You can define scripts that can be executed or are triggered before or after another script.

{
  "scripts": {
    "pretest": "scripts/pretest.js",
    "test": "scripts/test.js",
    "posttest": "scripts/posttest.js"
  }
}

In this case, you can execute the script by running either of these commands:

$ npm run-script test
$ npm run test
$ npm test
$ npm t

Pre-defined scripts

Script Name | Description | —— | —— | prepublish | Run before the package is published. | publish, postpublish | Run after the package is published. | preinstall | Run before the package is installed. | install, postinstall | Run after the package is installed. | preuninstall, uninstall | Run before the package is uninstalled. | postuninstall | Run after the package is uninstalled. | preversion, version | Run before bump the package version. | postversion | Run after bump the package version. | pretest, test, posttest | Run by the npm test command | prestop, stop, poststop | Run by the npm stop command | prestart, start, poststart | Run by the npm start command | prerestart, restart, postrestart | Run by the npm restart command |

User-defined scripts

You can also define your own scripts the same way you do with the pre-defined scripts:

{
  "scripts": {
    "preci": "scripts/preci.js",
    "ci": "scripts/ci.js",
    "postci": "scripts/postci.js"
  }
}

In this case, you can execute the script by running either of these commands:

$ npm run-script ci
$ npm run ci

User-defined scripts also supports pre and post scripts, as shown in the example above.