Koin Playground Apps

Production-quality reference applications demonstrating Koin dependency injection with the Koin Compiler Plugin.

Two identical multi-module Android apps — one using Annotations, one using the Safe DSL — so you can compare approaches side by side.

Apps

App	DI Approach	Key Patterns
app-annotations/	@Singleton, @Module, @ComponentScan, @Configuration, @KoinApplication	Annotation-driven with auto-discovery
app-dsl/	single<T>(), factory<T>(), viewModel<T>(), create(::fn), bind	DSL with explicit module composition

Both use the Koin Compiler Plugin for compile-time dependency validation.

Architecture

Inspired by Now in Android — multi-module, offline-first, Compose UI.

app-*/
├── app/                    # Application + main ViewModels
├── core/
│   ├── common/             # Dispatchers, custom qualifiers
│   ├── model/              # Domain models
│   ├── database/           # Room database
│   ├── datastore/          # DataStore preferences
│   ├── network/            # HTTP client
│   ├── data/               # Repositories
│   ├── domain/             # Use cases
│   ├── analytics/          # Analytics
│   └── notifications/      # Notifications
├── feature/
│   ├── home/               # Home screen
│   ├── bookmarks/          # Bookmarks
│   ├── settings/           # Settings
│   └── detail/             # Detail (with nav args)
└── sync/
    └── work/               # WorkManager sync

Stack

• Koin 4.2 + Compiler Plugin 0.4.1
• Kotlin 2.3.20 (K2)
• Jetpack Compose
• Room, DataStore, WorkManager
• Coroutines + Flow
• Navigation Compose

Running

# Annotations app
cd app-annotations
./gradlew :app:installDebug

# DSL app
cd app-dsl
./gradlew :app:installDebug

Key Patterns Covered

• Application bootstrap (startKoin<T> / startKoin { })
• Module composition with includes() / @Module(includes = [...])
• Custom qualifier annotations (@Dispatcher with enum)
• Interface binding (bind / automatic)
• ViewModel with SavedStateHandle and @InjectedParam
• WorkManager integration (@KoinWorker / worker<T>())
• Activity scopes (AndroidScopeComponent)
• Compose ViewModel injection (koinViewModel())
• External library wrapping (Room, Retrofit patterns)

Documentation

• Koin Documentation
• Compile-Time Safety
• Compiler Plugin Setup

License

Apache 2.0