State and Side-Effect Decision Examples

Positive example — owned transition and effect

• Context: one operation updates durable state and schedules an external notification.
• Mode: single-owner-mutation.
• Decision: one owner validates and commits the transition, then records the notification handoff explicitly.
• Why it fits: mutation and effect ordering have one accountable owner.

Negative example — speculative CQRS

• Context: one process maintains a small record with identical read and write needs.
• Mode: pragmatic-mutable.
• Bad decision: add command buses, events, projections, and eventual consistency.
• Better decision: keep one model and explicit local transitions.