NPM Package Managers Comparison: npm vs Yarn vs pnpm

Introduction

The JavaScript ecosystem has evolved significantly over the years, and with it, the tools for managing dependencies. This article provides a comprehensive comparison of the four major package managers: npm, Yarn Classic (1.x), Yarn Berry (2.x+), and pnpm, with a special focus on monorepo management capabilities.

TL;DR - Which Package Manager Should I Use?

• npm: Default choice for simple projects, comes with Node.js
• pnpm: Best for monorepos and when disk space matters (up to 80% savings)
• Yarn Classic: Legacy projects only - consider migrating to pnpm or Yarn Berry
• Yarn Berry: Cutting-edge features with PnP, but requires ecosystem compatibility

Quick Decision Guide:

• Small project, getting started → npm
• Large monorepo or multiple projects → pnpm
• Need specific Yarn features → Yarn Berry
• Maintaining existing project → Keep current, plan migration

Quick Overview

Popularity and Adoption

Market Share and Trends

Usage Statistics (2024)

According to independent reviews and survey results:

• npm: 56.6% market share (default choice)¹²
• Yarn Classic: 21.5% (legacy but stable)¹²
• pnpm: 19.9% (rapidly growing—predicted to reach 25-30% by end of 2025 but predictions are speculative)¹²³
• Yarn Berry: Remains a niche tool with low market share; specific numbers are rarely published, but industry discussion places it below npm, Yarn Classic, and pnpm¹²

The Software House's 2024 State of Frontend Report (over 6,000 developers):
"npm is the most widely used package manager (56.6% of votes), followed by Yarn Classic (21.5%) and pnpm (19.9%)"¹².

Installation Speed and Performance

Benchmark Comparison

Benchmark Comparison

*Monorepo install values are relative: pnpm is consistently the fastest and most space-efficient, especially as the number of projects grows⁴⁵⁶⁷.

Performance Characteristics

• npm: Moderate speed, improved in v7+, now supports parallel downloads since v5⁶.
• Yarn Classic: Parallel package downloads, deterministic installs, stable but not actively developed⁶.
• Yarn Berry: Plug'n'Play technology, zero-installs, fastest in some scenarios, ecosystem compatibility needs attention⁶.
• pnpm: Content-addressable storage and global hard links drastically reduce disk space in multi-project setups (up to 70–80% savings); fastest for monorepos and cached installs⁴⁵⁸⁷.

Performance Characteristics

npm

• Moderate speed
• Improved significantly in v7+
• Parallel downloads since v5

Yarn Classic

• Parallel package downloads
• Deterministic installs
• Offline mode support

Yarn Berry

• Plug'n'Play eliminates node_modules
• Near-instant installs with zero-installs
• Requires ecosystem compatibility

pnpm

• Content-addressable storage
• Hard links save disk space (up to 80% reduction)⁴⁵⁸
• Fastest for monorepos
• Fastest cached installs (0.73s)⁶

Cache Management

Cache Location and Structure

• npm: Default cache is ~/.npm (or %AppData%\npm-cache on Windows), stores package tarballs and metadata⁹¹⁰.
• Yarn Classic: Caches tarballs and metadata, default ~/.cache/yarn, but can be customized¹¹.
• Yarn Berry: Uses .yarn/cache directory in each project, storing ZIP archives of dependencies, often committed for offline/CI installs¹².
• pnpm: Global cache at ~/.pnpm-store, uses hard links or symlinks from global store to each project's node_modules (saves ~70% disk space when used across multiple projects)⁴⁵⁸⁷.

Cache Commands

# npm
# Forcefully clears the entire npm cache
npm cache clean --force
# Verifies cache integrity and cleans up corrupted entries
npm cache verify
# Lists cached packages (deprecated in newer versions, use npm cache verify instead)
npm cache ls

# Yarn Classic
# Removes all cached packages
yarn cache clean
# Shows all cached packages
yarn cache list
# Displays the cache directory path
yarn cache dir

# Yarn Berry
# Removes all cached packages (--all flag clears everything)
# Cache is project-local in .yarn/cache directory
yarn cache clean --all

# pnpm
# Removes unreferenced packages from the store
pnpm store prune
# Shows information about the store (size, integrity)
pnpm store status
# Displays the path to the pnpm store
pnpm store path

Cache Policies

npm

• Automatic cache management
• Corruption detection (npm cache verify)
• TTL-based invalidation

