CompanyGraph — Domain-driven design, as pages you can check

A bounded context, its language, its aggregates and events, as pages a check holds to their boundary.

rests onconcept Pack

Robert Blust · Software Engineer & Architect

The method you know

The pack writes the words of domain-driven design down as pages, rather than inventing its own.

rests onconcept Pack

Bounded context

The boundary within which one model and one language hold, as a page: what it is responsible for, how it is classified and the domain it realizes.

rests onbounded-context Resolution

model/bounded-contexts/resolution/resolution.md

---
id: 01a0faaa-5d02-71db-bcdb-f672c4324bee
source: Local
classification: core
realizes:
  - Core
decisions:
  - A reference resolves by its declared type, never by name alone
---
# Resolution
> Turns the names a page writes into the edges of the graph, by the type each schema declares and the owner a row names. Whether a page has the shape its schema asks for is left to the checks.
## Responsibilities
- Find the entity a written name means, looking only among the type the schema declares for that field or column
- Look for an owned entity only inside the owner its row names, so two owners can each have a page of the same name
…

Its language

Concept designs: the terms of the context's language, each an entity or a value object, owned by its context.

rests onconcept-design Entity concept-design Edge concept-design Scope concept-design Declaration concept-design Graph

model/bounded-contexts/resolution/concept-designs/

declaration.md   kind: value object
edge.md          kind: value object
entity.md        kind: value object
graph.md         kind: entity
scope.md         kind: value object

Aggregate and event

An aggregate keeps a cluster of concept designs consistent as one unit. A domain event is a type, because other contexts name it; a command is a row, because nothing outside its aggregate does.

rests onaggregate Graph domain-event Graph drawn

model/bounded-contexts/resolution/aggregates/graph.md

---
…
root: Graph
members:
  - Edge
  - Scope
…
# Graph
…
## Invariants
| Label | Invariant |
| --- | --- |
| INV-R1 | Every edge runs between two entities of the graph; a name that resolves to nothing stops the read, and no edge points nowhere. |
…
## Handled commands
| Command | Emits | When | Description |
| --- | --- | --- | --- |
| Read an instance | | | Reads every page against the schemas the instance vendors and draws the graph, or refuses at the first name that resolves to nothing |
…

Context map

A relationship between contexts is a row on the context that depends; a symmetric one is written once, on either side.

rests onbounded-context Checking

model/bounded-contexts/checking/checking.md

…
## Relationships
| Context | Pattern |
| --- | --- |
| Resolution | conformist |
| Vendoring | shared kernel |
…

Feature design

How a feature is built across the contexts it touches: an operational principle, then scenarios in Gherkin.

rests onfeature-design A name that names nothing is reported where it is written

model/feature-designs/a-name-that-names-nothing-is-reported-where-it-is-written.md

---
id: 01a10031-6925-7b3c-8f04-87b19b4f6103
source: Local
refines: Checks an instance runs
contexts:
  - Resolution
…
# A name that names nothing is reported where it is written
…
## Operational principle
When a page names an entity that does not exist under the type its field declares, the check fails on that page and says which type it searched, before the change can land.
## Scenarios
### SC-C1: A name that exists nowhere
…

Where it departs

Where the pack does not do what its sources do, its README says so.

rests ondecision A reference resolves by its declared type, never by name alone

Strategic classificationon the bounded context, as the Bounded Context Canvas puts it, not on Evans's subdomain, so core's domain stays untouched
A domain event and a commandan event a type, because other contexts name it; a command a row, because nothing outside its aggregate does
An architecture decisioncore's decision, which already has an ADR's sections; the pack's types name it
A value's typeTerm for a term of the context, a reference; Type for a plain type, which names nothing

How it joins core

The pack joins core's types: a bounded context realizes a domain, a concept design refines a concept and a feature design refines a feature. Every edge runs one way and is optional.

rests ondomain Core feature Checks an instance runs

LEVEL 1 · SOFTWAREbounded context · concept design · feature design

↓ realizes · refines · refines ↓

LEVEL 0Coredomain · concept · feature

What the check holds

A name is looked for only within its type and, for an owned type, its owner. One that names nothing fails where it is written.

rests onconcept-design Entity · Publishing concept-design Entity · Resolution concept-design Entity · Serving concept Check

$ companygraph check
✗ 1 problem in model/ against meta/core, meta/software, meta/organization, meta/landscape/ at core 0.65.0
  model/bounded-contexts/resolution/concept-designs/edge.md: `Concept` in "## Relations" is declared `ref → concept-design` and says "Declarations", which names no entity in model/; a declared reference must resolve, and the concept-design it matches here is "Declaration" (R4)
  not checked: every `## Writing rules` in every schema — that is the agent pass, R0
✓ 378 Markdown files in the one form

Left for later

What the pack does not have yet is named in its README, not hidden.

laterservices, repositories, factories and modules
laterC4's system, container and component
latera type for a relationship between contexts
latercommands as a type
latera subdomain type
latera level field
laterread models and policies as types, from Event Modeling

rests onconcept Pack

Drawn by the server

Nobody drew these. The MCP server's own code draws them from the pages, at the commit the site pins.

rests onbounded-context Checking bounded-context Resolution bounded-context Procedures bounded-context Vendoring aggregate Check run

mcp.companygraph.io

Checking

CompanyGraph — Domain-driven design, as pages you can check

The method you know

Bounded context

Its language

Aggregate and event

Context map

Feature design

Where it departs

How it joins core

What the check holds

Left for later

Drawn by the server

Your language, held to its boundary

Sprecher-Notiz