Event Flow Map

The event flow map shows how domain events flow between services — who publishes, who consumes, and the events in between.

How it works

The event flow map is driven by models/event-mapping.yaml, which bridges registry types to semantic event-flow roles:

service_type: software_subsystem     # what acts as a "service"
event_type: domain_event             # what acts as an "event"
publishes_field: published_by_api_endpoints
consumes_field: consumed_by_api_endpoints

The loader follows these paths at build time:

1. Find all domain events in the domain
2. Follow published_by_api_endpoints to discover publishers
3. Follow consumed_by_api_endpoints to discover consumers
4. Auto-traverse intermediate hops (event -> API endpoint -> subsystem) via BFS

Layout

The graph is arranged left-to-right in three columns:

Publishers  ->  Events  ->  Consumers
(services)      (domain      (services)
                 events)

Cross-domain services (consuming events from another domain) are visually marked.

Visual features

Feature	Description
Animated edges	Flowing dots along publish/consume edges show data flow direction
Color coding	Blue edges for “publishes”, green edges for “consumes”
Edge labels	Each edge shows “PUBLISHES” or “CONSUMES” in a styled badge
Cross-domain flag	Services from other domains get a special indicator
PNG export	Download the graph as an image

Legend

The bottom-right legend shows:

• Publish and consume edge styles
• Event node appearance
• Service node appearance

Adding events

To populate the event flow map, create domain event Markdown files with publish/consume connections:

---
type: domain-event
name: Order Placed
domain: Order Management
status: active
event_format: CloudEvents/JSON

published_by_api_endpoints:
  - order-create-endpoint
consumed_by_api_endpoints:
  - billing-invoice-trigger
  - analytics-event-ingest
---

The more connections your events have, the richer the event flow visualization becomes. Cross-domain consumers make the graph particularly interesting.