Yarn Classic

• Persistent cache
• Offline mirror support
• Manual cleanup required
• Integrity check with yarn check --integrity

Yarn Berry

• Zero-installs philosophy
• Commit cache to git (optional)
• Predictable CI builds

pnpm

• Global store deduplication
• Automatic garbage collection (pnpm store prune)
• Hard link optimization
• Store verification with pnpm store status

Dependency Structure and Linking

Directory Structures

npm/Yarn Classic - Nested Structure:

project/
├── node_modules/
│   ├── react/
│   │   ├── package.json
│   │   └── node_modules/
│   │       └── loose-envify/
│   ├── react-dom/
│   │   └── node_modules/
│   │       └── loose-envify/
│   └── express/

pnpm - Flat with Symlinks:

project/
├── node_modules/
│   ├── .pnpm/
│   │   ├── react@18.2.0/
│   │   │   └── node_modules/
│   │   │       └── react/
│   │   └── express@4.18.2/
│   ├── react -> .pnpm/react@18.2.0/node_modules/react
│   └── express -> .pnpm/express@4.18.2/node_modules/express

Yarn Berry - Plug'n'Play:

project/
├── .yarn/
│   ├── cache/
│   │   ├── react-npm-18.2.0-abc123.zip
│   │   └── express-npm-4.18.2-def456.zip
│   └── pnp.cjs
├── .pnp.loader.mjs
└── package.json

Local Package Development

# npm
npm link ../my-package
npm link my-package

# Yarn Classic
yarn link
cd ../project && yarn link my-package

# Yarn Berry
yarn link ../my-package

# pnpm
pnpm link ../my-package
# or use workspace protocol

Linking Comparison

Monorepo Management

Workspace Configuration

npm/Yarn Classic - package.json:

{
  "workspaces": [
    "packages/*",
    "apps/*"
  ]
}

Yarn Berry - package.json:

{
  "workspaces": [
    "packages/*",
    "apps/*"
  ]
}

pnpm - pnpm-workspace.yaml:

packages:
  - 'packages/*'
  - 'apps/*'
  - '!**/test/**'

Workspace Features Comparison

Monorepo Commands

# npm (v7+)
npm install --workspace=package-a
npm run build --workspaces
npm run test --workspace=package-a

# Yarn Classic
yarn workspace package-a add lodash
yarn workspaces run build
yarn workspaces info

# Yarn Berry
yarn workspace package-a add lodash
yarn workspaces foreach run build
yarn constraints check

# pnpm
pnpm add lodash --filter package-a
pnpm run --recursive build
pnpm run --filter "./packages/**" test

Advanced Monorepo Features

npm

• Basic workspace support
• Limited filtering options
• Use npm ls to visualize workspace dependencies

Yarn Classic

• Mature workspace implementation
• Good inter-package resolution
• Limited tooling

Yarn Berry

• Constraints engine for validation (enforces dependency rules)
• Protocol support (workspace:, portal:, exec:, patch:)
• Advanced plugin system
• Interactive upgrade workflow
• yarn explain for peer dependency debugging

pnpm

• Powerful filtering syntax
• Catalog protocol for version management
• Excellent performance at scale
• Built-in changeset support
• pnpm why -r for workspace-wide dependency analysis

Monorepo Performance

CI/CD Integration

GitHub Actions

npm:

- uses: actions/setup-node@v4
  with:
    node-version: '22'
    cache: 'npm'
- run: npm ci

Yarn Classic:

- uses: actions/setup-node@v4
  with:
    node-version: '22'
    cache: 'yarn'
- run: yarn install --frozen-lockfile

Yarn Berry:

- uses: actions/setup-node@v4
  with:
    node-version: '22'
- run: corepack enable
- run: yarn install --immutable

pnpm:

- uses: pnpm/action-setup@v4
  with:
    version: 10
- uses: actions/setup-node@v4
  with:
    node-version: '22'
    cache: 'pnpm'
- run: pnpm install --frozen-lockfile

GitLab CI

npm:

install-npm:
  image: node:22-alpine
  script:
    - npm ci
  cache:
    key: npm-$CI_COMMIT_REF_SLUG
    paths:
      - .npm/

Yarn Classic:

install-yarn-classic:
  image: node:22-alpine
  script:
    - yarn install --frozen-lockfile
  cache:
    key: yarn-$CI_COMMIT_REF_SLUG
    paths:
      - .yarn-cache/

