Project: Agentic Orchestration Studio
Open Source Landscape
A comprehensive analysis of open-source tools that could form the building blocks of an orchestration platform for Aarhus Kommune.
Summary
No single open-source platform combines process mapping, orchestration, agent support, human-in-the-loop, and analytics in one product. Flowable comes closest — it uniquely combines BPMN/CMMN/DMN engines with a new agent engine and strong human task management. For a full platform, we need to compose multiple tools.
1. Workflow & Process Orchestration
| Tool | License | Self-hosted | Human-in-the-loop | Maturity | Best for |
|---|---|---|---|---|---|
| Apache Airflow | Apache 2.0 | Yes | Native (since 3.1) | Very high | Data/ML pipelines, scheduled workflows |
| Temporal.io | MIT | Yes | Via signals | Very high | Long-running stateful workflows |
| n8n | Fair-code | Yes | Via wait nodes | High | Visual automation, integrations |
| Windmill | AGPLv3 | Yes | Via approval steps | Growing | Fast execution, multi-language |
| Prefect | Apache 2.0 | Yes | Basic | High | Python data pipelines |
| Conductor | Apache 2.0 | Yes | Native | Medium-high | Massive scale, LLM integration |
Apache Airflow
Mature, battle-tested DAG-based orchestration. 25k+ GitHub stars. Airflow 3.1 (2026) added native human-in-the-loop with approve/reject operators. 32% of users now have GenAI/MLOps use cases. Python-only. Not designed for BPMN process mapping.
Temporal.io
Durable execution — workflows survive crashes and resume exactly where they left off. Code-first (Go, Java, Python, TypeScript, C#). Used by Stripe, Netflix, NVIDIA. No visual designer, requires developer skills. MIT licensed.
n8n
Visual workflow builder with 400+ integrations. Self-hostable, data stays on your infrastructure. Strong AI agent node (2026). Not designed for formal BPMN. Fair-code license (some enterprise features require paid license).
Windmill
13x faster than Airflow in benchmarks. Supports 10+ languages. Built-in app builder for dashboards. Suspend/resume releases workers. AGPLv3 community edition.
Conductor (Netflix/Orkes)
Built for billions of executions. Native AI/LLM integration with 14+ providers. Human-in-the-loop approval built in. Netflix handed maintenance to Orkes (commercial company).
2. BPM & Process Mapping
| Tool | License | BPMN 2.0 | Human tasks | Agent support | Notes |
|---|---|---|---|---|---|
| Flowable | Apache 2.0 | Full | Excellent | Yes (new engine) | Strongest overall candidate |
| Camunda 7 forks | Apache 2.0 | Full | Excellent | Via connectors | CIB seven, Operaton |
| jBPM | Apache 2.0 | Full | Excellent | Limited | Red Hat/IBM backed |
| BPMN.io | Permissive | Modeler only | N/A | N/A | Best visual editor, not a runtime |
Flowable (recommended)
Full BPMN 2.0, CMMN (case management), and DMN (decision tables) engines. Apache 2.0 open-source core. New agent engine (2025–2026) for multi-agent orchestration alongside BPMN/CMMN. Strong human task service with claiming, assignment, forms, delegation. Java-based, embeddable or standalone. The AI Studio and visual designer are commercially licensed — the engines are open source.
Camunda situation
Camunda 7 Community Edition is now End of Life. Camunda 8 requires a commercial license for production. Two open-source forks continue the Camunda 7 codebase:
- CIB seven — Apache 2.0, backed by CIB Group
- Operaton — Apache 2.0, community-driven
Both are viable alternatives if Flowable doesn't fit.
BPMN.io
Best-in-class web-based BPMN 2.0 visual modeler. Embeddable JavaScript library. Read/write standard BPMN 2.0 XML. Modeler only — not an execution engine. Pair with Flowable or similar for runtime.
3. Agent Orchestration
| Tool | License | Languages | Human-in-the-loop | Community | Notes |
|---|---|---|---|---|---|
| LangGraph | MIT | Python, JS | First-class | Very high (126k+) | Most popular, graph-based |
| CrewAI | MIT | Python | Supported | High (45k+) | Role-based agents, fast |
| MS Agent Framework | MIT | .NET, Python | First-class | High (27k+) | Just hit 1.0 (April 2026) |
LangGraph / LangChain
Most popular agent framework. Graph-based stateful orchestration. Human-in-the-loop is first-class — workflows can be interrupted, state inspected/modified, then resumed. Deep Agents (2026) for planning and subagents. MCP integration. LangSmith (observability) is commercial.
