Created by: cjpatoilo
Dependencies serve many different purposes. Some dependencies are needed to build your project, others are needed when you’re running your program.
devDependencies are the development dependencies. Dependencies that you need at some point in the development workflow but not while running your code (e.g. Flow, TypeScript, Jest or Enzyme).
For me it makes sense to define devDependencies flag to install Jest and Enzyme as development dependencies. On the Enzyme's homepage as well as the Jest's homepage, there are guidance for installing as development dependency btw.