Integration

Translation boundary protecting a bounded context's model from upstream language corruption; structure (FACADE+ADAPTER); ACL vs Conformist vs Open-Host Service; migration use with Strangler Fig

REST vs gRPC vs GraphQL: decision table by traffic type; trade-off analysis across caching, schema, streaming, browser support, evolution; mixing protocols; chatty API anti-pattern

Six bounded context integration patterns grouped by team collaboration type; context map notation; model translation: stateless proxy (sync/async) and stateful aggregation (stream processing, BFF); private vs public events; Evans' originating eight-pattern taxonomy (Shared Kernel, Customer/Supplier, Conformist, ACL, Separate Ways, OHS, Published Language, CI) and transformation recipes

Strict/loose contract spectrum; consumer-driven contracts; stamp coupling; event schema evolution (forward/backward/full compatibility); schema registry; event design anti-patterns; Newman: structural vs semantic breakages, expansion changes, dual-version strategies; EIP: Format Indicator (version number/foreign key/embedded schema), Canonical Data Model

Coupling taxonomy: structural (Ca/Ce, Martin A/I/D, connascence), operational (Newman's implementation/temporal/deployment/domain types), contract (strict/loose, stamp coupling), integration-style spectrum (File Transfer → Messaging); coupling and quantum boundaries; coordinated deployments as coupling signal; concept leakage and flatten-when-publishing

*Enterprise Integration Patterns* — Hohpe & Woolf

the four EIP integration styles (File Transfer, Shared Database, RPI, Messaging); eight decision criteria; trade-offs and when to use which style

Command/Document/Event message types; one-way/req-resp/broadcast styles; Request-Reply (sync block vs async callback; Return Address; Correlation Identifier); point-to-point/pub-sub/datatype channels; Pub-Sub as distributed Observer (push vs pull; channel design); at-least-once delivery; guaranteed delivery; exactly-once via idempotency; invalid vs dead letter channel; backlogs; poison message isolation; competing consumers; data safety trade-off (publisher confirms + persistent queues + manual ACKs); quorum queues (RAFT); RabbitMQ internals; Pipes and Filters; Message Router; Message Bus; Messaging Bridge; Aggregator; Resequencer; Composed Message Processor; Scatter-Gather; Routing Slip; Process Manager; Message Broker (architectural pattern); Envelope Wrapper; Content Enricher; Content Filter; Claim Check; Normalizer; Canonical Data Model; Messaging Gateway; Messaging Mapper; Transactional Client; Polling Consumer; Event-Driven Consumer; Competing Consumers; Message Dispatcher; Selective Consumer; Durable Subscriber; Idempotent Receiver; Service Activator; Control Bus; Detour; Wire Tap; Message History; Message Store; Smart Proxy; Test Message; Channel Purger

When to use synchronous vs asynchronous communication; temporal coupling as the core distinction; availability chaining risk; async concerns (idempotency, ordering, correlation, observability); mixed model (sync north-south, async east-west); decision guide