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The End of npm? pnpm & Bun Explained

Introduction

For more than a decade, npm has been the default package manager for JavaScript projects. Almost every frontend or backend project—React, Angular, Node.js, or even tooling scripts—started with npm install. It became so common that many developers never questioned it.

But things are changing.

In 2025, more teams are asking a serious question:

Is npm still the right choice for modern applications, or is it time to move on?

Two strong alternatives have gained massive adoption:

  • pnpm, a faster and more disk-efficient package manager

  • Bun, an all-in-one JavaScript runtime with a built-in package manager

This article explains:

  • Why npm is losing ground

  • How pnpm works internally

  • What Bun brings to the table

  • Real Angular project comparisons

  • Which tool makes sense for production in 2025

This is not hype-driven content. It is based on real-world usage, CI pipelines, enterprise Angular apps, and long-term maintenance concerns.

Why Package Managers Matter More Than Ever

In the early days, package managers were just tools to download libraries. Today, they are core infrastructure.

A package manager affects:

  • Build speed

  • CI/CD time

  • Disk usage

  • Dependency correctness

  • Security

  • Developer productivity

For large Angular applications with:

  • Hundreds of dependencies

  • Micro-frontends

  • Shared internal libraries

  • Monorepos

…the choice of package manager can easily save or waste hours every week.

npm: The Default That Became a Bottleneck

npm deserves respect. It solved a massive problem and enabled the JavaScript ecosystem to grow. But over time, some serious limitations became visible.

1. Slow Install Times

Even today, many teams face:

  • npm install taking several minutes

  • Repeated installs across projects

  • CI pipelines slowed down by dependency installs

For Angular enterprise apps, this pain multiplies because:

  • Angular CLI has many dependencies

  • RxJS, build tools, testing libraries add weight

  • Monorepos amplify the problem

2. Massive node_modules Size

npm installs duplicate dependencies across projects.

Example:

  • Project A depends on lodash

  • Project B depends on lodash

  • npm installs lodash twice

On a developer machine, this quickly becomes:

  • 5–10 GB of node_modules

  • Slower file system operations

  • Issues on Windows machines

3. Flat Dependency Hoisting Problems

npm flattens dependencies aggressively. This leads to:

  • Hidden dependency access

  • Code accidentally importing packages not listed in package.json

  • Bugs appearing only in CI or production

Angular apps are especially sensitive because:

  • Build tooling expects strict dependency graphs

  • Hidden dependencies can break builds during upgrades

4. Lockfile Instability (Historically)

Although npm has improved, many teams still remember:

  • Lockfile changes without reason

  • Different installs across machines

  • “Works on my machine” issues

Enter pnpm: A Smarter Package Manager

pnpm is not a new tool, but in recent years it has gone from “interesting alternative” to enterprise-ready standard.

Core Idea of pnpm

pnpm uses a content-addressable store.

Instead of copying dependencies into every project:

  • Packages are stored once globally

  • Projects link to them using hard links or symlinks

This single idea changes everything.

How pnpm Works Internally

Global Store

pnpm keeps a global store like:

~/.pnpm-store/

Each package version exists only once.

If 20 Angular projects depend on:

@angular/[email protected]

It is stored once and shared.

Strict Dependency Resolution

pnpm enforces true dependency isolation.

A package can only access:

  • Its own dependencies

  • Explicitly declared dependencies

This prevents accidental imports.

For Angular, this is extremely valuable because:

  • Build tools stay predictable

  • Library boundaries are respected

  • Upgrades are safer

pnpm vs npm: Real Angular Project Comparison

Let’s consider a real Angular enterprise app:

  • Angular 17

  • Nx monorepo

  • 5 applications

  • 12 shared libraries

npm Experience

  • npm install: ~4–6 minutes

  • node_modules size: ~4.5 GB

  • CI pipeline dependency step: slow

  • Occasional dependency resolution issues

pnpm Experience

  • pnpm install: ~1–2 minutes

  • node_modules size: ~900 MB

  • CI pipeline much faster

  • Fewer hidden dependency bugs

This is not theoretical. Many teams report similar numbers.

Using pnpm with Angular (Step-by-Step)

1. Install pnpm

npm install -g pnpm

2. Create Angular App with pnpm

pnpm create @angular/app my-app
cd my-app
pnpm install

Angular CLI works without issues.

3. pnpm Configuration for Angular

Add .npmrc:

strict-peer-dependencies=trueauto-install-peers=true

This ensures:

  • Peer dependency warnings are handled

  • Angular packages stay aligned

4. Using pnpm in Monorepos

pnpm shines in monorepos.

