# Modelling - [Introduction](https://docs.ecotone.tech/modelling/message-driven-php-introduction.md): Message Driven System with Domain Driven Design principles in PHP - [Message Bus and CQRS](https://docs.ecotone.tech/modelling/command-handling.md): PHP Message Bus, CQRS, Command Event Query Handlers - [CQRS Introduction - Commands](https://docs.ecotone.tech/modelling/command-handling/external-command-handlers.md): Commands CQRS PHP - [Query Handling](https://docs.ecotone.tech/modelling/command-handling/external-command-handlers/query-handling.md): Query CQRS PHP - [Event Handling](https://docs.ecotone.tech/modelling/command-handling/external-command-handlers/event-handling.md): Event CQRS PHP - [Aggregate Introduction](https://docs.ecotone.tech/modelling/command-handling/state-stored-aggregate.md): DDD Aggregates PHP - [Aggregate Command Handlers](https://docs.ecotone.tech/modelling/command-handling/state-stored-aggregate/aggregate-command-handlers.md): DDD PHP - [Aggregate Query Handlers](https://docs.ecotone.tech/modelling/command-handling/state-stored-aggregate/aggregate-query-handlers.md): DDD PHP - [Aggregate Event Handlers](https://docs.ecotone.tech/modelling/command-handling/state-stored-aggregate/aggregate-event-handlers.md): DDD PHP - [Advanced Aggregate creation](https://docs.ecotone.tech/modelling/command-handling/state-stored-aggregate/advanced-aggregate-creation.md): DDD PHP - [Repositories Introduction](https://docs.ecotone.tech/modelling/command-handling/repository.md): Repository PHP - [Configure Repository](https://docs.ecotone.tech/modelling/command-handling/repository/configure-repository.md): Configuring custom Aggregate repositories in Ecotone PHP - [Fetching/Storing Aggregates](https://docs.ecotone.tech/modelling/command-handling/repository/repository.md): Fetching and storing Aggregates with repositories in Ecotone PHP - [Inbuilt Repositories](https://docs.ecotone.tech/modelling/command-handling/repository/inbuilt-repositories.md): Built-in Aggregate repositories for Doctrine ORM, Eloquent, and DBAL - [Business Interface](https://docs.ecotone.tech/modelling/command-handling/business-interface.md): Business Interfaces for type-safe messaging in Ecotone PHP - [Introduction](https://docs.ecotone.tech/modelling/command-handling/business-interface/introduction.md): Introduction to Business Interfaces in Ecotone PHP - [Database Business Interface](https://docs.ecotone.tech/modelling/command-handling/business-interface/working-with-database.md): Database Business Interface for type-safe database access in PHP - [Converting Parameters](https://docs.ecotone.tech/modelling/command-handling/business-interface/working-with-database/converting-parameters.md): Converting parameters in Database Business Interface queries - [Converting Results](https://docs.ecotone.tech/modelling/command-handling/business-interface/working-with-database/converting-results.md): Converting query results in Database Business Interface - [Saga Introduction](https://docs.ecotone.tech/modelling/command-handling/saga.md): Process Manager Saga PHP - [Identifier Mapping](https://docs.ecotone.tech/modelling/command-handling/identifier-mapping.md): Mapping identifiers for Aggregate and Saga routing in Ecotone - [Extending Messaging (Middlewares)](https://docs.ecotone.tech/modelling/extending-messaging-middlewares.md): Extending messaging with Interceptors and Middlewares in Ecotone PHP - [Message Headers](https://docs.ecotone.tech/modelling/extending-messaging-middlewares/message-headers.md): Working with Message Headers and metadata in Ecotone PHP - [Interceptors (Middlewares)](https://docs.ecotone.tech/modelling/extending-messaging-middlewares/interceptors.md): PHP Interceptors Middlewares - [Additional Scenarios](https://docs.ecotone.tech/modelling/extending-messaging-middlewares/interceptors/additional-scenarios.md): Advanced Interceptor scenarios and configurations in Ecotone - [Intercepting Asynchronous Endpoints](https://docs.ecotone.tech/modelling/extending-messaging-middlewares/intercepting-asynchronous-endpoints.md): Intercepting asynchronous message endpoints in Ecotone PHP - [Extending Message Buses (Gateways)](https://docs.ecotone.tech/modelling/extending-messaging-middlewares/extending-message-buses-gateways.md): Extending Command, Event, and Query Buses with custom Gateways - [Event Sourcing](https://docs.ecotone.tech/modelling/event-sourcing.md): Event Sourcing PHP - [Installation](https://docs.ecotone.tech/modelling/event-sourcing/installation.md): Installing Event Sourcing support in Ecotone PHP - [Event Sourcing Introduction](https://docs.ecotone.tech/modelling/event-sourcing/event-sourcing-introduction.md): Using Event Sourcing in PHP - [Working with Event Streams](https://docs.ecotone.tech/modelling/event-sourcing/event-sourcing-introduction/working-with-event-streams.md): Working with Event Streams in Ecotone PHP - [Event Sourcing Aggregates](https://docs.ecotone.tech/modelling/event-sourcing/event-sourcing-introduction/event-sourcing-aggregates.md): Event Sourcing Aggregates in Ecotone PHP - [Working with Aggregates](https://docs.ecotone.tech/modelling/event-sourcing/event-sourcing-introduction/event-sourcing-aggregates/working-with-aggregates.md): Working with Event Sourcing Aggregates in Ecotone PHP - [Applying Events](https://docs.ecotone.tech/modelling/event-sourcing/event-sourcing-introduction/event-sourcing-aggregates/applying-events.md): Applying events to rebuild Event Sourcing Aggregate state in PHP - [Different ways to Record Events](https://docs.ecotone.tech/modelling/event-sourcing/event-sourcing-introduction/event-sourcing-aggregates/different-ways-to-record-events.md): Different ways to record events in Event Sourcing Aggregates - [Working with Metadata](https://docs.ecotone.tech/modelling/event-sourcing/event-sourcing-introduction/working-with-metadata.md): Working with event metadata in Event Sourcing - [Event versioning](https://docs.ecotone.tech/modelling/event-sourcing/event-sourcing-introduction/event-versioning.md): Event versioning and upcasting for Event Sourcing in PHP - [Event Stream Persistence](https://docs.ecotone.tech/modelling/event-sourcing/event-sourcing-introduction/persistence-strategy.md): PHP Event Sourcing Persistence Strategy - [Event Sourcing Repository](https://docs.ecotone.tech/modelling/event-sourcing/event-sourcing-introduction/persistence-strategy/event-sourcing-repository.md): Configuring Event Sourcing repositories in Ecotone PHP - [Making Stream immune to changes](https://docs.ecotone.tech/modelling/event-sourcing/event-sourcing-introduction/persistence-strategy/making-stream-immune-to-changes.md): Making event streams immune to class and namespace changes - [Snapshoting](https://docs.ecotone.tech/modelling/event-sourcing/event-sourcing-introduction/persistence-strategy/snapshoting.md): PHP Event Sourcing Snapshoting - [Persistence Strategies](https://docs.ecotone.tech/modelling/event-sourcing/event-sourcing-introduction/persistence-strategy/persistence-strategies.md): Event stream persistence strategies in Ecotone PHP - [Event Serialization and PII Data (GDPR)](https://docs.ecotone.tech/modelling/event-sourcing/event-sourcing-introduction/persistence-strategy/event-serialization-and-pii-data-gdpr.md): Event serialization and GDPR-compliant PII data handling - [Projection Introduction](https://docs.ecotone.tech/modelling/event-sourcing/setting-up-projections.md): PHP Event Sourcing Projections - [Event Streams and Handlers](https://docs.ecotone.tech/modelling/event-sourcing/setting-up-projections/event-streams-and-handlers.md): PHP Event Sourcing Projection Streams and Event Handlers - [Projections with Document Store](https://docs.ecotone.tech/modelling/event-sourcing/setting-up-projections/document-store-projection.md): PHP Event Sourcing Projections with Document Store - [Execution Modes](https://docs.ecotone.tech/modelling/event-sourcing/setting-up-projections/execution-modes.md): PHP Event Sourcing Projection Execution Modes - [Lifecycle Management](https://docs.ecotone.tech/modelling/event-sourcing/setting-up-projections/lifecycle-management.md): PHP Event Sourcing Projection Lifecycle and CLI - [Projections with State](https://docs.ecotone.tech/modelling/event-sourcing/setting-up-projections/projections-with-state.md): PHP Event Sourcing Stateful Projections - [Emitting Events](https://docs.ecotone.tech/modelling/event-sourcing/setting-up-projections/emitting-events.md): PHP Event Sourcing Projection Event Emission - [Backfill and Rebuild](https://docs.ecotone.tech/modelling/event-sourcing/setting-up-projections/backfill-and-rebuild.md): PHP Event Sourcing Projection Backfill and Rebuild - [Failure Handling](https://docs.ecotone.tech/modelling/event-sourcing/setting-up-projections/failure-handling.md): PHP Event Sourcing Projection Failure Handling and Recovery - [Scaling and