Concurrency Patterns

Trigger Boundary

• •Use when parallel execution, coordination, or distributed failure semantics are central.
• •Do not use for UX interaction design concerns; use design-related skills.
• •Do not use for single-query database tuning only; use db-query-optimization.

Goal

Ensure correctness and resilience under concurrency and partial failures.

Inputs

• •Change scope and risk profile
• •Domain evidence for shared-state safety, coordination primitives, and contention control
• •Operational, compliance, and rollout constraints

Outputs

• •Concurrency pattern selection record
• •Decision log for shared-state safety, coordination primitives, and contention control
• •Verification checklist with measurable pass-fail criteria

Workflow

1. •Clarify outcomes and hard constraints for shared-state safety, coordination primitives, and contention control.
2. •Produce options and select an approach for shared-state safety, coordination primitives, and contention control.
3. •Evaluate trade-offs across security, performance, operability, and maintainability.
4. •Verify decisions using race-condition and contention stress tests.
5. •Publish decisions, residual risks, and accountable follow-up actions.

Quality Gates

• •Scope and assumptions for shared-state safety, coordination primitives, and contention control are explicit and reviewable.
• •Decision rationale is backed by evidence instead of preference.
• •Rollout and rollback criteria are defined when production impact exists.
• •Residual risks have owners, due dates, and verification steps.

Failure Handling

• •Stop when selected pattern allows race conditions or deadlocks.
• •Escalate when accepted risk exceeds team policy thresholds.