Vengeance Blog

CAP Theorem in Practice

Consistency and availability tradeoffs during network partitions.

Distributed Systems1 minInspired by Brewer / Gilbert & Lynch

What CAP says

When partitions happen, distributed systems must choose between strong consistency and full availability for that operation.

Common mistakes

  • CAP is not a permanent global setting.
  • Partition tolerance is not optional in real networks.
  • Most systems pick tradeoffs per endpoint, not one label forever.

Practical design

For payments and identity, many teams prefer consistency during faults. For feeds and analytics counters, eventual consistency is often acceptable.