Distributed Systems Foundations

11 canonical primitives for distributed systems theory. Each primitive resolves a specific correctness or availability failure. Primitives are domain-agnostic: the same quorum math that governs database replication governs agent-state synchronisation; the same fencing tokens that prevent split-brain in a storage cluster prevent double-writes in a payment processor.

When to Apply

Apply distributed-systems primitives when:

• 2+ nodes participate in a write or shared state (replication, consensus)
• Network partitions are possible and must be tolerated (CAP/PACELC tradeoff)
• Idempotency, exactly-once, or fencing tokens are needed for safety
• Consistency level is being chosen (linearizable / sequential / causal / eventual)
• Multi-region or multi-AZ deployment with failover/quorum requirements