# What changed in camelcase

> 7 changes in camelcase 9 to 10 from its official release notes, upgrade guides and advisories: 5 breaking, 1 new APIs and options. Each one cited. Sources checked 2026-10-20. HTML: https://unstale.sh/npm/camelcase/

To see which of these apply to a repository, run `npx @unstale/cli init` in it.

## camelcase 10

### Breaking changes

- Decimal digits from all scripts are treated as numbers, so letters following them are capitalized. (10.0.0) — [release notes](https://github.com/sindresorhus/camelcase/releases/tag/v10.0.0)
- Node.js 22 is now required to use camelcase. (10.0.0) — [release notes](https://github.com/sindresorhus/camelcase/releases/tag/v10.0.0)
- Letters requiring surrogate pairs are handled as one character; pascalCase uppercases such a first letter, and uppercase letters of this type in the middle of a word are no longer lowercased. (10.0.0) — [release notes](https://github.com/sindresorhus/camelcase/releases/tag/v10.0.0)
- When capitalizeAfterNumber is false, uppercase letters after characters such as ! or @ are no longer lowercased. (10.0.0) — [release notes](https://github.com/sindresorhus/camelcase/releases/tag/v10.0.0)

## camelcase 9

### Breaking changes

- Node.js 20 is now required to use camelcase. (9.0.0) — [release notes](https://github.com/sindresorhus/camelcase/releases/tag/v9.0.0)

### New APIs and options

- Adds the capitalizeAfterNumber option. (9.0.0) — [release notes](https://github.com/sindresorhus/camelcase/releases/tag/v9.0.0)

### Fixes and other changes

- Leading underscores and dollar signs are now preserved. (9.0.0) — [release notes](https://github.com/sindresorhus/camelcase/releases/tag/v9.0.0)