The engineering decisions are the same. The consequences are not.
| You decide to | In SaaS | In SaMD |
|---|---|---|
| Split a service | An infrastructure decision. Deploy and move on. | Software item decomposition. New classification and verification artifacts for each piece. |
| Add a vendor or managed service | Check the SLA and integrate. Hours to days. | SOUP assessment or supplier qualification (ISO 13485 clause 7.4) before it touches clinical data. |
| Move to event-driven | An architecture pattern. The schema evolves as needed. | Software interfaces under IEC 62304. A breaking schema change is a change control event. |
| Add a caching layer | Performance optimisation. The usual invalidation problem. | A hazard scenario. Stale clinical data needs an ISO 14971 risk control. |
Every structural decision is also a regulatory decision. Teams that know this early move faster, because they stop discovering it at submission.
Seen this differently?
Questions, corrections and counterexamples are welcome.
