Most of my plugins are installed as Dev Dependencies in package.json.
<https://medium.com/@dylanavery720/npmmmm-1-dev-dependencies-dependencies-8931c2583b0c>

But I still don't quite understand why and what would go in dependency vs dev dependency.
If I was modifying the cypress core would I install as a dependency? OR if I had a real app mixed (example Node + React) mixed with the same package.json?