Skip to main content

Plexus Interop

Plexus Interop is an open-source interoperability framework for desktop applications that enables cross-application integration, messaging, and UI composition in financial and enterprise environments.

  • Inter-application communication framework for desktop environments (application integration)
  • Support for request/response, broadcast, and streaming communication patterns (messaging middleware)
  • Discovery and registration of services and applications through an interop registry (service discovery)
  • Support for integrating legacy and modern applications via adapters and APIs (systems integration)
  • Focus on interoperable workflows across multiple vendors and platforms within financial institutions (enterprise integration)

More About Plexus Interop

Plexus Interop is an interoperability framework (application integration) under the Fintech Open Source Foundation (FINOS) that targets desktop application integration, with a focus on financial services use cases. It addresses the problem of siloed desktop applications that need to share data, trigger actions in each other, and participate in joint workflows without being tightly coupled or rewritten. The project provides a common model and tooling for applications from different vendors or technology stacks to communicate and compose user interfaces on the same desktop.

At its core, Plexus Interop defines protocols and APIs (messaging middleware) for inter-application communication such as request/response, publish/subscribe, and streaming interactions. Applications can register services they provide and discover services exposed by other applications through an interop registry (service discovery). This registry maintains metadata about available commands, data types, and endpoints so that applications can bind to each other in a structured and typed manner rather than via ad hoc integrations.

The project includes components for wiring together heterogeneous applications (systems integration), including support for integrating both legacy and modern systems. Adapters and bindings allow existing applications to participate in the interop environment without major redesign, while new applications can integrate natively using the framework APIs. The project documentation describes service definitions and contracts that can be shared across teams and vendors, enabling consistent and reusable integration patterns.

Plexus Interop is designed for enterprise desktop environments (enterprise application integration), particularly in capital markets and trading workflows where users operate multiple specialized tools simultaneously. It allows one application to invoke functionality in another, pass contextual data such as instrument identifiers or orders, and coordinate composite user journeys across several windows and components. This capability supports scenarios like cross-launching applications with context, synchronizing views, and orchestrating multi-step workflows across a desktop estate.

From an architectural perspective, Plexus Interop can be positioned in the category of desktop interoperability frameworks and service-oriented integration tools (integration middleware). It aligns with FINOS efforts to standardize interoperability in financial desktops and can coexist with other open standards promoted by the foundation. For enterprise stakeholders, the project offers a structured model for decoupled, contract-based integrations, reducing one-off point-to-point connections between vendor and in-house tools while enabling consistent governance over how applications communicate and share context on user desktops.