We don't apply DDD everywhere. We apply it where it genuinely changes the economics of delivery and operations:
Complex product platforms
Multiple teams, multiple channels, shared capabilities, and strong regulatory or operational constraints.
Event-driven and distributed systems
Where asynchronous flows, eventual consistency, and autonomy are essential—not optional.
Cloud and hybrid environments
Services spanning regions, clouds, and deployment models (including on-prem), with real-world latency and failure modes.
AI- and data-intensive domains
Where domain concepts, data contracts, and decision points drive models and explainability, not the other way around.
Legacy estates being modernised in-place
Where you can't just "rewrite" and need to incrementally carve out cleaner domains and interfaces.
If your system is simple and small, DDD is overhead.
If your system carries real-world complexity, DDD is how you stop it from collapsing under its own weight.