domain-modeling

Domain Modeling

Actively build and sharpen the project's domain model as you design. This is the active discipline — challenging terms, inventing edge-case scenarios, and writing the glossary and decisions down the moment they crystallise. Use it when you are changing the model, not just consuming it.

File structure

Most repos have a single context:

/
├── CONTEXT.md
├── docs/
│   └── adr/
│       ├── 0001-event-sourced-orders.md
│       └── 0002-postgres-for-write-model.md
└── src/

If a CONTEXT-MAP.md exists at the root, the repo has multiple bounded contexts, and the map points to where each one lives:

/
├── CONTEXT-MAP.md
├── docs/adr/                         ← system-wide decisions
├── src/
│   ├── ordering/
│   │   ├── CONTEXT.md
│   │   └── docs/adr/                 ← context-specific decisions
│   └── billing/
│       ├── CONTEXT.md
│       └── docs/adr/

Create files lazily — only when you have something to write. No CONTEXT.md yet? Create it when the first term resolves. No docs/adr/? Create it when the first ADR is warranted.

During the session

Challenge against the glossary

When the user uses a term that conflicts with the language already in CONTEXT.md, call it out immediately. "Your glossary defines 'cancellation' as X, but you seem to mean Y — which is it?"

Sharpen fuzzy language

When the user uses a vague or overloaded term, propose a precise canonical one. "You said 'account' — do you mean the Customer or the User? Those are different things."

Stress-test with concrete scenarios

When domain relationships are on the table, invent specific scenarios that probe the edges and force precision about where one concept ends and the next begins.

Cross-reference with the code

When the user states how something works, check whether the code agrees. On a contradiction, surface it: "Your code cancels whole Orders, but you just said partial cancellation is possible — which is right?"

Update CONTEXT.md inline