maintain build version number in package.json file code example

Example 1: npm version notation

1.2.3 => 1.2.3 (Matching exactly same version)
~1.2.3 => >=1.2.3 && < 1.3.0 (Matching minor version)
^1.2.3 => >=1.2.3 && < 2.0.0 (Matching major version)

Example 2: npm package at version

npm install <package>@<version>