Deploying Vue.js + Express + MongoDB App to Heroku

Question

So I've been at this for two days now and can't figure it out. I'm trying to deploy a Vue front end and express back end app to Heroku.

In my root folder I have a "public" folder which contains the front end and "server" folder for the back end.

In the root directory's package.json, the start script is

    "start": "npm run pull && start npm run f && start npm run b",
    "pull": "git pull",
    "f": "cd ./public && npm run serve",
    "b": "cd ./server && npm run dev"

This works perfectly fine for me to run locally, and even works with heroku locally as well using heroku local web but when I try to actually push to heroku using git push heroku main it doesn't even get past the git pull claiming:

fatal: not a git repository (or any parent up to mount point /)

I've tried simply getting rid of the git pull, but that just leads down a rabbit hole of other errors I've been trying to figure out for days and I'm hoping I'm just being dumb and missing something obvious. Any help would be greatly appreciated.

I'm going to try and list some things I've tried here:

1. Setting the heroku remote repository heroku git:remote -a heroku-name-here
   • Didn't change anything, pretty sure I already have this correct
2. Removing the git pull
   • Led to heroku not recognizing "start" sh: 1: start: not found
3. Removing the 'start' after git pull
   • Led to vue-cli-service not being found
4. Literally separating the back and front end into 2 separate repositories and 2 separate heroku things
   • This seemed to get the back end functioning, but the front end didn't seem to work. Unfortunately I don't remember exactly why but can try again if it would be helpful
5. All 3 comments from here: How to solve vue-cli-service: not found proplem on heroku?