title: How can I use variables in package.json?
body: <p>There is a feature from maven I miss a lot in package.json. In maven .pom file you can define variables in parent project and use them in child project's pom files.</p>
  
  <p>Is there something like this in npm? We are building modular project and I want to define dependency versions centrally and them to be used in respective package.json files.</p>
  
  <p>Thanks</p>