Example pnpm-workspace.yaml:

packages:- apps/*- libs/*

Angular + Nx + pnpm is now a common enterprise stack.

pnpm in CI/CD Pipelines

pnpm dramatically improves CI performance.

Example GitHub Actions step:

- uses: pnpm/action-setup@v3with:
    version: 9

- run: pnpm install --frozen-lockfile

Benefits:

  • Faster builds

  • Less network usage

  • Deterministic installs

Bun: More Than a Package Manager

Bun is not just competing with npm or pnpm.
It is trying to replace Node.js tooling entirely.

Bun includes:

  • JavaScript runtime

  • Package manager

  • Bundler

  • Test runner

All in one binary.

Why Bun Exists

The JavaScript ecosystem has become complex:

  • Node.js runtime

  • npm or pnpm

  • Webpack or Vite

  • Jest or Vitest

Bun’s goal is simple:

Make JavaScript tooling fast, simple, and integrated.

Bun Package Manager Basics

Using Bun feels familiar:

bun install
bun add rxjs
bun remove lodash

But internally, Bun is written in Zig, not JavaScript.
This gives it huge performance advantages.

Bun Performance: Reality Check

Installation Speed

In many benchmarks:

  • Bun installs dependencies 2–5x faster than npm

  • Often faster than pnpm for cold installs

Disk Usage

Bun uses caching and deduplication but:

  • Not as mature as pnpm’s store

  • Disk usage is reasonable but less predictable

Using Bun with Angular (Current State in 2025)

This is where things get interesting.

Can You Use Bun with Angular?

Yes, but with caveats.

bun install
bun run ng serve

Most Angular projects work, but…

Angular CLI Compatibility

Angular CLI:

  • Still assumes Node.js environment

  • Some scripts expect Node APIs

  • Bun supports many Node APIs, but not all

In real projects:

  • 80–90% works fine

  • Edge cases appear in custom builders or plugins

Bun as a Runtime vs Node.js

Bun is fast, but Node.js is battle-tested.

For Angular:

  • Development tooling still expects Node

  • SSR with Angular Universal is more stable on Node

  • Enterprise teams value stability over raw speed

As of 2025:

  • Bun is promising

  • Node.js remains safer for production Angular backends

Bun in CI/CD: Is It Ready?

Bun can significantly reduce pipeline time.

But enterprises face concerns:

  • Smaller ecosystem

  • Fewer long-term support guarantees

  • Less tooling maturity

Many teams adopt Bun locally, but keep Node.js in CI.

pnpm vs Bun: Feature Comparison

FeaturepnpmBun
Package ManagerYesYes
RuntimeNoYes
Disk EfficiencyExcellentGood
Angular CompatibilityExcellentPartial
Monorepo SupportExcellentImproving
CI StabilityProvenEmerging
EcosystemMatureGrowing

Is npm Really Ending?

Short answer: No
Practical answer: It is no longer the best default

npm will continue to exist because:

  • It is bundled with Node.js

  • It is deeply embedded in tooling

  • Millions of projects depend on it

But for new projects, npm is increasingly avoided.

What Senior Developers Are Choosing in 2025

Typical Enterprise Angular Stack

  • Node.js LTS

  • pnpm

  • Angular CLI

  • Nx or standalone monorepo

  • Docker + CI/CD

Experimental / High-Performance Teams

  • Bun (local development)

  • pnpm fallback

  • Node.js for production

Migration Strategy: npm → pnpm

Step 1: Replace Lockfile

rm package-lock.json
pnpm install

Step 2: Fix Hidden Dependencies

pnpm will expose:

  • Missing dependencies

  • Incorrect imports

Fix them properly.

Step 3: Update CI

Replace npm install with pnpm install.

Migration Strategy: npm → Bun

Proceed carefully.

Recommended only if:

  • You control most tooling

  • You have strong test coverage

  • You accept early-adopter risk

Common Mistakes to Avoid

  1. Blindly switching without CI testing

  2. Mixing npm and pnpm lockfiles

  3. Using Bun in production without fallback

  4. Ignoring peer dependency warnings

Long-Term Outlook (2025–2027)

  • pnpm will become default in more frameworks

  • Bun will mature rapidly

  • npm will remain, but mostly for legacy workflows

Angular ecosystem trends strongly favour pnpm.

Final Verdict

So, is this the end of npm?

Not officially—but functionally, yes for many teams.

  • pnpm is the safest, most efficient choice for Angular in 2025

  • Bun is exciting and fast, but still maturing

  • npm is stable but increasingly outdated for large-scale apps

If you are starting a new Angular project today, pnpm should be your default choice.
If you want to experiment and push performance limits, explore Bun carefully.

The future of JavaScript tooling is faster, stricter, and more intentional—and npm is no longer leading that future.