Are you familiar with the CAP theorem? Have you used it in your work?

The CAP theorem states that a distributed system cannot simultaneously guarantee all three properties: Consistency, Availability, and Partition tolerance. Only two of the three can be ensured.

• Consistency — all nodes see the same data at the same time.
• Availability — each request receives a response (successful or error) without long delays.
• Partition tolerance — the system continues to operate despite network splits between nodes.

In real distributed systems, where network partitions are possible, a choice is usually made between consistency and availability. For example, some projects had to sacrifice immediate consistency for high availability and fault tolerance.