The Interoperability Imperative: Why Tech Decisions Are Now Business Decisions

The Interoperability Imperative:
Why Tech Decisions Are Now Business Decisions

At a recent practitioner workshop at The Composable Conference, we tackled one of the most pressing and complex challenges in enterprise architecture today: interoperability. We discussed the deceptively simple question: Should you insulate legacy systems - or chip away at them?

For the panel session I was joined by Kyle Barz, Senior Director of Enterprise Architecture at Mars and Yefim Natis, CEO at Natis Labs (and a former Gartner Fellow.)

What emerged from our discussion wasn’t a binary choice, but a shared conviction: Interoperability isn’t a feature of your architecture - it’s a function of your strategy.

The case for chipping away: Modernizing and replacing

Most organizations have a mix of legacy systems, self-built solutions, and newer composable elements. And for most, modernizing legacy systems is not optional. It's a strategic imperative. The panel began the session by discussing how interoperability - the ability for business teams to efficiently and effectively operate across different systems in their technology stack - is a continuous evolution, not a one-time transformation. Too often, interoperability is considered at the technical level (system APIs) only, not putting sufficient emphasis on the goal it serves: the business capabilities, use cases, and ease of navigating them.

So, how do you prioritize which systems to modernize?

One way is to focus on business capabilities that drive differentiation, especially those close to the customer or consumer. These are the most strategic areas to evolve, where speed, agility, and innovation can have a real impact.

When deciding whether to patch or replace, we agreed that it’s essential to weigh the total cost and time of both options. Remember that maintaining legacy systems often adds complexity, slows progress, and limits agility - an opportunity cost that we can easily deny because it is so hard to track on a spreadsheet. Modernization, in any case, must serve a long-term vision.

A composable approach enables modular, incremental change, allowing brands to build reusable and replaceable technologies that can serve multiple services, as well as scale modernization efforts over time. Agility comes from the ability to solve today’s problems while continuously evolving on the same foundational architecture to anticipate and scale for future needs.

The case for “insulating”: Conscious delay

While not everything can or should be modernized at once, the panel discussed a more pragmatic path of insulating certain legacy systems - one that contains and limits their role temporarily while focusing modernization efforts on high-priority areas.

This may involve wrapping older systems with APIs or event-driven mechanisms so they can still interact with modern components, without a full rebuild. This can buy time and reduce disruption, especially when budgets are tight or when systems are not directly involved in strategic differentiation.

Insulating also creates breathing room to experiment with new architectures. Starting small and showing early success builds internal confidence, proves value, and can unlock broader buy-in. As Kyle explained, composable thinking at Mars includes decomposing legacy processes into individual capabilities - a process that takes time and organizational change, especially around ownership and governance.

Beyond architecture: The strategic lens on interoperability

Throughout the session, one idea stood out: interoperability is not just a technical issue - it’s a strategic imperative. Poor interoperability doesn’t just slow systems down. It slows transformation, hinders innovation, limits experimentation, disconnects teams, and degrades customer experience. In contrast, effective interoperability accelerates time-to-value, enables smarter investment decisions, and supports a more adaptive, future-ready enterprise.

To get there, though, is a mindset shift.

Composable architectures aren't just about the tech stack - they represent a new model of working where business and IT are no longer siloed. Which raised the question: “Who is the composer?” In the old Service-Oriented Architecture (SOA) world, it was the developer. In today’s composable model, the composer is a business technologist - someone who blends technical fluency with business acumen to assemble capabilities that drive outcomes.

Kyle highlighted that this “fusion team” approach, where IT is federated across the business, is one Mars is actively pursuing. Digital champions are embedded in business units, building trust and moving faster without waiting on a central IT mandate.

Looking ahead: AI, governance, and the cost of inaction

The panel struck a note of caution about experimenting with tools like ChatGPT without an intentional AI strategy. The risk can be data leakage and disjointed experiences. The good news is that organizations already invested in composable architectures are better prepared. Their systems are modular, their processes are explicit, and their data flows are structured - all critical for deploying AI agents responsibly and effectively.

Another key part of modernization raised in the session was governance. Organizations need clear oversight of their system interfaces, endpoints, and addresses. Maintaining a catalog of these connections is essential, especially in a composable environment where different protocols, interfaces, and data models must coexist and interact seamlessly.

Finally, when it comes to securing budget and buy-in for modernization, it was agreed that the most compelling case is understanding the total cost of ‘inaction’. Persevering with outdated legacy systems will quietly drain resources, slow innovation, and leave businesses exposed. Showing what’s at risk - not just what’s possible - can be the tipping point for investment.

Composable thinking is a mindset

While there might not be a definitive correct answer to the “insulate or chip away” dilemma, our session revealed a guiding principle: interoperability is a journey of continuous evolution. Some systems must be modernized now while others can wait. What matters is aligning those decisions with strategic priorities, customer needs, and long-term business goals.

At its core, composable thinking is a mindset - one that embraces dynamic, interacting components and prepares organizations to work effectively with agents and AI.

It enables organizations to treat digital transformation not as a one-off project, but as a living, adaptable system. And in a world where technology is the strategy, that may be the most critical capability of all.

The Interoperability Imperative