Minify JSON file containing some data

In my Sage theme I created a data folder in resources/assets/ with two JSON file. They contain data, what my theme uses.
I modified the resources/assets/build/config.js file, to copy the data folder with the images folder:

const config = merge({
  open: true,
  copy: '+(images|data)/**/*',

It’s works great, but I wish to minify my .json files. The original files are nicely indented, but they are half the size if I remove spaces and newlines manually.
Any suggestions, how to do it programatically?
P.s.: I never used webpack before.

Also notice that gzipping can even further, and possible even far better, reduce the actual size of the file.