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CLAUDE.md

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+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Development Commands
+
+### Testing
+- Run all tests: `vendor/bin/phpunit`
+- Run tests with Docker: `docker-compose run --rm -w /tmp/ganesha -u ganesha client vendor/bin/phpunit`
+- Install dependencies with Docker: `docker-compose run --rm -w /tmp/ganesha -u ganesha client composer install`
+
+### Code Quality
+- Run static analysis: `vendor/bin/psalm`
+- PHP-CS-Fixer for code formatting: `vendor/bin/php-cs-fixer fix`
+
+### Local Development with Docker
+- Start data stores (Redis, Memcached, etc): `docker-compose up`
+- The Docker setup provides isolated environments for testing against different storage adapters
+
+## Architecture Overview
+
+### Core Circuit Breaker Pattern
+Ganesha is a PHP implementation of the Circuit Breaker pattern with a clean separation of concerns:
+
+- **Main Entry Point**: `Ganesha` class provides the core API (`isAvailable()`, `success()`, `failure()`)
+- **Builder Pattern**: Fluent builders for different strategies via `Builder::withRateStrategy()` and `Builder::withCountStrategy()`
+- **Strategy Pattern**: Two failure detection strategies (`Rate` and `Count`) implement `StrategyInterface`
+- **Storage Adapters**: Multiple adapters (Redis, Memcached, APCu, MongoDB) implement `AdapterInterface`
+
+### Two Circuit Breaker Strategies
+
+#### Rate Strategy
+Tracks failure rate percentage over a time window:
+- `timeWindow()` - Time period for evaluation
+- `failureRateThreshold()` - Percentage threshold (1-100)
+- `minimumRequests()` - Minimum requests before triggering
+- `intervalToHalfOpen()` - Time before retrying
+
+#### Count Strategy  
+Tracks absolute failure count:
+- `failureCountThreshold()` - Number of failures before triggering
+- `intervalToHalfOpen()` - Time before retrying
+
+### Storage Architecture
+Two time window implementations based on storage capabilities:
+- **SlidingTimeWindow** (Redis, MongoDB) - Rolling window of exact time periods
+- **TumblingTimeWindow** (APCu, Memcached) - Fixed time segments
+
+### HTTP Client Integrations
+- **Guzzle Middleware**: `GuzzleMiddleware` for transparent Guzzle integration
+- **Symfony HttpClient**: `GaneshaHttpClient` wrapper for Symfony HttpClient
+- Service name extraction strategies and failure detection customization
+
+### Key Components
+- `Configuration` - Validates and stores strategy parameters
+- `Context` - Manages circuit state and transitions
+- `Storage` - Abstraction layer over different storage adapters
+- `StorageKeys` - Configurable key naming for storage operations
+
+### Events System
+The circuit breaker publishes events:
+- `EVENT_TRIPPED` - Circuit opened due to failures
+- `EVENT_CALMED_DOWN` - Circuit closed after recovery
+- `EVENT_STORAGE_ERROR` - Storage backend issues
+
+## Testing Patterns
+
+Tests are organized by component with extensive integration testing for storage adapters. VCR (Video Cassette Recorder) is used for HTTP interaction recording in Guzzle middleware tests.
+
+The test structure mirrors the source structure under `tests/Ackintosh/` with comprehensive coverage of both strategies and all storage adapters.