NPM-CI(1)

NAME
npm-ci - Install a project with a clean slate

  Synopsis

    npm ci

  Example

Make sure you have a package-lock and an up-to-date install:

    $ cd ./my/npm/project
    $ npm install
    added 154 packages in 10s
    $ ls | grep package-lock

Run npm ci in that project

    $ npm ci
    added 154 packages in 5s

Configure Travis to build using npm ci instead of npm install:

    # .travis.yml
    install:
    - npm ci
    # keep the npm cache around to speed up installs
    cache:
      directories:
      - "$HOME/.npm"

  Description

This command is similar to npm help install, except it's meant to be used in automated environments such as test platforms, continuous integration, and deployment -- or any situation where you want to make sure you're doing a clean install of your dependencies. It can be significantly faster than a regular npm install by skipping certain user-oriented features. It is also more strict than a regular install, which can help catch errors or inconsistencies caused by the incrementally-installed local environments of most npm users.

In short, the main differences between using npm install and npm ci are:

    •   The project must have an existing package-lock.json or npm-shrinkwrap.json.

    •   If dependencies in the package lock do not match those in package.json, npm ci will exit with an error, instead of updating the package lock.

    •   npm ci can only install entire projects at a time: individual dependencies cannot be added with this command.

    •   If a node_modules is already present, it will be automatically removed before npm ci begins its install.

    •   It will never write to package.json or any of the package-locks: installs are essentially frozen.

  See Also

    •   npm help install

    •   npm help package-locks