Shanu

Posted on Aug 21

Why Use NPM When PNPM Does It Better?

#npm #pnpm #webdev #node

In the modern web development landscape, efficiency and speed are key. Managing dependencies effectively can make a significant difference in the performance and maintainability of your projects. While npm and yarn have been the go-to tools for years, there’s a new contender that’s quickly gaining popularity among developers—PNPM. In this article, we’ll take a deep dive into PNPM, exploring what makes it stand out, how it works under the hood, and why it might be the best choice for your next project.

What is PNPM?**

PNPM, short for Performant NPM, is a modern package manager for Node.js that offers a unique approach to managing dependencies. It was created to address the inefficiencies found in traditional package managers like npm and yarn, particularly in how they handle disk space and speed.

Why PNPM Was Created:

Traditional Package Managers’ Limitations:
- npm and yarn install dependencies in a flat node_modules directory, often leading to redundant copies of the same packages across multiple projects. This approach consumes unnecessary disk space and can slow down installations, especially in large projects or monorepos.
- Dependency resolution in these traditional managers can sometimes lead to conflicts or issues, especially in complex projects with multiple sub-dependencies.
PNPM’s Solution:
- Global Content-Addressable Storage: PNPM stores packages in a global directory and creates hard links to them in your project’s node_modules folder. This means that multiple projects can share the same package version without duplication, drastically reducing disk space usage.
- Speed: By leveraging this unique storage mechanism, PNPM can install dependencies faster, particularly in monorepos where multiple projects rely on the same dependencies.

How PNPM Works Under the Hood**

Understanding how PNPM handles dependencies can help you appreciate its benefits even more. Let’s break down the key mechanisms that make PNPM so efficient.

Content-Addressable Storage:

Global Store: When you install a package with PNPM, it doesn’t just place the files directly into your project’s node_modules folder. Instead, it first stores them in a global store located in your system’s .pnpm-store directory.
Hard Links: PNPM then creates hard links from your project’s node_modules directory to the files in the global store. These hard links are pointers to the actual files, meaning multiple projects can reference the same files without duplication.
Integrity and Consistency: This method ensures that your dependencies are consistent across projects while minimizing redundancy.

Strict Dependency Resolution:

Non-Flat Node Modules: Unlike npm and yarn, PNPM does not flatten the node_modules directory. Instead, it strictly adheres to the package hierarchy, reducing the chances of dependency conflicts.
Lockfiles: PNPM uses a pnpm-lock.yaml file to lock dependencies, ensuring consistent installs across different environments and machines.

Workspaces and Monorepos:

Built-In Workspace Support: PNPM’s workspace feature allows you to manage multiple projects within a monorepo easily. Dependencies are shared across projects, and you can run scripts or install packages at the root level or within individual packages.
Efficient Development: In a monorepo setup, PNPM’s speed and disk efficiency shine, as it can quickly install shared dependencies without redundancy.

Why Choose PNPM?**

Now that we’ve explored how PNPM works, let’s discuss why you might choose PNPM over other package managers.

Disk Space Efficiency:

No Redundant Copies: By using hard links and a global store, PNPM avoids the common issue of redundant copies of dependencies across projects. This can save gigabytes of disk space, particularly in large projects or monorepos.

Speed:

Faster Installations: PNPM’s unique approach to storage and linking results in faster installations, especially when working with large dependency trees or shared dependencies across projects.

Strict and Predictable Dependency Management:

Avoiding Dependency Conflicts: PNPM’s non-flat node_modules structure helps prevent the infamous "dependency hell" where conflicting dependencies can break your build.
Consistency Across Projects: The pnpm-lock.yaml file ensures that your project installs the exact same versions of dependencies across different environments, making builds more predictable.

Workspaces for Monorepos:

Simplified Management: PNPM’s built-in workspace support makes it easier to manage multiple projects in a monorepo, allowing for efficient sharing of dependencies and streamlined development workflows.

Getting Started with PNPM**

Ready to dive in and start using PNPM? Here’s a step-by-step guide to get you up and running.

Installation:

Install PNPM Globally:
- You can install PNPM globally on your system using npm:
```
 npm install -g pnpm
```
Initialize Your Project:
- If you’re starting a new project, simply navigate to your project directory and run:
```
 pnpm init
```
Install Dependencies:
- To install a package, use the pnpm add command:
```
 pnpm add <package-name>
```
Running Scripts:
- PNPM uses the same package.json scripts as npm. You can run them with:
```
 pnpm run <script-name>
```

Using Workspaces:

Setting Up a Monorepo:
- In a monorepo, you can manage multiple projects with a single pnpm-workspace.yaml file at the root of your repository. This file defines which directories should be treated as part of the workspace.
- Example of a pnpm-workspace.yaml file:
```
packages:
  - 'packages/*'
  - 'apps/*'
```

Advanced PNPM Features**

Beyond basic usage, PNPM offers several advanced features that can further enhance your development workflow.

Peer Dependencies Handling:

PNPM allows you to specify peer dependencies in a way that avoids common issues, ensuring that the correct versions are installed.

Custom Package Registries:

PNPM can be configured to use custom package registries, making it suitable for enterprise environments where dependencies are hosted internally.

Recursive Commands:

You can run commands across all projects in a workspace with a single command. For example:

  pnpm recursive install

Publishing Packages:

If you’re working on a package that you plan to publish, PNPM provides tools to streamline the publishing process while maintaining consistency across versions.

6. Conclusion:

PNPM is more than just a faster alternative to npm or yarn; it’s a powerful tool that can transform how you manage dependencies in your projects. Whether you’re working on a small application or managing a complex monorepo, PNPM’s efficiency, speed, and strict dependency management can help you build more reliable, maintainable software. By understanding how PNPM works and incorporating it into your workflow, you can take your development process to the next level.

Call to Action:

Ready to give PNPM a try? Start by installing it in your next project and experience the difference. If you found this guide helpful, stay tuned for more deep dives into modern development tools that can enhance your workflow!

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