Event-Driven Architecture: How We Decoupled Our Monolith

When TrueValue started, everything was in one Django application. As we added modules — Marketing, Payroll, Appointments — the coupling became painful. An event-driven architecture let us decouple without microservices.

How It Works

Each module publishes domain events (deal.closed, contact.created, invoice.paid) to a central event bus. Other modules subscribe to events they care about and react independently.

Benefits

• Modules can be developed and deployed independently
• New integrations require zero changes to the publishing module
• Events create a natural audit trail
• Failed handlers can retry without affecting the source operation
• Testing is simpler — publish an event and verify the reaction

“Events are facts about what happened. They do not prescribe what should happen next — that is the subscriber's decision.”