Advanced](https://docs.ecotone.tech/modelling/event-sourcing/setting-up-projections/scaling-and-advanced.md): PHP Event Sourcing Projection Scaling - [Gap Detection and Consistency](https://docs.ecotone.tech/modelling/event-sourcing/setting-up-projections/gap-detection-and-consistency.md): PHP Event Sourcing Projection Gap Detection - [Blue-Green Deployments](https://docs.ecotone.tech/modelling/event-sourcing/setting-up-projections/blue-green-deployments.md): PHP Event Sourcing Projection Blue-Green Deployments - [Upgrading from V1 to V2](https://docs.ecotone.tech/modelling/event-sourcing/setting-up-projections/upgrading-from-v1.md): Upgrading from Projection V1 to ProjectionV2 - [Recovering, Tracing and Monitoring](https://docs.ecotone.tech/modelling/recovering-tracing-and-monitoring.md): Recovering, tracing, and monitoring message-driven applications - [Resiliency](https://docs.ecotone.tech/modelling/recovering-tracing-and-monitoring/resiliency.md): Production resilience with retries, dead letter, outbox, and deduplication - [Retries](https://docs.ecotone.tech/modelling/recovering-tracing-and-monitoring/resiliency/retries.md): Configuring automatic message retry strategies in Ecotone PHP - [Error Channel](https://docs.ecotone.tech/modelling/recovering-tracing-and-monitoring/resiliency/error-channel-and-dead-letter.md): Error channels and dead letter queues for failed message handling - [Dbal Dead Letter](https://docs.ecotone.tech/modelling/recovering-tracing-and-monitoring/resiliency/error-channel-and-dead-letter/dbal-dead-letter.md): DBAL-based dead letter queue for storing and replaying failed messages - [Final Failure Strategy](https://docs.ecotone.tech/modelling/recovering-tracing-and-monitoring/resiliency/final-failure-strategy.md): Final failure strategy when all message retries are exhausted - [Idempotency (Deduplication)](https://docs.ecotone.tech/modelling/recovering-tracing-and-monitoring/resiliency/idempotent-consumer-deduplication.md): Idempotent consumer pattern for message deduplication in PHP - [Resilient Sending](https://docs.ecotone.tech/modelling/recovering-tracing-and-monitoring/resiliency/resilient-sending.md): Resilient sending for guaranteed message delivery to async channels - [Outbox Pattern](https://docs.ecotone.tech/modelling/recovering-tracing-and-monitoring/resiliency/outbox-pattern.md): Outbox pattern for atomic message publishing with database transactions - [Concurrency Handling](https://docs.ecotone.tech/modelling/recovering-tracing-and-monitoring/resiliency/concurrency-handling.md): Handling concurrency with optimistic and pessimistic locking - [Message Handling Isolation](https://docs.ecotone.tech/modelling/recovering-tracing-and-monitoring/message-handling-isolation.md): Message handling isolation for safe retries without side effects - [Ecotone Pulse (Service Dashboard)](https://docs.ecotone.tech/modelling/recovering-tracing-and-monitoring/ecotone-pulse-service-dashboard.md): Ecotone Pulse service dashboard for monitoring message consumers - [Asynchronous Handling and Scheduling](https://docs.ecotone.tech/modelling/asynchronous-handling.md): Asynchronous PHP - [Asynchronous Message Handlers](https://docs.ecotone.tech/modelling/asynchronous-handling/asynchronous-message-handlers.md): Making message handlers asynchronous with a single attribute - [Asynchronous Message Bus (Gateways)](https://docs.ecotone.tech/modelling/asynchronous-handling/asynchronous-message-bus-gateways.md): Asynchronous Message Bus Gateways for channel-wide async processing - [Delaying Messages](https://docs.ecotone.tech/modelling/asynchronous-handling/delaying-messages.md): Delaying message delivery for scheduled processing - [Time to Live](https://docs.ecotone.tech/modelling/asynchronous-handling/time-to-live.md): Time to live for automatic message expiration - [Message Priority](https://docs.ecotone.tech/modelling/asynchronous-handling/message-priority.md): Message priority for controlling processing order - [Scheduling](https://docs.ecotone.tech/modelling/asynchronous-handling/scheduling.md): Scheduling PHP - [Dynamic Message Channels](https://docs.ecotone.tech/modelling/asynchronous-handling/dynamic-message-channels.md): Dynamic message channels for per-tenant routing and isolation - [Distributed Bus and Microservices](https://docs.ecotone.tech/modelling/microservices-php.md): Implementing Microservices and Event Driven Architecture in PHP - [Distributed