Cache npm dependencies?

[Andonvr]

I'm writing a package in deno, transform it using dnt, and use it in a react app. I wrote a small script that listens to file changes and runs dnt on change.
Now, I noticed that the dependencies are being installed anew every time, even when they don't change. Is there a way to cache this?

In my case, it actually accumulates over multiple cross dependent deno packages, all being built.