🔎 What is pnpm?

pnpm (Performant npm) is a fast, disk space–efficient package manager for JavaScript projects. It was created to solve some of the biggest pain points with npm and yarn, such as slow installs and excessive disk usage.

The core idea behind pnpm is its unique node_modules structure that uses symlinks to avoid duplication of packages. Instead of copying dependencies repeatedly for every project, pnpm stores them in a global content-addressable store and links them where needed.

PNPM vs. NPM: The Hard Numbers Comparison

PNPM’s core innovation lies in its unique dependency structure, which uses a content-addressable store and symbolic links instead of simply copying files for every project. This change fundamentally alters performance metrics.

Metric Traditional NPM PNPM (Performant NPM) Impact & Explanation
Installation Speed (Cold Cache) ≈ 29−57 seconds ≈ 6−14 seconds Up to 2−3× Faster, PNPM drastically reduces the time spent downloading and extracting by reusing packages already in its global store.
Installation Speed (Hot Cache) ≈ 1.5−2 seconds ≈ 700−900 milliseconds Up to 2× Faster. Even with an existing cache, PNPM’s linking process is more efficient than NPM’s hoisting/copying.
Disk Space Usage High (e.g., 5 GB for 5 large projects) Low (e.g., ≈1 GB for 5 large projects) 50-70% Savings on disk space across all your projects. A single version of a dependency is stored once and linked everywhere.
Dependency Tree Flat (Hoisted) Strict (Content-Addressable) Prevents “Phantom Dependencies.” PNPM ensures your code can only access packages explicitly listed in package.json, leading to fewer elusive runtime bugs.

Reasons to Switch to PNPM Today

1. Blazing Fast CI/CD Pipelines 🚀

The biggest pain point for large teams is slow build times. When a CI/CD job runs npm install, it’s often downloading the same packages thousands of times across various builds. With PNPM, you can cache the global content store. Subsequent builds, even on new branches, become lightning fast because the files are already there, dramatically reducing both pipeline runtime and CI infrastructure costs.

2. Massive Hard Drive Relief 💾

Do you work on multiple projects that share core dependencies like React, Vue, or Tailwind? Every time you run npm install, you duplicate gigabytes of files. PNPM’s hard-linking strategy treats your hard drive like a shared library. If a dependency is already in the central store, it just links it into your project’s node_modules instead of making a full copy. No more bloated node_modules folders eating up precious SSD space.

3. Fewer “It Works on My Machine” Bugs 🐛

NPM’s default flat node_modules structure “hoists” dependencies, which can unintentionally give your code access to packages you didn’t explicitly install (Phantom Dependencies). This leads to unpredictable bugs when dependencies get updated or when you try to publish a package.

PNPM’s strict, symlinked structure eliminates this. Your project only sees what it declared in package.json, forcing developers to manage dependencies correctly and leading to a cleaner, more stable dependency graph.

4. Workspaces for Monorepos

pnpm has built-in support for workspaces, making it an excellent choice for monorepo architectures. Managing multiple packages across a large codebase becomes seamless.

⚙️ How to Get Started

  1. Install pnpm npm install -g pnpm

  2. Initialize a Project pnpm init

  3. Install Dependencies pnpm install react react-dom

  4. Run Scripts pnpm respects the package.json scripts just like npm: pnpm run dev

🛠 Example: Using pnpm Workspaces (Monorepo)

A common use case is monorepo development where multiple packages are managed in one repo.

Step 1: Create pnpm-workspace.yaml

packages:
  - "packages/*"
  - "apps/*"

Step 2: Install dependencies across all workspaces

pnpm install

Step 3: Run scripts for a specific package

pnpm --filter my-app dev

This approach makes dependency management in large codebases organized and efficient.

👉 Give it a try in your next project and experience the difference.

💡 Pro Tip: You can migrate an existing project to pnpm in just a few minutes. Run pnpm import to convert your lockfile from npm or Yarn, and you’re ready to go.