Deployment Patterns MOC

Deployment Patterns MOC

Map of Content for microservices deployment and cloud-native release patterns. Covers two layers: (1) Microservices infrastructure patterns (Phase 14: Sidecar, Ambassador, Strangler Fig, Service Mesh, Circuit Breaker, API Gateway) and (2) Cloud-native release patterns (Phase 15: Blue/Green, Canary, Rolling, Feature Flags, 12-Factor App). These patterns sit above the enterprise integration layer (DDD/EIP/CQRS/Saga) and address how services are deployed, evolved, and released safely in production.


Evolutionary Lineage Chains

How deployment and release patterns derive from GoF and enterprise ancestors.

ChainLineage
Proxy/InterceptionProxy-Pattern -> Sidecar-Pattern -> Ambassador-Pattern -> Service-Mesh-Pattern
Encapsulation/MigrationFacade-Pattern -> Anti-Corruption-Layer-Pattern -> Strangler-Fig-Pattern
Strategy/VariationStrategy-Pattern -> Feature-Flags-Pattern -> Canary-Release-Pattern -> Blue-Green-Deployment
Decorator/MiddlewareDecorator-Pattern -> Pipes-and-Filters -> Sidecar-Pattern

Microservices Infrastructure Patterns

Patterns for structuring and operating individual services within a distributed system.

PatternIntentSuitability Threshold
Sidecar-PatternAttach auxiliary functionality to a service without modifying itWhen cross-cutting concerns (logging, config, networking) must be language-agnostic
Ambassador-PatternProxy outbound traffic from a service through a dedicated helperWhen services need circuit breaking, routing, or telemetry on outbound calls
Service-Mesh-PatternCoordinate a fleet of sidecar proxies to manage all service-to-service communication10+ services AND dedicated platform team
Strangler-Fig-PatternIncrementally replace a legacy system by routing traffic to new implementationsWhen legacy modernisation is required but big-bang rewrite is too risky
Circuit-Breaker-PatternPrevent cascading failures by failing fast when a downstream service is unhealthyWhen services call unreliable downstream dependencies
API-Gateway-PatternSingle entry point for external clients, routing to internal microservicesWhen multiple microservices must be exposed through a unified external API

Infrastructure selection guide: Start with Circuit Breaker and API Gateway — they address the most universal failure modes (cascading failures and multi-service exposure). Add Sidecar and Ambassador when cross-cutting concerns (telemetry, retries, auth) threaten to pollute service code. Escalate to Service Mesh only when 10+ services and a dedicated platform team justify the operational overhead. Use Strangler Fig only when a big-bang rewrite is too risky.


Cloud-Native Release Strategies

Patterns for deploying new versions of services with controlled risk.

PatternIntentKey Constraint
Blue-Green-DeploymentAtomic switch between two identical production environmentsRequires 2x infrastructure capacity; DB schema must be backward-compatible
Canary-Release-PatternGradual traffic shift to new version based on observed metricsRequires automated rollback triggers; Feature Flags enable traffic splitting
Rolling-DeploymentReplace instances one-by-one until all run the new versionRequires stateless services; both versions coexist during rollout

Choosing a release strategy:

  • Blue/Green when: high-risk change, instant rollback needed, compliance/audit, budget for 2x capacity
  • Canary when: gradual confidence needed, observable metrics available, A/B testing desired
  • Rolling when: low-risk change, cost-constrained, stateless services, Kubernetes default is sufficient

For the full 8-row comparison table, see Blue-Green-Deployment#Choosing a Release Strategy.


Supporting Patterns

Foundational patterns that enable and underpin the release strategies above.

PatternRole
Feature-Flags-PatternRuntime strategy selection enabling Canary traffic splitting and Blue/Green pre-validation
12-Factor-AppFoundational methodology: stateless processes, config from environment, dev/prod parity

Cross-Layer References

These MOCs cover the upstream pattern layers that deployment patterns build upon.

  • GoF-Patterns-MOC — GoF patterns are upstream ancestors (Proxy, Facade, Strategy, Decorator originate here)
  • Enterprise-Patterns-MOC — DDD/EIP/CQRS/Saga sit between GoF and deployment layers; lineage chains connect all three

Sources

This MOC synthesizes patterns documented in Phases 14 (Microservices Deployment Patterns) and 15 (Cloud-Native Release Patterns). Individual pattern sources, implementation notes, and code examples are in their respective topic notes.