Yarn Berry:

install-yarn-berry:
  image: node:22-alpine
  script:
    - corepack enable
    - yarn install --immutable
  cache:
    key: yarn-berry-$CI_COMMIT_REF_SLUG
    paths:
      - .yarn/cache/

pnpm:

install-pnpm:
  image: node:22-alpine
  script:
    - corepack enable
    - pnpm install --frozen-lockfile
  cache:
    key: pnpm-$CI_COMMIT_REF_SLUG
    paths:
      - .pnpm-store/

Docker Integration

Multi-stage Dockerfile example:

# Use Node.js 22
FROM node:22-alpine AS base

# Install dependencies only when needed
FROM base AS deps
WORKDIR /app

# Copy package files
COPY package*.json ./
# Choose your package manager
RUN npm ci --only=production

# Development image
FROM base AS dev
WORKDIR /app
COPY package*.json ./
RUN npm ci
COPY . .
CMD ["npm", "run", "dev"]

# Production image
FROM base AS production
WORKDIR /app
COPY --from=deps /app/node_modules ./node_modules
COPY . .
RUN npm run build
CMD ["npm", "start"]

Dependency Management Commands

Command Comparison Table

Upgrading All Dependencies

npm:

# Update to latest allowed by package.json
npm update

# Update to latest versions (requires npm-check-updates)
npx npm-check-updates -u
npm install

Yarn Classic:

# Interactive
yarn upgrade-interactive --latest

# All to latest
yarn upgrade --latest

Yarn Berry:

# Interactive with groups
yarn upgrade-interactive

# Plugin for more power
yarn plugin import interactive-tools
yarn upgrade-interactive

pnpm:

# Interactive
pnpm update --interactive --latest

# All to latest
pnpm update --latest -r

Version Bumping

# npm
npm version patch/minor/major

# Yarn (all versions)
yarn version --patch/--minor/--major

# pnpm
pnpm version patch/minor/major

# Monorepo version bumping
# npm - manual or use tools like lerna
# Yarn Berry - yarn version check --interactive
# pnpm - use changesets
pnpm changeset
pnpm version-packages

Built-in Dependency Problem Solving Tools

Key Commands Comparison

Dependency Resolution & Overrides

Unique Features

npm:

• npm doctor - Diagnoses npm installation issues
• npm ci - Clean install for CI environments

Yarn Classic:

• Global resolutions field
• yarn check --integrity - Verify lockfile

Yarn Berry:

• Constraints engine (.yarn/constraints.pro)
• Resolution protocols (portal:, patch:, exec:)
• PnP prevents phantom dependencies

pnpm:

• Strictest by default (no phantom deps)
• Content-addressable store (pnpm store)
• Peer dependency auto-installation

Common Problems Quick Reference

Version Conflicts:

npm ls package-name      # npm
yarn why package-name    # Yarn
pnpm why package-name    # pnpm

Security Issues:

npm audit fix            # npm
yarn upgrade pkg@ver     # Yarn (manual)
pnpm audit --fix        # pnpm

Phantom Dependencies:

• npm/Yarn Classic: No protection
• Yarn Berry: Use PnP mode
• pnpm: Protected by default

Unique Features and Considerations

Dependency Shadowing & Resolution

Shadowing Problem: When different versions of the same package exist in nested node_modules:

app/node_modules/
├── lodash@4.17.21
└── old-lib/node_modules/
    └── lodash@3.10.1  # Shadow dependency

Resolution Examples:

Force all lodash to specific version:

"overrides": {"lodash": "4.17.21"}

"resolutions": {"**/lodash": "4.17.21"}

"pnpm": {"overrides": {"lodash": "4.17.21"}}

Target specific dependency paths:

"overrides": {"package-a": {"lodash": "3.10.1"}}

"resolutions": {"package-a/lodash": "3.10.1"}

"pnpm": {"overrides": {"package-a>lodash": "3.10.1"}}

Outstanding Features by Package Manager

npm:

• Default with Node.js
• Largest ecosystem
• Workspaces support (v7+)
• Fund command for OSS support

Yarn Classic:

• Yarn.lock for determinism
• Offline mirror
• License checker
• Selective version resolutions

Yarn Berry:

• Plug'n'Play (no node_modules)
• Zero-installs
• Constraints engine
• Protocols (workspace:, portal:, patch:, exec:)
• Built-in patch support
• Plugin architecture

pnpm:

• Content-addressable storage
• Strictest dependency isolation (prevents phantom dependencies by default)
• Fastest for monorepos
• Catalog protocol
• Built-in patching
• Side-effects cache

