Choosing the Right Package Manager: npm vs Yarn vs pnpm vs Bun

Every JavaScript project starts with a package manager. It installs your dependencies, locks their versions, runs your build scripts, and — if you're deploying with a tool like DeployHQ — it's the first command that runs in your build pipeline before files reach your server.

But which one should you use? npm, Yarn, pnpm, and Bun each take a different approach to solving the same problem. This guide compares all four with current benchmarks, correct commands, and practical advice for choosing the right one for your project and deployment workflow.

Quick Comparison

npm: The Default

npm ships with every Node.js installation. You don't need to install anything extra — it's just there.

Strengths:

• Zero setup — comes with Node.js
• Largest registry (2.5M+ packages)
• npm audit for security vulnerability scanning
• Deterministic installs via package-lock.json
• Workspaces support since v7

Weaknesses:

• Consistently the slowest in benchmarks
• Copies dependencies into each project's node_modules
• Flat dependency tree can cause phantom dependencies — packages you can import but didn't explicitly install

Common commands:

npm init                        # Create a new project
npm install                     # Install all dependencies
npm install express             # Add a package
npm install -g typescript       # Install globally
npm run build                   # Run a script
npm audit                       # Check for vulnerabilities

When to use npm: Standard Node.js projects where you want the simplest setup with no extra tooling. Good for small projects and teams already comfortable with the npm ecosystem.

Yarn: Classic vs Berry

Yarn has two distinct versions that work very differently:

• Yarn Classic (v1) — the original, now in maintenance mode
• Yarn Berry (v2, v3, v4) — a complete rewrite with Plug'n'Play (PnP)

Modern Yarn (v4) can eliminate node_modules entirely using PnP, which maps dependencies to zip archives. This makes installs near-instant after the first run and enables zero-installs where you commit your dependency cache to Git.

Strengths:

• PnP mode eliminates node_modules and speeds up installs
• Excellent monorepo/workspace support
• Strict dependency resolution prevents phantom dependencies
• Plugins architecture for extensibility

Weaknesses:

• PnP requires editor setup and can have compatibility issues with some packages
• Two incompatible versions cause confusion (Classic vs Berry)
• node_modules mode in Berry can be slower than npm in some benchmarks
• yarn global was removed in Berry — use yarn dlx instead

Common commands (Yarn Berry v4):

yarn init                       # Create a new project
yarn install                    # Install all dependencies
yarn add express                # Add a package
yarn dlx create-react-app       # Run a one-off command (replaces npx)
yarn run build                  # Run a script
yarn audit                      # Check for vulnerabilities

When to use Yarn: Monorepo projects that benefit from PnP's speed and strict dependency isolation. Teams willing to invest in PnP setup for the long-term performance gains.

pnpm: The Disk-Efficient Option

pnpm stores every package version once in a global content-addressable store (~/.pnpm-store) and hard-links them into each project. If ten projects use the same version of Express, it's stored once on disk.

Strengths:

• Saves 50–70% disk space compared to npm
• Faster than npm and Yarn in most benchmarks
• Strict node_modules structure prevents phantom dependencies
• Excellent monorepo support with filtering and recursive commands

Weaknesses:

• Smaller community compared to npm (though growing rapidly)
• Some packages that rely on hoisted node_modules may need configuration
• Hard links can occasionally confuse tools that check file identity

Common commands:

pnpm init                       # Create a new project
pnpm install                    # Install all dependencies
pnpm add express                # Add a package
pnpm add -g typescript          # Install globally
pnpm run build                  # Run a script
pnpm audit                      # Check for vulnerabilities

When to use pnpm: Projects with many dependencies where disk space matters, CI/CD environments where install speed is important, and monorepos. A good upgrade from npm that requires minimal workflow changes.

Bun: The All-in-One Runtime

Bun isn't just a package manager — it's a complete JavaScript/TypeScript runtime built from scratch in Zig. Its package manager is one component of a broader toolkit that includes a bundler, test runner, and native TypeScript execution.

