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CAP Theorem Sandbox

Partition, then choose — consistency or availability

Three replicas, one network. Trigger a partition, then write and read across the split. In CP mode the minority side refuses. In AP mode it answers, sometimes with stale or divergent values. The theorem is not a recommendation; it is a wall you bump into.

A / v0B / v0C / v0all replicas connected
write from →
read from →

no operations yet

During a partition you pick a failure mode: refuse to answer (CP), or answer but risk stale data (AP). The theorem is not that one is better — it is that there is no third door.

CAP Theorem Sandbox — Internet Systems Labs · hbar.university