Tributary Concepts
Problem This Area Solves
Tributary exists to turn event streams into derived state without forcing reducer and snapshot mechanics into the stream layer or the domain layer.
Core Idea
Tributary is the reconstruction layer between raw streams and higher-level behavior.
How It Fits The Stack
Tributary sits above Brooks and below Domain Modeling.
What This Area Owns
- Event reducer abstractions and runtime composition
- Snapshot abstractions and storage-provider seams
- Runtime support for rebuilding derived state efficiently
What This Area Does Not Own
- Raw event-stream persistence
- Aggregate, saga, or projection business behavior
What This Page Guarantees
- It defines Tributary as the reducer and snapshot layer between raw streams and domain-facing behavior.
- It identifies the neighboring layers readers should switch to when the problem is actually stream persistence or domain behavior.
What This Page Does Not Claim
- Snapshot durability guarantees, rebuild guarantees, or retry behavior
- Full reducer catalog or operational guidance
- Detailed provider configuration or runtime failure documentation
Trade-Off To Keep In Mind
Tributary gives you an explicit reconstruction layer, but it is a supporting layer rather than the place where business behavior is authored.
Summary
Think of Tributary as the bridge between event streams and domain-facing behavior.