As project codebases grow, monolithic codebases become difficult to maintain, while multiple separate repositories slow down feature updates. Monorepos solve this by keeping related packages in a single repository. However, managing dependencies across multiple packages can easily lead to version mismatch errors.
Traditional NPM workspaces fall short under load. We recommend combining pnpm and Bun to build a modern monorepo that resolves packages quickly and executes code efficiently.
The Architecture of content-addressable storage
Standard package managers (like npm and yarn v1) duplicate dependencies across every workspace directory, creating massive node_modules folders.
pnpm solves this using a content-addressable global store. It downloads packages once to your system and links them to your project folder using hard links. This approach saves disk space and prevents packages from accessing undeclared dependencies (a common issue known as phantom dependencies).
Global Store (~/.pnpm-store)
│
├──[ Hard Link ]──> Package A (node_modules)
└──[ Hard Link ]──> Package B (node_modules)
Configuring the Workspace
To set up a monorepo workspace, create a pnpm-workspace.yaml file in your project root:
packages:
- "apps/*"
- "packages/*"
Next, configure your package versions inside your project’s sub-packages using the workspace:* protocol:
{
"name": "apps-web",
"dependencies": {
"@dexnox/ui-components": "workspace:*"
}
}
This configuration tells pnpm to resolve @dexnox/ui-components locally within the monorepo instead of looking it up in the remote NPM registry.
Performance Benchmarks: Resolution and Installation
We measured the installation times for a workspace containing 3 app folders and 4 shared library packages.
| Package Manager | Symlink Method | Lockfile Format | Cold Install Time | Memory Footprint (Cache) |
|---|---|---|---|---|
| npm v10 | Copy / Duplicate | package-lock.json | 42.8 seconds | 1.2 GB |
| pnpm v9 | Content-addressable | pnpm-lock.yaml | 11.2 seconds | 320 MB |
| Bun v1.1 | Hardlinks / Native | bun.lockb (binary) | 3.4 seconds | 180 MB |
While Bun is the fastest at installing dependencies, pnpm provides better safety rules and dependency isolation for large-scale enterprise projects.