Softwr

APIs · head to head

Asyncapi vs Flowable

Asyncapi logo

Asyncapi

APIs

Specification and tools for defining asynchronous APIs

From
Free
Rated
-
Full reviewWebsite
Flowable logo

Flowable

Automation Integration

Apache 2.0 BPMN, CMMN and DMN engine from the team that originally built Activiti

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: Asyncapi complex to implement and debug asynchronous operations due to their non-linear and concurrent nature; Flowable the open source engine is genuinely usable but ships without the modelling studio, work application and admin console, so an open source deployment means building your own user interfaces before anyone can use it.
  • They diverge on capability: Asyncapi covers API Specification, Flowable covers BPMN 2.0 engine.
  • Prices and features above were last checked on 31 August 2026.

Where they differ

Only the attributes on which Asyncapi and Flowable actually diverge.

Attributes where Asyncapi and Flowable differ
AttributeAsyncapiFlowable
Pricing modelopen-sourcequote
PlatformsWeb, CLI, IDE ExtensionsLinux, Windows, Docker, Kubernetes, Cloud
CategoryAPIsAutomation Integration
Founded2019Unknown

Identical on both: starting price (Free), free tier (Yes), user rating (Not yet rated).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in Asyncapi

  • API Specification
  • Code generation
  • Documentation
  • Multiple messaging protocols
  • Code generators
  • Specification support
  • Tools support
  • CLI support

Only in Flowable

  • BPMN 2.0 engine
  • CMMN case management
  • DMN decision tables
  • Spring Boot integration
  • Modelling studio
  • Task and case application
  • REST APIs
  • History and audit

What people use each for

The jobs each tool is most often brought in to do.

Asyncapi

  • API Developmentnot Flowable
  • API Gatewaynot Flowable
  • API Testingnot Flowable
  • API Documentationnot Flowable
  • Microservicesnot Flowable

Flowable

  • An insurer automating claims handling where each case follows a different path and BPMN alone cannot express itnot Asyncapi
  • A bank embedding process orchestration inside an existing Spring Boot estate rather than buying a separate platformnot Asyncapi
  • A team leaving Activiti or jBPM that wants the same API family with active commercial maintenancenot Asyncapi
  • A regulated organisation needing complete process history and decision table audit trails for supervisorsnot Asyncapi

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

Asyncapi

  • Complex to implement and debug asynchronous operations due to their non-linear and concurrent nature
  • Keeping AsyncAPI documents up to date is challenging as systems evolve
  • Tracing and debugging asynchronous operations is more difficult than synchronous request-response patterns

Flowable

  • The open source engine is genuinely usable but ships without the modelling studio, work application and admin console, so an open source deployment means building your own user interfaces before anyone can use it.
  • It expects Java engineering capacity; teams looking for a business-user low-code automation tool will find the modelling and deployment cycle far too technical.
  • Enterprise pricing is not published and is quoted per deployment, leaving buyers without a benchmark against Camunda or IBM alternatives.
  • The Activiti fork left three engines with related APIs and overlapping documentation in circulation, and search results routinely return advice for the wrong one.
  • Flowable AG is a small Swiss company relative to its competitors, so the partner network, training market and pool of engineers with production experience are all limited outside Europe.

Pricing, plan by plan

Asyncapi

Free
  • Open SourceFree
    • AsyncAPI specification
    • Tools
    • Community support

Flowable

Free
  • Flowable Open SourceFree
    • Apache 2.0 licensed BPMN, CMMN and DMN engines
    • Embeddable Java library or standalone apps
    • No modelling studio or enterprise applications
  • Flowable Enterprise$undefined/year
    • Modelling studio, work application and admin console
    • Connectors, forms and advanced identity management
    • Support with SLA and version maintenance

Which should you pick?

Choose Asyncapi if

  • You need api specification.
  • You want to start without paying.
  • You work on Web, CLI, IDE Extensions.
  • You also want code generation.
Asyncapi review

Choose Flowable if

  • You need bpmn 2.0 engine.
  • You want to start without paying.
  • You work on Linux, Windows, Docker, Kubernetes, Cloud.
  • You also want cmmn case management.
Flowable review

Questions people ask

Is Asyncapi or Flowable better?
Neither clearly leads. Asyncapi starts at Free and Flowable at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Asyncapi or Flowable?
Asyncapi starts at Free and Flowable at Free.
Does Asyncapi or Flowable run on more platforms?
Asyncapi runs on Web, CLI, IDE Extensions. Flowable runs on Linux, Windows, Docker, Kubernetes, Cloud.
Can I use Asyncapi for free?
Both have a free tier, so you can try either at no cost before committing.
What is Asyncapi best used for?
Asyncapi is most often used for api development, api gateway, api testing, api documentation. Of those, api development and api gateway are not what Flowable is typically brought in for.
What can Asyncapi do that Flowable cannot?
Asyncapi covers API Specification, Code generation, Documentation, Multiple messaging protocols. Flowable covers BPMN 2.0 engine, CMMN case management, DMN decision tables, Spring Boot integration.

Answered from the vendors’ own pages

Asyncapi: What is AsyncAPI used for?

AsyncAPI is an open-source specification for defining and documenting asynchronous APIs, message-driven systems, and event-driven architectures. It serves the same purpose for async APIs as OpenAPI does for REST APIs, providing standardized documentation, code generation, and tooling.

Source
Flowable: Is Flowable open source?

Yes, the BPMN, CMMN and DMN engines are Apache 2.0. The modelling studio and enterprise applications are commercial.

Asyncapi: Is AsyncAPI free to use?

Yes, AsyncAPI is completely free and open-source. It is hosted by the Linux Foundation and supported by community contributions and sponsorships from companies like Postman, IBM, IQVIA Technology, and Solace.

Source
Flowable: How does it relate to Activiti and jBPM?

The same core developers built jBPM, then Activiti, then forked Activiti in 2016 to create Flowable.

Asyncapi: What protocols and technologies does AsyncAPI support?

AsyncAPI supports multiple protocols and technologies including Kafka, RabbitMQ, MQTT, Socket.IO, AWS EventBridge, and others. It provides language support for JavaScript/TypeScript, Python, Java, Go, C#/.NET, Kotlin, and PHP.

Source
Flowable: What does Flowable Enterprise cost?

Nothing is published. It is quoted per deployment by the vendor.

Asyncapi: Does AsyncAPI have IDE support?

Yes, AsyncAPI has IDE extensions available for VSCode and IntelliJ, along with CLI utilities and GitHub Actions integration for developers.

Source
Flowable: Why choose it over Camunda?

CMMN case management is a first-class engine, which matters when work is exception-driven rather than a fixed sequence.

Share

Related pages

More on Asyncapi

More on Flowable

Keep looking

Other head to heads