Microservices & Architectural Patterns

Evaluate organizational and technical trade-offs: Deployment velocity, blast radius, cognitive load, network latency tax, and Conway's Law.

Pragmatic decomposition guidelines: The Modular Monolith, premature distributed system traps, and clear indicators for service extraction.

Define clean microservice boundaries: Eric Evans' DDD, Bounded Contexts, Ubiquitous Language, Aggregates, and Domain Events.

Coordinate microservices: Synchronous RPC (gRPC/REST), Asynchronous messaging (Kafka/RabbitMQ), and Hybrid Choreography.

Offload networking from application code: Control plane vs Data plane, mTLS zero-trust encryption, traffic shifting, and distributed telemetry.

Combine data across microservices: In-memory parallel fan-out aggregation, scatter-gather, timeout handling, and partial degradation.

Safely migrate legacy monoliths to microservices: Martin Fowler's pattern, routing proxies, dual-writing, dark launching, and gradual sunsetting.

Enforce true domain encapsulation: Private databases, independent schema migrations, polyglot storage, and preventing backdoor table coupling.

Recognize architectural decay: Distributed coupling, coordination bottlenecks, conflicting ORM migrations, and connection pool exhaustion.

Coordinate state across isolated service databases: XA/2PC blocking limits, Choreography/Orchestration Sagas, and Try-Confirm-Cancel (TCC).

Prevent cascading system collapse: CLOSED, OPEN, and HALF-OPEN states, failure rate thresholds, reset timeouts, and Resilience4j/Envoy.

Isolate resource pools: Ship hull compartments analogy, dedicated thread pools per service, semaphore isolation, and preventing resource starvation.

Prevent self-inflicted retry stampedes: Linear vs Exponential backoff, Full Jitter, Equal Jitter, Decorrelated Jitter, and retry budgets.

Prevent thread hanging: Connection timeouts, Socket read timeouts, Gateway timeouts, and Deadline Propagation in gRPC/HTTP.

Maintain user experience during partial outages: Stale cache fallbacks, default static responses, feature shedding, and degraded UX tiers.

Extend container capabilities without modifying application code: Logging sidecars, proxy sidecars (Envoy), security sidecars, and localhost IPC.

Abstract outbound connectivity: Client-side connection pooling, circuit breaking, protocol translation, and sharded database routing.

Isolate modern architectures from legacy systems: Domain translation, semantic adapters, facade layers, and preventing legacy domain leakage.

Evaluate Function-as-a-Service: Cold starts, execution time limits, statelessness, auto-scaling to zero, and total cost of ownership (TCO).

Design scalable distributed reactive systems: Event choreography, Saga orchestration (Temporal/Camunda), transactional outbox pattern, and change stream integration.