Composable Architecture

What it does

This skill, Composable Architecture (TCA), provides a structured architecture for building complex and testable application features. It emphasizes predictable state evolution through composable reducers, centralized state management, and clear side effect handling. TCA promotes reusability by organizing applications into smaller, manageable components with well-defined dependencies, ultimately accelerating development workflows and improving maintainability.

When to use it

• Developing complex user interfaces requiring robust state management.
• Building features that need to be highly testable and predictable.
• Creating reusable UI components across different parts of an application.
• Implementing navigation flows with deep linking or recursive structures.
• Sharing state between distinct, composable features within the app.

Key capabilities

• Composable Reducers: Building features from smaller, reusable reducers.
• Centralized State Management: Managing application state in a predictable and organized manner.
• Side Effect Handling: Controlling asynchronous operations and external interactions.
• Navigation Stack: Implementing navigation flows with pushing, popping, and programmatic dismissal.
• Shared State: Sharing data between different features using mechanisms like @Shared and .appStorage.
• Dependency Management: Defining and managing dependencies between components using @DependencyClient and @Dependency.
• Testing Support: Providing tools and patterns for comprehensive unit testing, including TestStore, TestClock, and exhaustivity checking.

Example prompts

• "Show me how to create a reducer with @Reducer, State, Action, and @ViewAction."
• "How do I implement navigation using NavigationStack?"
• "Explain how to share state between features using @Shared."
• “Demonstrate setting up test dependencies for a feature.”

Tips & gotchas

• Reference Files: Always load reference files when working with TCA, even if you think they might not be needed. This ensures access to necessary patterns and avoids potential errors.
• Avoid Over-Modularization: Breaking features into too many small reducers can complicate state management; keep related logic together unless there’s a clear need for reuse.
• Effect Lifecycles: Properly manage the lifecycles of effects, ensuring cancellation to prevent stale data or duplicate requests.