vcontainer

VContainer — Dependency Injection for Unity

VContainer is a lightweight, fast DI framework for Unity by hadashiA. It provides constructor injection for plain C# classes, method injection for MonoBehaviours, hierarchical scoping, and lifecycle management without the complexity of Zenject.

Why Dependency Injection in Unity

• Decouple systems: Components depend on interfaces, not concrete types
• Testability: Swap real implementations for mocks in tests
• No singletons: Avoid static state and its hidden coupling
• Configurable composition: Change wiring without changing code
• Explicit dependencies: Constructor parameters document what a class needs

LifetimeScope Hierarchy

VContainer uses LifetimeScope MonoBehaviours as composition roots. They form a parent-child hierarchy for dependency resolution.

RootLifetimeScope (DontDestroyOnLoad)
  |- AudioService (Singleton)
  |- SaveSystem (Singleton)
  |- AnalyticsService (Singleton)
  +- ISettingsProvider (Singleton)
      |
      |- MainMenuLifetimeScope (MainMenu scene)
      |     |- MainMenuController
      |     +- LeaderboardService
      |
      +- GameLifetimeScope (Game scene)
            |- GameManager
            |- SpawnSystem
            +- ScoreSystem

Root Scope (Project-Wide Services)

using VContainer;
using VContainer.Unity;

public class RootLifetimeScope : LifetimeScope
{
    [SerializeField] private AudioSettings _audioSettings;

    protected override void Configure(IContainerBuilder builder)
    {
        // Singletons survive scene loads
        builder.Register<AudioService>(Lifetime.Singleton).As<IAudioService>();
        builder.Register<SaveSystem>(Lifetime.Singleton).As<ISaveSystem>();
        builder.Register<AnalyticsService>(Lifetime.Singleton).As<IAnalyticsService>();

        // ScriptableObject instance
        builder.RegisterInstance(_audioSettings);
    }
}

Scene Scope (Scene-Specific)

public class GameLifetimeScope : LifetimeScope
{
    [SerializeField] private LevelConfig _levelConfig;

    protected override void Configure(IContainerBuilder builder)
    {
        // Scene-specific registrations
        builder.Register<ScoreSystem>(Lifetime.Scoped);
        builder.Register<WaveSpawner>(Lifetime.Scoped);

        // Entry point with lifecycle
        builder.RegisterEntryPoint<GameFlowController>();

        // MonoBehaviour already in scene hierarchy
        builder.RegisterComponentInHierarchy<PlayerController>();
        builder.RegisterComponentInHierarchy<HUDManager>();

        // Config data
        builder.RegisterInstance(_levelConfig);
    }
}