# pnpm — Fast, Disk-Space Efficient Package Manager

> pnpm is a fast, disk-space efficient package manager for Node.js. Uses a content-addressable store and symlinks to avoid duplicating packages across projects — saves gigabytes and installs 2x faster than npm.

## Install

Save the content below to `.claude/skills/` or append to your `CLAUDE.md`:

## Quick Use

```bash
# Install
npm install -g pnpm
# Or via Corepack (Node 16+)
corepack enable

# Use in a project
pnpm install
pnpm add react
pnpm dlx create-vite my-app
```

Monorepo workspace:
```yaml
# pnpm-workspace.yaml
packages:
  - "apps/*"
  - "packages/*"
```

```bash
pnpm -r build        # run build in all packages
pnpm --filter web dev # run dev in the web package
```

## Intro

pnpm is a fast, disk-space efficient package manager. Uses a content-addressable store + symlinks so every version of every package exists once on disk, shared across all your projects. Solves npm/yarn disk bloat and duplication.

- **Repo**: https://github.com/pnpm/pnpm
- **Stars**: 34K+
- **Language**: TypeScript
- **License**: MIT

## What pnpm Does

- **Fast installs** — 2-3x faster than npm
- **Disk efficient** — global content-addressable store (~/.pnpm-store)
- **Strict node_modules** — no phantom dependencies
- **Monorepo** — first-class workspace support
- **Deterministic** — pnpm-lock.yaml
- **Catalogs** — shared version ranges across workspace
- **Patches** — patch-package built in

## Architecture

Global store at `~/.pnpm-store/v3` holds all package tarballs (content-addressed). Each project gets a `node_modules/.pnpm` directory with hardlinks to the store, then symlinks in `node_modules/` to expose direct deps. Non-direct deps stay hidden (no phantom deps).

## Self-Hosting

CLI tool — install locally, no server.

## Key Features

- 2-3x faster than npm/yarn classic
- Up to 50% disk space savings
- Strict dependency resolution
- Workspace/monorepo first-class
- `pnpm dlx` for one-off commands
- Built-in `pnpm patch` for upstream fixes
- Catalogs (v9+) for shared versions
- Side-effects cache

## Comparison

| Manager | Speed | Disk | Monorepo | Strict |
|---|---|---|---|---|
| pnpm | Fast | Best | First-class | Yes |
| Yarn Berry | Fast | Medium | First-class | PnP |
| npm | Slowest | Worst | Workspaces | No |
| Bun | Fastest | Good | Basic | No |

## FAQ

**Q: Will it break existing projects?**
A: A few older packages that rely on phantom deps will throw errors. Fix: add them explicitly to `package.json` or use `public-hoist-pattern`.

**Q: Does it pair with Turborepo/Nx?**
A: Perfectly. pnpm handles dependencies; Turborepo/Nx handle task orchestration and caching.

**Q: Can it replace Yarn workspaces?**
A: Yes. Migration usually just involves moving `workspaces` from `package.json` into a `pnpm-workspace.yaml` file.

## Sources & Credits

- Docs: https://pnpm.io
- GitHub: https://github.com/pnpm/pnpm
- License: MIT

---
Source: https://tokrepo.com/en/workflows/pnpm-fast-disk-space-efficient-package-manager-2f0e07ae
Author: AI Open Source