How can i compile source code?

Hi,
im pretty new to node.
I need to change some parts of uppy source code, this means i need to compile it from source. How can do it?

I entered directory uppy-master\website, run npm install and then node build-examples.js. But i get error:
✗ error: Cannot find module '@babel/plugin-proposal-class-properties' from 'C:\xampp\htdocs\uppy-master' while parsing file: C:\xampp\htdocs\uppy-master\website\src\examples\i18n\app.es6.

I tried to run npm install @babel/plugin-proposal-class-properties but it didnt helped.

I fugured out that i need to run npm run build in main directory. I work on windows, so it didnt had few commands used in build process, like cat or gzip. Thats i run it using cygwin.

Now there is another problem. When i run build process, it ends up with this:

`> uppy-build@0.0.0 size C:\cygwin64\home\User\uppy-master

echo ‘JS Bundle mingz:’ && cat ./packages/uppy/dist/uppy.min.js | gzip | wc -c
&& echo ‘CSS Bundle mingz:’ && cat ./packages/uppy/dist/uppy.min.css | gzip | w
c -c

‘JS Bundle mingz:’
121220
‘CSS Bundle mingz:’
cat: ./packages/uppy/dist/uppy.min.css: No such file or directory
20`

Hmm, that suggests that the css build failed or did not complete before the size script is run. Could you share the output before that happens as well?