planifest Distributed Consensus
Overview
Use this skill when system correctness depends on multiple nodes agreeing on state transitions under crash and partition conditions.
Scope Boundaries
- Replicated writes require explicit safety/liveness guarantees.
- Quorum and leadership behavior determine correctness.
- Membership changes and failover policy must be defined safely.
Shared References
- Consensus policy rules:
references/consensus-policy-rules.md
Templates And Assets
- Consensus policy template:
assets/consensus-policy-template.md
Inputs To Gather
- Replicated state machine requirements.
- Fault model (crash, partition, byzantine assumptions).
- Latency/availability targets and quorum constraints.
- Membership change and recovery expectations.
Deliverables
- Consensus policy decisions (quorum, election, commit semantics).
- Safety/liveness assumptions and risks.
- Operational policy for split-brain and degraded mode.
- Validation plan for failover and rejoin scenarios.
Workflow
- Capture policy baseline in
assets/consensus-policy-template.md. - Define safety invariants and availability targets.
- Select quorum, leadership, and commit rules using
references/consensus-policy-rules.md. - Define partition, degraded-mode, and recovery behavior.
- Define membership change strategy and validation sequence.
- Validate with failure simulation and state convergence checks.
Quality Standard
- Safety invariants are explicit (no divergent committed state).
- Liveness tradeoffs are acknowledged under partition conditions.
- Membership changes preserve quorum guarantees.
- Recovery/rejoin behavior is deterministic and tested.
Failure Conditions
- Stop when quorum or commit semantics are undefined.
- Stop when partition behavior can cause split-brain writes.
- Escalate when membership change procedure risks safety violation.