Introduction to CRDTs

Conflict-free Replicated Data Types, or CRDTs for short, are a fascinating data structure at the crossroads of Computer Science and Distributed Systems. They allow for distributed and concurrent updates while guaranteeing that all machines in a network will ultimately reach the same result without conflicts. Very much like the plot of a time-travel movie where multiple timelines coexist but eventually converge to a single outcome.

Often, we face scenarios where multiple computers need to share and edit the state of an application without data conflicts. Think about a real-time, multi-user collaborative application like Google Docs. Each user's operations need to be merged seamlessly without overwriting the work of others. This is precisely where CRDTs shine.

There are various types of CRDTs, including but not limited to Grow-Only Set (G-Set), Observed-Remove Set (OR-Set), and Positive-Negative Counter (PN-Counter). Like different film genres, each comes with its own set of features suitable for different types of plots (applications).

To put it in a more finance-centric context, suppose you're dealing with a highly volatile stock market where transactions happen continuously from multitudes of sources. CRDTs would be perfect for ensuring the consistency of data updates, rather like a decentralized ledger in cryptocurrency usage.

In the code section, we will review a simple Python playground to better understand the behaviour of a simple CRDT.