Patterns

Active Object

The Active Object pattern provides a way to decouple method execution from method invocation. It introduces a separate object (the Active Object) responsible for managing all method requests and executing them within its own thread, avoiding complexities and potential issues with direct thread management by client …

Active Record

creational DDD

The Active Record pattern is a design pattern where objects representing data, typically database records, carry both data and the logic to interact with the database. Instead of having a separate object to manage database access (like a Data Access Object), the Active Record object itself is responsible for reading …

Adapter Container

behavioral integration

The Adapter Container pattern addresses integration challenges when a client requires a service through a specific interface, but the available service provides a different, incompatible interface. This pattern encapsulates the legacy service within an adapter, translating requests from the client’s interface to the …

Aggregate Root

DDD behavioral

The Aggregate Root pattern is a core concept in Domain-Driven Design (DDD) used to define transactional consistency boundaries. It designates a specific entity within a cluster of associated objects (the aggregate) as the single point of access for modifying the aggregate’s state. This root is responsible for ensuring …

Aggregator

behavioral integration

The Aggregator pattern provides a unified interface to a number of disparate subsystems. Instead of a client having to interact with each subsystem directly, it interacts with the aggregator, which then dispatches requests to the appropriate subsystems. The aggregator then combines the results from these subsystems …

Anti-Corruption Layer

architectural integration DDD

The Anti-Corruption Layer (ACL) is an architectural pattern used to isolate a core application from problematic or poorly understood external systems (often legacy systems). It acts as a translation layer, preventing the complexities, inconsistencies, and potential errors of the external system from polluting the …

API Composition

architectural integration

API Composition is an architectural pattern that allows building new APIs by combining multiple existing APIs. Instead of creating monolithic APIs that handle all functionality, or requiring clients to interact with numerous individual APIs, an orchestrator API aggregates and transforms data from several backend APIs …

Balking

behavioral state

The Balking pattern is a behavioral pattern that allows an object to postpone the execution of a request until a specific condition is met. It essentially prevents an object from performing an action if it’s already in a particular state, often a “busy” or “occupied” state. This is …

Blue-Green Deployment

deployment operational

Blue-Green Deployment is a release strategy that reduces downtime and risk by running two identical environments, ‘blue’ and ‘green’. The ‘blue’ environment serves all production traffic, while the ‘green’ environment is kept as a staging area for new releases. Once the …

Bulkhead

resilience behavioral

The Bulkhead pattern isolates parts of an application from each other, preventing failures in one part from cascading and bringing down the entire system. It’s inspired by the compartmentalization of a ship’s hull – if one section is breached, the bulkheads prevent the flooding from spreading to the rest …