# On let vs const

DevFeed: [On let vs const](<https://devfeed.tech/articles/on-let-vs-const-36183.md>)

Original publisher: [Read original article](<https://overreacted.io/on-let-vs-const/>)

Published: 2019-12-22T00:00:00Z

Content type: opinion

Language: en

Sources: [Dan Abramov](<https://devfeed.tech/sources/dan-abramov.md>)

Topics: [JavaScript](<https://devfeed.tech/topics/javascript.md>), [Code](<https://devfeed.tech/topics/code.md>), [React Hooks](<https://devfeed.tech/topics/react-hooks.md>)

Tags: [eslint](<https://devfeed.tech/tags/eslint.md>), [immutability](<https://devfeed.tech/tags/immutability.md>), [javascript](<https://devfeed.tech/tags/javascript.md>), [mutation](<https://devfeed.tech/tags/mutation.md>), [react](<https://devfeed.tech/tags/react.md>), [react-hooks](<https://devfeed.tech/tags/react-hooks.md>)

## AI overview

This article examines the debate over using JavaScript let versus const. It summarizes arguments about reducing reassignment-related bugs, teaching mutation and assignment distinctions, React Hooks data flow, performance claims, and preserving intent, then presents the author's personal conclusion.

## Source excerpt

So which one should I use?