Dependency Injection

GoForj uses explicit Go constructors and Wire-generated code. It does not use a runtime service locator.

Each app has its own Wire graph.

The Model

Application packages own constructors:

func NewService(repo *Repository) *Service {
	return &Service{repo: repo}
}

The app's Wire package assembles those constructors:

internal package -> app/wire provider set -> app/wire/wire_gen.go -> app

For a named app, the graph lives under app/<name>/wire.

Where It Lives

Default app:

app/wire/
  wire.go
  wire_gen.go
  inject_cmd_app.go
  inject_http_controllers_app.go
  inject_services_app.go

Named app:

app/marketplace/wire/
  wire.go
  wire_gen.go
  inject_cmd_app.go
  inject_http_controllers_app.go
  inject_services_app.go

Generated files appear only when the selected components need them.

Provider Sets

Provider sets group constructors for a specific app surface:

• application services
• repositories
• HTTP controllers
• commands
• jobs
• schedules
• subscribers
• framework managers

The order inside wire.NewSet is not construction order. Wire reads the whole graph, matches types, and writes ordinary Go code to wire_gen.go.

Construction Boundary

Wire constructs the app. It does not start long-running runtime work.

Construction can allocate services, adapters, managers, controllers, commands, and registries. HTTP servers, queue workers, and schedulers start when a command starts that runtime.

Regenerate Wiring

Run the build pipeline after changing providers, generated components, or Wire sets:

forj build

For a named app:

forj marketplace build

Dev Loop

forj dev normally runs the build path through each App lifecycle listed under dev.apps. In a multi-app Project, unqualified forj dev manages every listed App.

Common Mistakes

Common mistakes

• Do not use package globals to hide dependencies from Wire.
• Do not edit wire_gen.go by hand.
• Do not add nil guards around required constructor-injected dependencies.
• Do not put business workflows in provider functions.

Next Steps

• Providers defines provider functions.
• Wiring Recipes shows which app-local file to edit.
• Reading Wire Errors explains common Wire failures.