State Management Decision Authority — Part 02

Your React state doesn't need to be global just because two components need it.

In Part 1, useState vs useReducer: Stop Choosing Tools Before Understanding State , I explored an architectural idea I call the State Management Decision Authority : choosing state management strategies through consistent criteria rather than tool preferences.

One of those criteria deserves a deeper discussion:

State Ownership.

Because sharing state and globalizing state are two very different decisions.

1. The Checkout Problem

Imagine a checkout feature with three components:

function Checkout () { return ( <> < ShippingForm /> < OrderSummary /> < PaymentSection /> </> ); }

Enter fullscreen mode

Exit fullscreen mode

Each component has a different responsibility.

ShippingForm collects the delivery address.

OrderSummary displays the shipping cost.

PaymentSection checks whether checkout requirements are satisfied.

But they all depend on some of the same information.

If…