React useEffect Guide

Golden rule

useEffect is for synchronizing a component with an external system. If no external system is involved, remove the Effect.

External systems include browser APIs, network connections, timers, third-party widgets, external stores, and raw data fetching when a framework or cache library is not available.

Workflow

1. Classify the Effect

For each Effect, name the external system it synchronizes with.

If there is no external system, replace the Effect with the React-native shape: