# Algorithms

Distributed systems lose, delay, and duplicate messages, and every fix for that has its own name. In this article, we build a distributed systems cheat sheet: 20 concepts from CAP to sagas, each with an example, its cost, and a link to the deep dive.

This week: bool.dev explains how Raft commits writes and survives failures; Uber composes search indexes across independently owned services; Meta moves reusable privacy checks into data-access libraries; and LinkedIn connects user interactions to backend traces with OpenTelemetry.

How Raft keeps several servers in agreement when any of them can crash: one leader, a majority vote, and a write that counts only after most servers store it. Explained step by step, with diagrams and no math.