Bun reached v1.0 in September 2023 and is now at v1.3. It's used in production by major companies, including Anthropic (for Claude Code).

Strengths:

• Fastest package manager by a wide margin (~4x faster than pnpm in benchmarks)
• Native TypeScript and JSX support without transpilation
• Built-in bundler and test runner
• Compatible with npm packages and node_modules

Weaknesses:

• Not 100% Node.js API compatible — some edge cases remain
• Smaller ecosystem of Bun-specific tooling
• Requires its own runtime (not a drop-in for Node.js in all cases)
• Lockfile format (bun.lock) differs from npm/Yarn/pnpm

Common commands:

curl -fsSL https://bun.sh/install | bash   # Install Bun
bun init                                     # Create a new project
bun install                                  # Install all dependencies
bun add express                              # Add a package
bun add -g typescript                        # Install globally
bun run build                                # Run a script
bun run index.ts                             # Execute TypeScript directly

When to use Bun: Performance-sensitive projects, TypeScript-first codebases, and teams that want a single tool for runtime + package management + bundling + testing. Particularly strong for development speed.

How Package Manager Choice Affects Deployment

Your choice of package manager directly impacts your deployment pipeline. Here's what matters:

Build commands differ. Whether you run npm ci, yarn install --immutable, pnpm install --frozen-lockfile, or bun install --frozen-lockfile, your deployment tool needs to run the right install command before building. DeployHQ's build pipelines let you configure any shell command, so all four managers work out of the box.

Lockfiles matter. Always commit your lockfile (package-lock.json, yarn.lock, pnpm-lock.yaml, or bun.lock) to Git. This ensures your deployment server installs the exact same dependency versions you tested locally. If you deploy from GitHub or GitLab, DeployHQ picks up the lockfile automatically.

Install speed affects deployment time. Faster installs mean faster deployments. If you're deploying frequently, switching from npm to pnpm or Bun can noticeably reduce your pipeline time.

Installing Each Package Manager

npm ships with Node.js — no extra installation required:

node -v    # Verify Node.js (and npm) is installed
npm -v     # Check npm version

Yarn, pnpm, and Bun can be installed via Corepack (Node.js's built-in package manager manager) or independently:

# Via Corepack (recommended for Yarn and pnpm)
corepack enable
corepack prepare yarn@stable --activate
corepack prepare pnpm@latest --activate

# Or install independently
npm install -g yarn
npm install -g pnpm
curl -fsSL https://bun.sh/install | bash    # Bun has its own installer

FAQ

Q: Can I switch package managers mid-project? A: Yes. Delete your existing lockfile and node_modules, then run install with the new manager. It will generate its own lockfile. Test thoroughly before deploying.

Q: Which is best for CI/CD pipelines? A: pnpm and Bun offer the best install speed for CI environments. Both support frozen lockfile installs. DeployHQ's build pipelines work with all four.

Q: Do I need to install Node.js to use Bun? A: No. Bun is a standalone runtime. However, if your project depends on Node.js-specific APIs, you may still need Node.js installed alongside Bun.

Q: Which package manager does DeployHQ recommend? A: DeployHQ works with all major package managers. Choose based on your project's needs — we'll deploy the result regardless of which tool builds it. See our features page for details.

Q: Is Yarn Classic (v1) still supported? A: Yarn Classic is in maintenance mode and receives only critical fixes. New projects should use Yarn Berry (v4) or consider pnpm as an alternative.

Your package manager handles the foundation of every build. Whether you stick with npm's simplicity, adopt pnpm's efficiency, or go all-in on Bun's speed, the important thing is that your deployment pipeline handles it reliably.

Try DeployHQ free — configure your build pipeline with any package manager and deploy on every push. See pricing for team plans.

Questions? Reach out at support@deployhq.com or @deployhq.