Strict Installation Comparison

*Configurable

Summary and Recommendations

Recommendations by Use Case

Migration Paths

# npm → pnpm
npx pnpm import
pnpm install

# Yarn Classic → Yarn Berry
yarn set version berry
yarn install

# Any → pnpm (monorepo)
pnpm import
# Create pnpm-workspace.yaml
pnpm install

Migration Complexity Analysis

Migration from npm to pnpm

Complexity Level: Low to Medium

Steps Required:

1. Import existing lockfile: npx pnpm import (converts package-lock.json)
2. Create workspace configuration (for monorepos):

   # pnpm-workspace.yaml
   packages:
     - 'packages/*'
     - 'apps/*'

3. Update CI/CD scripts: Replace npm commands with pnpm
4. Handle peer dependencies: pnpm auto-installs them (may require adjustments)

Key Differences to Address:

Potential Issues:

• Phantom dependencies: Code relying on undeclared dependencies will break
• Different hoisting: Some imports may need explicit declaration
• Shamefully-hoist flag: May be needed for problematic packages
• Node.js version: Requires Node.js 16.14+ for latest pnpm

Migration from npm to Yarn Berry

Complexity Level: Medium to High

Steps Required:

1. Install Yarn Berry: npm install -g yarn && yarn set version berry
2. Configure PnP or node_modules: Choose installation strategy
3. Update editor settings: VSCode/IDE support for PnP
4. Migrate scripts: Update package.json scripts
5. Configure constraints (optional): Define dependency rules

Key Differences to Address:

Configuration Decisions:

# .yarnrc.yml
nodeLinker: pnp # or 'node-modules'
enableGlobalCache: true
enableMirror: true
compressionLevel: mixed

plugins:
  - path: .yarn/plugins/@yarnpkg/plugin-interactive-tools.cjs
    spec: "@yarnpkg/plugin-interactive-tools"

Potential Issues:

• PnP compatibility: Some packages don't work with Plug'n'Play
• Tool integration: Build tools may need configuration updates
• Learning curve: New concepts (protocols, constraints, plugins)
• Bundle size: .yarn folder can be large if committing cache

Migration from Yarn Classic to pnpm

Complexity Level: Low to Medium

Steps Required:

1. Remove Yarn artifacts: rm -rf node_modules yarn.lock
2. Install pnpm: npm install -g pnpm
3. Create workspace config: Convert workspaces to pnpm-workspace.yaml
4. Install dependencies: pnpm install
5. Update scripts: Replace yarn with pnpm in package.json

Key Differences to Address:

Migration Configuration:

# .yarnrc.yml for gradual migration
nodeLinker: node-modules  # Start with familiar structure
enableGlobalCache: true
enableMirror: false

# Gradually enable advanced features
# nodeLinker: pnp
# enableScripts: false
# enableImmutableInstalls: true

Common Migration Challenges

Phantom Dependencies:

# Problem: Code importing undeclared dependencies
import _ from 'lodash' # Not in package.json but works with npm/Yarn

# Solution: Declare all dependencies explicitly
pnpm add lodash

CI/CD Updates:

# GitHub Actions example
- name: Install dependencies
  run: |
    corepack enable
    pnpm install --frozen-lockfile

# or for Yarn Berry
- name: Install dependencies
  run: |
    corepack enable
    yarn install --immutable

Tool Configuration:

TypeScript module resolution for PnP (tsconfig.json):

{
  "compilerOptions": {
    "moduleResolution": "node",
    "types": [
      "node",
      "@types/node"
    ]
  },
  "ts-node": {
    "esm": true
  }
}

Conclusions

Choosing the right package manager is crucial for the efficiency and scalability of your JavaScript projects.

• npm remains the default, simple choice for smaller projects.
• pnpm stands out for its superior performance and disk space efficiency, making it the top recommendation for monorepos and large-scale applications.
• Yarn Classic is best suited for legacy projects, with a clear migration path to more modern tools.
• Yarn Berry offers advanced, cutting-edge features but requires careful consideration of its ecosystem and compatibility.

Ultimately, the best choice depends on your specific needs, team expertise, and project complexity. For new projects, pnpm is a strong contender that can save you time and resources in the long run.

Need Help with Your Project?

Optimizing your development workflow is just one part of building a successful application. If you're looking for expert guidance on anything from monorepo strategy and CI/CD pipelines to front-end architecture and performance, I can help.

Contact me today to discuss your project's unique challenges and how we can solve them together.

References