Microservices

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name: microservices description: Deep microservices workflow—service boundaries, data ownership, synchronous vs async integration, contracts, deployment independence, and operational complexity. Use when splitting a monolith, reviewing service boundaries, or debugging distributed failures.

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Microservices (Deep Workflow)

Microservices trade code simplicity for operational and contract complexity. Justify each boundary with ownership and data isolation—not fashion.

When to Offer This Workflow

Trigger conditions:

Splitting the monolith; coupling blocks independent deploys

Latency cascades, partial failures, contract breaks

Conway’s law alignment between teams and services

Initial offer:

Use six stages: (1) goals & constraints, (2) boundaries & data ownership, (3) integration patterns, (4) contracts & versioning, (5) reliability patterns, (6) ops & governance). Confirm org maturity and platform capabilities.

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Stage 1: Goals & Constraints

Goal: Why not a modular monolith first?

Valid drivers

Independent deploy cadence per team

Different scaling profiles or stacks

Clear domain ownership and blast-radius isolation

Costs

Distributed transactions, harder debugging, broader test matrix

Exit condition: Explicit assumption that modular monolith was considered.

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Stage 2: Boundaries & Data Ownership

Goal: One service owns each aggregate’s write path; no shared writable tables across services.

Practices

Bounded contexts from DDD when helpful

Exit condition: Entity → owning service map.

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Stage 3: Integration Patterns

Goal: Sync HTTP/gRPC vs async events—match consistency needs.

Patterns

Sagas or outbox for multi-step business processes

Exit condition: Sequence diagrams for top three flows.

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Stage 4: Contracts & Versioning

Goal: Backward-compatible evolution; consumer-driven contracts optional.

Practices

Deprecation policy published

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Stage 5: Reliability Patterns

Goal: Timeouts, retries with backoff, circuit breakers, bulkheads; idempotent handlers for retries.

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Stage 6: Ops & Governance

Goal: Service catalog, SLIs on dependency edges, golden paths for new services.

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Final Review Checklist

[ ] Boundary and data ownership clear

[ ] Integration style matches consistency needs

[ ] Contract versioning policy exists

[ ] Reliability patterns applied at boundaries

[ ] Ops ownership and catalog in place

Tips for Effective Guidance

Microservices without delivery maturity often fail—say so explicitly.

Shared databases are hidden coupling—flag them.

The network is not reliable—design for partial failure.

Handling Deviations

Small teams: strong bias toward modular monolith or few services.