Bus](https://docs.ecotone.tech/modelling/microservices-php/distributed-bus.md): Distributed Bus for cross-service messaging in PHP - [Distributed Bus Interface](https://docs.ecotone.tech/modelling/microservices-php/distributed-bus/distributed-bus-interface.md): Distributed Bus Interface for sending commands and events across services - [Distributed Bus with Service Map](https://docs.ecotone.tech/modelling/microservices-php/distributed-bus/distributed-bus-with-service-map.md): Distributed Bus with Service Map for multi-broker microservice communication - [Configuration](https://docs.ecotone.tech/modelling/microservices-php/distributed-bus/distributed-bus-with-service-map/configuration.md): Configuring Distributed Bus with Service Map - [Sharing Events with Streaming Channels](https://docs.ecotone.tech/modelling/microservices-php/distributed-bus/distributed-bus-with-service-map/sharing-events-with-streaming-channels.md): Sharing events between services with streaming channels - [Custom Features](https://docs.ecotone.tech/modelling/microservices-php/distributed-bus/distributed-bus-with-service-map/custom-features.md): Custom features for Distributed Bus with Service Map - [Shared Service Map](https://docs.ecotone.tech/modelling/microservices-php/distributed-bus/distributed-bus-with-service-map/shared-service-map.md): Shared Service Map for centralized service topology - [Non-Ecotone Application integration](https://docs.ecotone.tech/modelling/microservices-php/distributed-bus/distributed-bus-with-service-map/non-ecotone-application-integration.md): Integrating with other Languages and Frameworks - [Testing](https://docs.ecotone.tech/modelling/microservices-php/distributed-bus/distributed-bus-with-service-map/testing.md): Testing Distributed Bus and cross-service messaging - [AMQP Distributed Bus (Legacy)](https://docs.ecotone.tech/modelling/microservices-php/distributed-bus/amqp-distributed-bus-rabbitmq.md): AMQP Distributed Bus with RabbitMQ for legacy inter-service communication - [Configuration](https://docs.ecotone.tech/modelling/microservices-php/distributed-bus/amqp-distributed-bus-rabbitmq/configuration.md): Configuring AMQP Distributed Bus with RabbitMQ - [Message Consumer](https://docs.ecotone.tech/modelling/microservices-php/message-consumer.md): Message Consumer for consuming from external message brokers - [Message Publisher](https://docs.ecotone.tech/modelling/microservices-php/message-publisher.md): Message Publisher for publishing to external message brokers - [Business Workflows](https://docs.ecotone.tech/modelling/business-workflows.md): Building business workflows with Sagas, Orchestrators, and Handler Chaining in PHP - [Connecting Handlers with Channels](https://docs.ecotone.tech/modelling/business-workflows/connecting-handlers-with-channels.md): Learn how to connect message handlers using channels to build workflows - [Sagas: Workflows That Remember](https://docs.ecotone.tech/modelling/business-workflows/sagas.md): Learn how to build long-running workflows that remember state using Sagas - [Orchestrators: Declarative Workflow Automation](https://docs.ecotone.tech/modelling/business-workflows/orchestrators.md): Learn how to build predefined and dynamic workflows using Orchestrator - [Handling Failures](https://docs.ecotone.tech/modelling/business-workflows/handling-failures.md): Handling Failures and Exceptions in Sagas and Process Managers - [Migrations / Storage](https://docs.ecotone.tech/modelling/migrations-storage.md): Database migrations and storage management in Ecotone PHP - [Testing Support](https://docs.ecotone.tech/modelling/testing-support.md): Testing message-driven applications with Ecotone PHP - [Testing Messaging](https://docs.ecotone.tech/modelling/testing-support/testing-messaging.md): Testing Messaging architecture in PHP - [Testing Aggregates and Sagas with Message Flows](https://docs.ecotone.tech/modelling/testing-support/testing-aggregates-and-sagas-with-message-flows.md): Testing Aggregate, Saga in PHP - [Testing Event Sourcing Applications](https://docs.ecotone.tech/modelling/testing-support/testing-event-sourcing-applications.md): Testing Event Sourcing applications in PHP - [Testing Asynchronous Messaging](https://docs.ecotone.tech/modelling/testing-support/testing-asynchronous-messaging.md): Testing asynchronous communication in PHP --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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