How can i compile source code?

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

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?