🔍 What is npm?
npm stands for Node Package Manager. It is a tool that helps developers install, share, and manage packages (libraries) for Node.js projects.
- npm is like an app store for Node.js code.
- It allows you to add new features to your project without writing everything from scratch.
- It also makes it easier to update and manage your dependencies.
Example:
// Installing a package
// Run this in the terminal
npm install express
This installs the Express library so you can build web applications faster.
📄 What is package-lock.json?
The package-lock.json file keeps an exact record of the versions of all installed packages and their dependencies.
- It locks the package versions to avoid unexpected changes.
- It ensures that every developer on your team uses the exact same versions.
- It helps in creating consistent builds.
Example snippet from package-lock.json:
{
"name": "my-app",
"version": "1.0.0",
"lockfileVersion": 2,
"dependencies": {
"express": {
"version": "4.17.1",
"resolved": "https://registry.npmjs.org/express/-/express-4.17.1.tgz"
}
}
}
This ensures express will always be installed as version 4.17.1.
⚡ What is npm ci?
The npm ci command is used to install dependencies in a clean, predictable way.
- It deletes the existing node_modules folder before installing.
- It installs exactly what is listed in package-lock.json.
- It is faster than npm install for automated builds and CI/CD pipelines.
Example:
// Using npm ci in a terminal
npm ci
This ensures the dependencies match exactly what is in package-lock.json for stable builds.
📊 npm install vs npm ci
| Feature |
npm install |
npm ci |
| Speed |
Slower |
Faster |
| Uses package-lock |
Yes |
Yes |
| Cleans node_modules |
No |
Yes |
| Predictable builds |
Sometimes |
Always |
📝 Summary
In Node.js projects, npm is the package manager that installs and manages libraries, package-lock.json ensures exact version consistency, and npm ci installs packages in a clean, predictable way ideal for automated environments. Together, they make dependency management faster, more reliable, and easier to maintain.