Replication
Update Propagation: Moving a Change Across Copies
How updates move from a source of truth to caches, read models, indexes, and other replicas.
Transactions
Two Phase Commit: Coordinating a Commit
A practical explanation of two phase commit, prepare, commit, and why the coordinator matters.
Transactions
Serialized Transactions: One Clear Order
How serialized transactions make concurrent work behave as if it ran one transaction at a time.
Consensus
Raft Consensus: Leader and Followers in Plain English
A practical explanation of Raft consensus using leader election and replicated log commitment.
Replication
Quorum: Enough Votes to Trust the Answer
A simple explanation of quorum reads and writes through a three replica example.
CAP
Partition Tolerance: Keep Rules During a Split
What partition tolerance means in practice and how to design behavior for broken communication.
Ordering
Ordering: Decide What Happened First
How ordering rules prevent consumers and replicas from applying events in unsafe ways.
Failures
Network Partitions: Designing for Broken Links
A practical explanation of network partitions and why services need explicit rules when nodes cannot talk.
Cluster State
Membership: Who Is in the Cluster
Why cluster membership is a first class concept in distributed systems.