business-logic

To enforce business logic, you extract domain rules and codify them as explicit guards within the service layer. This centralizes constraints at the hinge points of operations, ensuring correct behavior before processing multi-step workflows.

Managing state transitions for domain rules is best handled using a state machine pattern. This restricts transitions to allowed paths, such as Draft to Submitted to Approved, preventing invalid states and ensuring workflow integrity.

Domain events decouple side effects in business logic by separating notifications like emails and analytics from core operations. This allows the service layer to trigger an event without directly managing the downstream webhook or processing logic.

Write unit tests for business logic by mapping clear rule-driven tests to each domain requirement. Validate explicit guards, state transitions, and pure calculation functions independently to ensure comprehensive coverage of expected behavior.

You do not need a specific framework to implement domain rules or state machines. The approach uses explicit guards, pure calculation functions, and domain events within your existing service layer, making it framework-agnostic and highly testable.