# What changed in sass-loader

> 10 changes in sass-loader 16 to 17 from its official release notes, upgrade guides and advisories: 3 breaking. Each one cited. Sources checked 2026-10-17. HTML: https://unstale.sh/npm/sass-loader/

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

## sass-loader 17

### Breaking changes

- Support for the legacy Sass JS API has been removed. (17.0.0) — [release notes](https://github.com/webpack/sass-loader/releases/tag/v17.0.0)
- The minimum supported NodeJS version is now 22.11.0. (17.0.0) — [release notes](https://github.com/webpack/sass-loader/releases/tag/v17.0.0)
- Support for node-sass has been removed. (17.0.0) — [release notes](https://github.com/webpack/sass-loader/releases/tag/v17.0.0)

### Behavior and default changes

- The api option now defaults to auto, which enables the modern compiler when supported and reuses a long-running compiler across files; otherwise it falls back to the modern API. (17.0.0) — [release notes](https://github.com/webpack/sass-loader/releases/tag/v17.0.0)

### Tooling

- The exports field exposes both ESM and CommonJS builds, allowing ESM consumers to import the loader directly while CommonJS consumers continue to use require. (17.0.0) — [release notes](https://github.com/webpack/sass-loader/releases/tag/v17.0.0)
- Types have been added. (17.0.0) — [release notes](https://github.com/webpack/sass-loader/releases/tag/v17.0.0)

### Fixes and other changes

- Removes the BOM from compiled CSS and shifts source maps accordingly, preventing it from breaking a CSS rule when tools move @import at-rules above it. (17.0.1) — [release notes](https://github.com/webpack/sass-loader/releases/tag/v17.0.1)

## sass-loader 16

### Performance

- Caches filesystem calls for the modern API. (16.0.6) — [release notes](https://github.com/webpack/sass-loader/releases/tag/v16.0.6)

### Tooling

- Updates the peer dependency for @rspack/core v2, allowing sass-loader to declare compatibility with it. (16.0.7) — [release notes](https://github.com/webpack/sass-loader/releases/tag/v16.0.7)

### Fixes and other changes

- Normalizes separators in getPossibleRequests on Windows. (16.0.8) — [release notes](https://github.com/webpack/sass-loader/releases/tag/v16.0.8)