Nginx unable to override to set root

[CyberMew]

I am using Hugo and it generates static html pages via hugo command. I used https://github.com/testdouble/heroku-buildpack-hugo for this. In the deployed app, my repo files are stored in the path /app/www, and the buildpack generates the public folder (and files) at /app/www/public. Nginx is currently display all files inside /app/www (directory listing), which is obviously not the public folder, but for some reason no matter what I configure, it just doesn't want to load /app/www/public instead.

I tried config:set my app NGINX_ROOT=/app/www/public or NGINX_ROOT=public but nothing happens. I tried adding it to .env file as well as some combination of those to no avail. I also tried copy pasting the template for nginx.conf.sigil into my repo and it seems to pull from there, but it still doesn't work for some reason. I even hardcoded root /app/www/public; in the servers portion of the nginx.conf.sigil file yet it has no effect.

Kinda new to all this, seems like I am missing some understanding here, any help is appreciated.

[CyberMew]

I found out that I have to add a second buildpack for nginx after the custom buildpack, then with the config:set to public and not /app/www/public (found this via reading the app sigil), it will work and there is no need to add anything more to the .env or create a .sigil config. This helped me as well https://ericmjl.github.io/essays-on-data-science/miscellaneous/static-sites-on-dokku/#build-a-static-site-skip-if-you-already-have-one