Is Your Software Architecture Ready for Your Medical Device to Change?
Medical device software should not only satisfy today's requirements. Its architecture should make future hardware, software, connectivity, and feature changes manageable. Early software architecture advisory can reduce technical risk, avoid expensive redesigns, and prepare a medical device for long-term development. The goal is to design for change, not only for the first release.
Impact of Changes
Every software change needs to be understood, assessed, and tested. With poorly structured software, even a relatively small update can have unclear consequences across the system.
Under the currently published IEC 62304, the software system is assigned a safety class, and software items generally inherit that classification unless documented architectural segregation supports a different classification. When software is changed, the manufacturer must analyse the impact of the modification, update the relevant documentation and configuration records, consider its effect on risk controls, and repeat the necessary lifecycle activities. Depending on that analysis, these activities may include regression testing to demonstrate that existing functions and risk controls have not been adversely affected.
Software configuration management also supports the identification and version control of software configuration items, including relevant third-party software and SOUP. Together with ISO 14971 risk management, these processes help determine whether a change introduces new hazards, affects existing risks, or compromises implemented risk controls. A well-structured architecture makes affected software items and interfaces easier to identify, allowing verification to remain focused while providing evidence that the device continues to perform safely. The draft direction for IEC 62304 Edition 2 reinforces this point by proposing architecture planning for all software process rigor levels, not only for higher-risk software.
Medical Devices Are Built to Evolve
Usually, the first release is only the beginning of a product lifecycle. After market launch, medical devices continue evolving through new features and integrations, hardware revisions, new sensors, connectivity and cloud, algorithm updates, and AI development. Customer and market requirements change, and it's the architecture that determines how difficult these specific changes turn out to be.
Good architecture identifies which of these areas are likely to change and creates boundaries around them, so that a sensor swap, a new cloud feature, or an AI model update doesn't touch parts of the system that were never meant to be touched. You don't need to predict every future requirement, you need an architecture that keeps one future change from affecting the entire system.
Typical architectural techniques include modularization, interface-based design, hardware abstraction, service separation, and controlled dependency management. These approaches help contain the impact of change and reduce the scope of verification activities when modifications are introduced.
Before choosing a software architecture, it is worth looking beyond the first release.
Planning Around the Product Map
Before choosing a software architecture, it is worth looking beyond the first release. This is also where experienced software advisory can help turn a product roadmap into the right technical decisions.
Key questions include:
- Are additional product or hardware generations planned?
- Could sensors or other components change?
- Will cloud connectivity or remote updates be needed?
- Is AI/ML functionality part of the roadmap?
- Will the device communicate with external systems?
- Which parts of the software are most likely to evolve?
- Which safety-critical functions should remain isolated?
- These questions help determine what the architecture needs to support from the beginning.
Summary
Software architecture affects the entire product lifecycle, making it more than a development decision. It is a long-term product decision. Medical devices evolve, and architecture cannot prevent that. What good architecture can do is make change easier to introduce, understand, test, and manage.
The best time to identify an architectural problem is before it becomes a development problem. Thaumatec supports MedTech teams before expensive technical decisions are locked in, through reviewing the product roadmap, architecture, and technical risk together, and helping build software foundations that leave room for tomorrow's innovation, not just today's release.