlugin and registers eight custom activity types (ServiceTaskActivity, ExclusiveGateway, ParallelGateway, MessageCatchEvent, TimerCatchEvent, StartEvent, EndEvent, TerminateEvent) plus a Designer action (bpmnplugin_uploadbpmn). Install the OptimaJet.Workflow.BpmnPlugin NuGet package and register the plugin with runtime.WithPlugin(new BpmnPlugin()). See the BPMN import guide for setup and element mapping details.
Why it matters
BPMN support delivers these outcomes:
- No process re-drawing - Import existing BPMN diagrams directly. A team migrating from Camunda Modeler to Workflow Engine does not need to re-author each flow. The import preserves gateways, events, tasks, and sequence flow structure.
- Single source of truth for process design - Process analysts can continue using their preferred BPMN modeling tool for design and documentation. The imported scheme is the executable version of the same diagram. No translation layer, no manual transcription.
- Faster migration from incumbent engines - Existing BPMN assets from legacy workflow products or BPMN-based services can be imported in bulk. The core flow structure migrates; only runtime-specific configuration (command bindings, rule assignments, code actions) needs manual setup.
Who it is for
Evaluator (CEO, CTO, PM): BPMN support removes the re-drawing bottleneck when migrating from BPMN-based workflow tools. If your team uses BPMN for process modeling and you are evaluating Workflow Engine, you can import your existing diagrams and evaluate against real processes, not toy examples.
Developer: The plugin reduces integration effort by translating BPMN XML to a runtime scheme in one step. You implement rule providers and action providers once - the same code works for imported and hand-authored schemes. See the BPMN support page for setup details and the full list of supported elements.
Enterprise architect: BPMN import preserves the structural intent of enterprise process models. Combined with Workflow Engine's persistence and clustering, you can model processes in BPMN-standard tools and deploy them on a horizontally scalable runtime without manual schema translation.
When to use it
Use BPMN import when existing process diagrams are in BPMN 2.0 format. Typical examples:
- Migrating from Camunda, Signavio, or Bizagi - You have hundreds of BPMN diagrams in production on another engine. Import each diagram to Workflow Engine, add runtime configuration (actions, rules, commands), and deploy. The core flow structure transfers; the runtime-specific wiring is new.
- Procurement or compliance documentation - Your compliance team maintains process documentation as BPMN diagrams in a modeling tool. Import the approved diagram to create the executable scheme, ensuring the running process matches the documented design.
- Partner or vendor process exchange - A partner provides integration workflows as BPMN 2.0 XML. Import the file directly rather than translating the flow manually into the Designer.
How it compares
The table below shows the tradeoffs between the Workflow Engine approach and the alternative.
| Approach | What it requires | Result |
|---|---|---|
| Re-author by hand | Copy each BPMN element into the Designer: re-create activities, transitions, gateways, and conditions manually | Time per process: hours. Risk of transcription errors. Divergence between design model and running process. |
| Workflow Engine BPMN import | Upload the BPMN 2.0 XML file through the Designer. Add runtime wiring (actions, rules) after import. | Minutes per process. Core flow structure preserved. Design model and running process stay in sync. |
Import fidelity depends on element complexity. Simple flows (start - tasks - exclusive gateway - end) import cleanly. Advanced BPMN constructs (complex gateways, boundary events, event subprocesses, pools and message flows) are not supported and are skipped with a log entry.
Frequently asked questions
Does Workflow Engine support exporting schemes as BPMN 2.0 XML?
Not currently. The BpmnPlugin is import-only. Schemes edited in the Designer or modified at runtime cannot be exported back to BPMN format. Use the Designer's built-in scheme export for backups and the Simple Process Notation for version control.
Do I need a specific license for BPMN import?
Yes. The BpmnPlugin checks for a BPMN license restriction at registration. If your license does not include BPMN support, the plugin throws on OnPluginAdd. See Workflow Engine Editions for per-feature license mapping.
Which BPMN 2.0 elements are not supported in import?
Complex gateways, event subprocesses, boundary events (attached to activities), pools and message flows, data objects, and artifacts are skipped. The import log lists each skipped element with the reason. Custom extension elements and non-executable BPMN attributes (documentation, graphical layout) are also ignored.
What happens to transitions and conditions during import?
Sequence flows become transitions. Conditions on exclusive gateway outgoing flows become the condition expressions on each transition. Parallel gateways produce concurrent outgoing transitions - the runtime executes all branches. The converter handles subprocesses by creating inlined schemes (sub-schemes referenced from the main process).