You'll need two terminal windows open - one to run the React compilation toolchain, and another to run Django to actually serve the site.

# In terminal one
./manage.py runserver

# In terminal two
npm run start

If you push this directly to a new app on Heroku, it will fail, because the Python buildpack will try to run before the Node buildpack. After creating the new application:

1. Add the Node buildpack
2. Add the Python buildpack
3. Set the DJANGO_DEBUG environment variable to False

Then push your project via git push heroku master. It should download NPM and install your dependencies for you.

Once it finishes that, it will download Python and do the typical Django build process. Unfortunately the bin/post_compile script runs after the collectstatic step, so we call python manage.py collectstatic again after we generate the compiled React code.

Once you've done that, it should be running.