v2.5.0: lifecycle failure handling

What's changed

• Define lifecycle failure boundaries: empty Run now panics, and component errors include component names while preserving errors.Is.
• Add configurable shutdown timeouts through WithShutdownTimeout and ErrShutdownTimeout.
• Preserve and join independent input, readiness, component, cleanup, and timeout errors without propagated cancellation noise or duplicate causes.
• Distinguish successful probe(nil) from readiness failures wrapping context.Canceled.
• Release lifecycle listeners and signal handlers, and simplify parent-readiness coordination.

Pull requests

• #13
• #14

Release v2.3.0: add dependency graph export in DOT format

- Add WithGraphOutput() option to auto-save graph on lifecycle start
- Add BuildGraph() method to Lifecycle interface
- Add Graph.ToDOT() method to convert graph to Graphviz DOT format
- Add /graph/dot API endpoint in example app
- Add "Download DOT" button to example web UI
- Update README with graph export documentation

Graph can be visualized using Graphviz tools:
  dot -Tpng graph.dot -o graph.png

Release v2.2.0: Add fluent API and simplified lifecycle management Latest

• Add Register() helper function for fluent component registration
• Add Run() helper function for simplified lifecycle execution
• Enhance lifecycle management with improved error handling
• Add comprehensive test coverage for new functionality
• Update example application with new API usage
• Improve component dependency management and startup order
• Add support for graceful shutdown hooks with WithShutdownHook()
• Enhance lifecycle status transitions and error propagation

BREAKING CHANGES:

• Lifecycle.Run() method signature changed:
• OLD: Run(ctx context.Context, readinessProbe func(err error)) func() error
• NEW: Run(ctx context.Context, readinessProbe func(err error)) error
• Lifecycle is now a Component without casting
• Added blocking Run() helper method with callback support
• Lifecycle no longer shuts down on signals by default (use WithShutdownHook() option)

Migration guide:

• Replace: waitFn := lc.Run(ctx, probe); err := waitFn()
• With: err := lc.Run(ctx, probe)
• Use goscade.Run() helper for blocking execution with callback
• Add WithShutdownHook() option if signal handling is needed

Release v1.2.0: explicit dependency support to Register method

• Add implicitDeps parameter to Register method signature
• Support explicit dependency declaration when automatic detection is insufficient

Release v1.1.0: performance boost & API improvements

🎯 Major Performance Optimization

• BFS Algorithm: Replaced recursive dependency detection with breadth-first search using queues
• Memory Efficiency: Optimized component graph traversal for better performance with large component trees
• Faster Startup: Reduced overhead in dependency resolution phase

🔧 New Adapter Pattern

• Component Wrapping: Wrap existing components with custom logic using NewAdapter()
• Custom Startup Logic: Add readiness probes and custom initialization without modifying original components
• Delegate Naming: Automatic component naming for better logging and debugging

🧪 Enhanced Testing Suite

• 45 Test Cases: Comprehensive coverage including adapter pattern, timeouts, and nested lifecycles
• Race Condition Free: All tests pass with -race flag and multiple iterations
• Timeout Testing: Configurable startup timeouts with proper error handling
• Nested Lifecycle Tests: Verify lifecycle-as-component functionality

🗑️ Simplified Architecture

• Removed Metrics System: Eliminated complex metrics collection (107 lines removed)
• Cleaner API: Focused on core lifecycle management without observability overhead
• Reduced Dependencies: Simpler codebase with fewer moving parts

🔄 API Consistency

• Queue Methods: Standardized Push()/Pop() instead of Enqueue()/Dequeue()
• Nested Lifecycles: AsComponent() method for lifecycle composition
• Fluent Registration: Register() helper for chaining component creation

📚 Documentation Overhaul

• Classic README Structure: Moved examples to dedicated "Advanced Usage" section
• Practical Examples: Real-world usage patterns with adapter pattern
• Clear API Reference: Comprehensive documentation for all public methods

⚡ Performance Metrics

• 98.7% Test Coverage: Maintained high code coverage
• Zero Race Conditions: Verified concurrent safety
• Optimized Graph Traversal: BFS algorithm for dependency detection
• Memory Efficient: Reduced allocation overhead in component startup

---

Breaking Changes: Queue method names changed (Enqueue/Dequeue → Push/Pop)
Migration: Update queue usage in existing code
Compatibility: Full backward compatibility for core lifecycle functionality

Release v1.0.0: adapter pattern, fluent API, configurable timeouts

• Add Adapter Pattern for component wrapping
• Add Queue utilities (FIFO/LIFO)
• Add Fluent Registration API
• Add configurable startup timeouts
• Add circular dependency support
• Improve test coverage to 98.7%
• Add comprehensive documentation
• Update README with examples
• All tests pass with race detection

Release v0.2.0: simplified startup, parallel dependency resolution

What's new in v0.2.0:

• Removed runner/context setup from users
• Added internal graceful shutdown logic via signal handling
• Dependencies now resolved in parallel for faster startup
• RunAllComponents returns shutdown wait func
• Refactored tests, removed errgroup from public API
• Simplified examples

This version is backward-incompatible due to changes in RunAllComponents.

🚀 First Release: goscade v0.1.0

Initial release of goscade — a lightweight Go library for coordinating component lifecycle with dependency-aware startup and shutdown.

✅ Features:

• Declarative dependency graph via component registration
• Automatic topological sort and run-order resolution
• Controlled startup and shutdown with cancellation
• Real-time status tracking for each component

📦 Example:

• Web UI for visualizing the dependency graph and interacting with components
• Simulated delays and failure injection for testing

🔗 Resources:

• Medium article