architecture-serverlesslisted

# Architecture Serverless ## Overview Use this skill to design serverless systems that are cost-aware, failure-tolerant, and operationally predictable. ## Scope Boundaries - Traffic is variable or bursty and elastic scaling is valuable. - Team capacity for infrastructure operations is limited. - Workloads are naturally event-driven or request/response with bounded execution. ## Core Judgments - Compute model: function granularity, execution time bounds, and concurrency profile. - State model: where session/process state lives outside function runtime. - Integration model: event source guarantees, retry semantics, and idempotency. - Cost model: invocation frequency, cold-start impact, data transfer/storage economics. ## Practitioner Heuristics - Keep functions narrow by business action, not by tiny technical helpers. - Externalize state deliberately (DB/cache/object store) and design for retries. - Control concurrency at event source and downstream dependency limits. - Treat timeouts as business behavior decisions, not only platform defaults. ## Workflow 1. Profile workload shape and latency/cost sensitivity. 2. Design event and request paths with explicit idempotency rules. 3. Choose managed services for state, orchestration, and messaging. 4. Define concurrency limits and backpressure behavior. 5. Model cost and failure behavior under peak and degraded conditions. 6. Record escape hatches for workloads that outgrow serverless constraints. ## Common Failure Modes - Hidd