CrewAI
Role-based multi-agent collaboration. 5.76x faster than LangGraph in some benchmarks. MIT licensed, no LangChain dependency. 100+ tools, memory management. Event-driven Flows for complex pipelines.
Microsoft Agent Framework (AutoGen + Semantic Kernel)
Production-ready 1.0 shipped April 2026. Multiple orchestration patterns (sequential, concurrent, group chat, handoff). Workflow pause/resume for external input. A2A and MCP support. .NET and Python. Enterprise validation (KPMG, BMW).
4. RPA
| Tool | License | Platform | Visual designer | Notes |
|---|---|---|---|---|
| Robot Framework | Apache 2.0 | Cross-platform | No | Most mature, keyword-driven |
| TagUI | Apache 2.0 | Cross-platform | No | Simple, AI Singapore |
| OpenRPA | MPL 2.0 | Windows only | Yes | Drag-and-drop, OpenFlow integration |
Robot Framework (recommended)
Mature, widely-used. Keyword-driven (accessible to non-developers). Extensive library ecosystem (browser, desktop, Excel, APIs). Python-extensible. No built-in orchestration — needs a separate scheduler/orchestrator. Free forever.
OpenRPA
Visual drag-and-drop designer. Windows automation (SAP, Java, browsers, Office, mainframes). Integrates with Node-RED (OpenFlow) for orchestration. Smaller community, single primary maintainer.
5. Low-Code & Integration
| Tool | License | Integrations | AI support | Self-hosted |
|---|---|---|---|---|
| n8n | Fair-code | 400+ | AI agent node | Yes |
| Activepieces | MIT | 644+ | Native AI agents, MCP | Yes |
| Automatisch | AGPL-3.0 | ~50 | No | Yes |
n8n (recommended for integration layer)
400+ integrations, visual builder, self-hostable. Strong AI agent node. Data stays on infrastructure. Fair-code license means some enterprise features require payment, but the community edition is comprehensive.
Activepieces
644+ integrations, MIT core. All 280+ connectors available as MCP servers. Growing rapidly, but less mature than n8n.
Feature Comparison Matrix
| Capability | Flowable | n8n | LangGraph | Airflow | Temporal | Conductor |
|---|---|---|---|---|---|---|
| Visual process mapping (BPMN) | Yes | No | No | No | No | No |
| Process execution | Yes | Yes | Yes | Yes | Yes | Yes |
| Human-in-the-loop | Excellent | Basic | Excellent | Good | Good | Good |
| AI agent orchestration | Yes (new) | Basic | Excellent | Limited | Limited | Good |
| 400+ integrations | No | Yes | No | Limited | No | No |
| Case management (CMMN) | Yes | No | No | No | No | No |
| Decision tables (DMN) | Yes | No | No | No | No | No |
| Analytics dashboards | Commercial | Basic | Commercial | Good | Basic | Basic |
| Self-hosted | Yes | Yes | Yes | Yes | Yes | Yes |
| License | Apache 2.0 | Fair-code | MIT | Apache 2.0 | MIT | Apache 2.0 |
Denmark & Public Sector Considerations
OS2 alignment
Aarhus Kommune is part of the OS2 network (84% of Danish municipalities). Any solution should follow OS2 principles:
- Open source, prevent vendor lock-in
- Shared development across municipalities
- 25 open-source products already shared across 98 municipalities
Building an orchestration platform as an OS2 product would multiply the value and share the development cost.
Data sovereignty
Self-hosted solutions are essential for GDPR compliance and municipal data policies. All recommended tools support self-hosting.
Denmark's Digitalisation Strategy (2026)
DKK 740M budget with focus on AI advancement. An Agentic Orchestration Studio aligns directly with this strategy.
Sources
- Flowable — GitHub — Open Source
- BPMN.io — GitHub
- LangGraph — GitHub
- CrewAI — GitHub
- Microsoft Agent Framework — GitHub
- n8n — GitHub
- Activepieces — GitHub
- Apache Airflow — Airflow 3.1 HITL
- Temporal.io — GitHub
- Conductor OSS — GitHub
- Robot Framework — RPA Framework
- OpenRPA — GitHub
- CIB seven (Camunda 7 fork)
- Operaton (Camunda 7 fork)
- OS2 Denmark