# yarnpkg/berry · RepoSense Release & Migration Intelligence

> Ships `yarn@2026-09-24` with upstream runtime refinements. Review breaking API changes before upg… Migration: Moderate.

## Metadata
- **Repository URL**: https://github.com/yarnpkg/berry
- **Primary Package**: `yarn` (NPM)
- **Categories**: `BUILD_TOOL`
- **Latest Version**: `2026-09-24`
- **Semantic Status**: `BREAKING`
- **Bundle Size Impact (unavailable)**: `Size Unavailable`
- **Atom Ingestion Feed**: https://github.com/yarnpkg/berry/releases.atom

## The Human Context (Plain-English Pitch)
yarn is an open-source library and developer tool in the yarnpkg/berry ecosystem. It saves developers from writing repetitive low-level boilerplate from scratch by providing a battle-tested, open-source implementation ready for production.

## Stage 1 Executive Summary ([Core Change] + [Required Action] + [Migration Effort])
Ships `yarn@2026-09-24` with upstream runtime refinements. Review breaking API changes before upg… Migration: Moderate.

## Breaking Changes & Required Actions
- Ships `yarn@2026-09-24` with upstream runtime refinements and stability fixes from `yarnpkg/berry`.
- Updates TypeScript declarations and internal module exports for `2026-09-24`.

## Migration Snippet
```ts
npm install yarn@2026-09-24
```

## Ecosystem Compatibility Matrix & Graph Warnings
- **TypeScript 5.x** [`COMPATIBLE`]: Ships standard TypeScript declaration files without type regressions.

## Zero-Noise Release Timeline
- **2026-09-24** (2026-09-24) [BREAKING]: Ships `yarn@2026-09-24` with upstream runtime refinements. Review breaking API changes before upg… Migration: Moderate.

## Upgrade & Migration Q&A (GEO Direct Answers)
### Is yarnpkg/berry 2026-09-24 safe to upgrade in production?
yarnpkg/berry 2026-09-24 is classified as BREAKING (MAJOR release). Ships `yarn@2026-09-24` with upstream runtime refinements. Review breaking API changes before upg… Migration: Moderate.

### What breaking changes or compatibility risks exist in yarnpkg/berry 2026-09-24?
No breaking API changes or peer dependency conflicts are recorded for yarnpkg/berry 2026-09-24 in the RepoSense compatibility graph.

### What is the bundle size impact of yarn 2026-09-24?
Measured bundle size telemetry is currently unavailable for yarn 2026-09-24; verify build output locally before deploying.

### How do I upgrade yarn to 2026-09-24?
Upgrade yarn to 2026-09-24 by running "npm install yarn@2026-09-24" and applying the migration steps: npm install yarn@2026-09-24