When you install an npm package using
npm install <package-name>, you are installing it as a dependency.
The package is automatically listed in the package.json file, under the
dependencies list (as of npm 5: before you had to manually specify
When you add the
-D flag, or
--save-dev, you are installing it as a development dependency, which adds it to the
When you go in production, if you type
npm install and the folder contains a
package.json file, they are installed, as npm assumes this is a development deploy.
You need to set the
--production flag (
npm install --production) to avoid installing those development dependencies.
One more thing! ⚠️ ✋
It's a 10-weeks long cohort online course where I will guide you to becoming a Web Developer.
It's not "just a course". It's a big event I organize once a year.
At the end of the first 10 weeks you'll know how to create web sites and web applications and I'll unlock you the 2nd phase of the Bootcamp: you will get access to a large number of projects exclusive to the Bootcamp graduates, so you can follow my instructions to build things like private areas with authentication, clones of popular sites like Twitter YouTube Reddit, create e-commerce sites, and much much more.
Because once you got the fundamentals, you only learn by working on real, exciting projects.
To find out more, visit bootcamp.dev