dependency-injection-architecture

Set up dependency injection in Kotlin by defining explicit module wiring for presentation, domain, data, and common layers using Koin or Spring. This enforces constructor injection and interface-based bindings to create testable dependency graphs while preventing cross-layer architectural drift.

Organize Koin modules using profile-based module selection to separate dev and prod environments. Bind repository and service interfaces to specific implementations per profile, applying singleton scope for expensive resources and factory scope for stateless objects.

Replace in-memory repositories by defining interface-based contracts in the domain layer and binding database-backed implementations in the data layer modules. This clean architecture wiring allows swapping repository implementations without modifying presentation or domain layer logic.

Yes, this dependency injection approach provides idiomatic patterns for both Koin and Spring in Kotlin. It recommends module organization, profile-based selection, and constructor injection rules that apply seamlessly whether you choose Koin's DSL or Spring's annotation-based bean configuration.

Prohibit cross-layer SDK or DB imports in domain layers to prevent architectural drift and maintain testability. Defining allowed dependency directions between presentation, domain, data, and common layers ensures that core business logic remains decoupled from external infrastructure frameworks.

Use singleton scope for expensive shared resources like database connections, and factory scope for stateless transient objects. Applying these dependency injection scopes correctly in Koin or Spring modules optimizes resource management and prevents unintended state sharing across requests.