Build is faling when I'm trying to deploy on Heroku - node.js

Question

I'm having trouble getting my application on Heroku, I'm getting the following error, I've already searched around here on Stackoverflow and I've seen responses saying to remove /node_modules and package-lock.json, but unfortunately the error remains.
Output:
-----> Building on the Heroku-20 stack
-----> Determining which buildpack to use for this app
-----> Node.js app detected
-----> Creating runtime environment
NPM_CONFIG_LOGLEVEL=error
NODE_VERBOSE=false
NODE_ENV=production
NODE_MODULES_CACHE=true
-----> Installing binaries
engines.node (package.json): 14.16.1
engines.npm (package.json): unspecified (use default)
Resolving node version 14.16.1...
Downloading and installing node 14.16.1...
Using default npm version: 6.14.12
-----> Installing dependencies
Installing node modules
> nodemon#2.0.15 postinstall /tmp/build_1e107d4a/node_modules/nodemon
> node bin/postinstall || exit 0
Love nodemon? You can now support the project via the open collective:
> https://opencollective.com/nodemon/donate
added 208 packages in 3.879s
-----> Build
Running build
> teste#1.0.0 build /tmp/build_1e107d4a
> concurrently "cd airbnb/ && npm run build"
[0]
[0] > airbnb#0.1.0 build /tmp/build_1e107d4a/airbnb
[0] > react-scripts build
[0]
[0] sh: 1: react-scripts: not found
[0] npm ERR! code ELIFECYCLE
npm ERR! syscall spawn
[0] npm ERR! file sh
npm ERR! errno ENOENT
[0] npm ERR! airbnb#0.1.0 build: `react-scripts build`
[0] npm ERR! spawn ENOENT
[0] npm ERR!
[0] npm ERR! Failed at the airbnb#0.1.0 build script.
[0] npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
[0]
[0] npm ERR! A complete log of this run can be found in:
[0] npm ERR! /tmp/npmcache.ZNegh/_logs/2021-11-16T19_01_58_803Z-debug.log
[0] cd airbnb/ && npm run build exited with code 1
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! teste#1.0.0 build: `concurrently "cd airbnb/ && npm run build"`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the teste#1.0.0 build script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
npm ERR! A complete log of this run can be found in:
npm ERR! /tmp/npmcache.ZNegh/_logs/2021-11-16T19_01_58_824Z-debug.log
-----> Build failed
We're sorry this build is failing! You can troubleshoot common issues here:
https://devcenter.heroku.com/articles/troubleshooting-node-deploys
If you're stuck, please submit a ticket so we can help:
https://help.heroku.com/
Love,
Heroku
! Push rejected, failed to compile Node.js app.
! Push failed

Answer 1

Ok, the problem is with react-script, react-scripts is (by default) a devDependency for CRA apps, but Heroku Node buildpack has environment NODE_ENV=production which causes npm install to skip devDeps.
To install those devDeps too:
npm install --only=dev && npm install && npm run build
additional information.
Please check in your server-side (if you are using it)/add Procfile without any extension in the root directory.
and inside the Procfile add web: node here your main file name, for example, index.js in my case.
Please add your pacacge.js code as well so it helps us to help you better.