tomevault-io Bounded Context Mapper — TypeScript DDD
Produce a structured domain map that gives the team a shared understanding of where responsibilities live, how contexts relate, and what language each context owns.
Process (follow in order)
1. Extract domain concepts
From the user's description, identify and list:
- Nouns → candidate Entities and Value Objects
- Verbs → candidate Domain Events and Commands
- Business rules → candidate invariants for Aggregates
2. Group into bounded contexts
Cluster concepts that share a ubiquitous language and a clear owner. Each bounded context should:
- Have a single team or module owning it
- Have a name that domain experts recognize
- Be cohesive — the language inside it doesn't leak to other contexts
3. Define relationships
For each pair of interacting contexts, name the relationship pattern:
| Pattern | When to use |
|---|---|
| Shared Kernel | Two contexts share a small, stable subset of the model |
| Customer/Supplier | One context consumes another's output; upstream is the supplier |
| Conformist | Downstream adapts entirely to upstream's model |
| Anti-Corruption Layer (ACL) | Downstream translates upstream's model to protect its own language |
| Open Host Service | Upstream publishes a stable, versioned API for many consumers |
| Published Language | Shared data format (e.g. events on a bus) both sides agree on |
| Partnership | Two contexts evolve together with joint planning |
| Separate Ways | No integration — contexts are fully independent |
4. Identify aggregates per context
For each context, name:
- The Aggregate Root (the entity that owns the transaction boundary)
- Its children (entities and value objects inside the boundary)
- The domain events it emits
5. Define ubiquitous language
For each context, list the key terms with one-line definitions. If the same word means different things in different contexts (e.g. "Order" in Billing vs. Shipping), call it out explicitly — this is a linguistic boundary.
Output format
# Domain Map: [System / Feature Name]
## Bounded Contexts
### [ContextName]
**Responsibility:** [one sentence]
**Owner:** [team or module name]
**Aggregate Roots:**
- `[AggregateName]` — [one-line responsibility]
- Children: `[Entity]`, `[ValueObject]`
- Emits: `[DomainEventName]`, ...
**Ubiquitous Language:**
| Term | Definition |
|------|-----------|
| [Term] | [Definition as understood inside this context only] |
---
### [AnotherContextName]
...
---
## Context Map
```
[ContextA] --[ACL]--> [ContextB]
[ContextB] --[Customer/Supplier]--> [ContextC]
[ContextA] --[Shared Kernel]--> [ContextD]
```
### Relationship details
- **[ContextA] → [ContextB]** (ACL): [ContextB] translates [ContextA]'s `Order` into its own `Purchase` to avoid coupling.
- **[ContextB] → [ContextC]** (Customer/Supplier): [ContextB] publishes `OrderShippedEvent`; [ContextC] subscribes.
---
## Linguistic boundaries
List any terms that appear in multiple contexts with *different meanings*. These are red flags for accidental coupling.
| Term | [ContextA] meaning | [ContextB] meaning |
|------|-------------------|-------------------|
| Order | Customer's purchase intent | Warehouse pick-list |
---
## Domain events flow
```
[AggregateA] --emits--> [DomainEventX] --consumed by--> [ContextB handler]
```
---
## Open questions
- [ ] [Unresolved design decision or missing domain knowledge]
TypeScript folder structure (suggest this after mapping)
src/
[context-name]/ ← one folder per bounded context
domain/
[AggregateName].ts ← aggregate root
[ValueObject].ts
events/
[DomainEventName].ts
repositories/
I[AggregateName]Repository.ts ← interface only
application/
use-cases/
[ActionName]UseCase.ts
dtos/
infrastructure/
persistence/
[AggregateName]Repository.ts ← implementation
Quality checks
Before finishing the map, verify:
- Every aggregate root has at least one domain event
- No entity is shared between two contexts without a Shared Kernel or ACL
- Every relationship has a named pattern
- Linguistic boundaries are documented
- The map answers: "who owns the data?" for every core entity
Source: Methasit-Pun/ts-ddd-clean-architecture — distributed by TomeVault.