Explicit interaction
Use point-to-point calls when an immediate answer and direct responsibility are clearest. Use events when independently owned components need durable facts, decoupling, replay or multiple reactions.
Approach
Enterprise design is not a collection of empty services. It is clear responsibility, explicit interaction, bounded authority and evidence about what happens when things go wrong.
Use point-to-point calls when an immediate answer and direct responsibility are clearest. Use events when independently owned components need durable facts, decoupling, replay or multiple reactions.
Workload identity, least privilege and network policy apply between components, not only at the public edge.
Changeable privacy, disclosure and operational rules remain outside service code where doing so improves review, testing and ownership.
Rust is preferred where its safety and reliability characteristics provide meaningful value for backend services and shared components.
Portable rules, transformations, scenario automation and integration logic may use cREXX when the trust boundary and operational value are explicit.
Static sites use managed hosting. Small dynamic capabilities can scale to zero on Cloud Run. Kubernetes is reserved for demonstrations that need its boundaries and operating model.
The Scenario Director
The Director can reset synthetic state, introduce an event, pause the scenario and present evidence. Domain components remain responsible for their own decisions and expose those decisions through commands, events and evidence.