.TH "NPM\-CI" "1" "August 2018" "" "" .SH "NAME" \fBnpm-ci\fR \- Install a project with a clean slate .SH SYNOPSIS .P .RS 2 .nf npm ci .fi .RE .SH EXAMPLE .P Make sure you have a package\-lock and an up\-to\-date install: .P .RS 2 .nf $ cd \./my/npm/project $ npm install added 154 packages in 10s $ ls | grep package\-lock .fi .RE .P Run \fBnpm ci\fP in that project .P .RS 2 .nf $ npm ci added 154 packages in 5s .fi .RE .P Configure Travis to build using \fBnpm ci\fP instead of \fBnpm install\fP: .P .RS 2 .nf # \.travis\.yml install: \- npm ci # keep the npm cache around to speed up installs cache: directories: \- "$HOME/\.npm" .fi .RE .SH DESCRIPTION .P This command is similar to npm help \fBnpm\-install\fP, except it's meant to be used in automated environments such as test platforms, continuous integration, and deployment\. 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\. .P In short, the main differences between using \fBnpm install\fP and \fBnpm ci\fP are: .RS 0 .IP \(bu 2 The project \fBmust\fR have an existing \fBpackage\-lock\.json\fP or \fBnpm\-shrinkwrap\.json\fP\|\. .IP \(bu 2 If dependencies in the package lock do not match those in \fBpackage\.json\fP, \fBnpm ci\fP will exit with an error, instead of updating the package lock\. .IP \(bu 2 \fBnpm ci\fP can only install entire projects at a time: individual dependencies cannot be added with this command\. .IP \(bu 2 If a \fBnode_modules\fP is already present, it will be automatically removed before \fBnpm ci\fP begins its install\. .IP \(bu 2 It will never write to \fBpackage\.json\fP or any of the package\-locks: installs are essentially frozen\. .RE .SH SEE ALSO .RS 0 .IP \(bu 2 npm help install .IP \(bu 2 npm help 5 package\-locks .RE