ElasticBeanstalk - Container Command Webpack Build Error

Question

I am trying to migrate my webpack build command from having to be run before pushing to a repo and deploying to my server to having an elasticbeanstalk extension run a container command. I thought simply added an eb extension with npm run build would generate this without any issue like it does in the local environment, but I receive the following error:

 Command execution failed: Activity failed. (ElasticBeanstalk::ActivityFatalError)
caused by: 
  > app@0.5.0 build /tmp/deployment/application
  > webpack


  npm ERR! Linux 4.14.47-56.37.amzn1.x86_64
  npm ERR! argv "/opt/elasticbeanstalk/node-install/node-v6.14.3-linux-x64/bin/node" "/bin/npm" "run" "build"
  npm ERR! node v6.14.3
  npm ERR! npm  v3.10.10
  npm ERR! file sh
  npm ERR! path sh
  npm ERR! code ELIFECYCLE
  npm ERR! errno ENOENT
  npm ERR! syscall spawn sh
  npm ERR! app@0.5.0 build: `webpack`
  npm ERR! spawn sh ENOENT
  npm ERR!
  npm ERR! Failed at the app@0.5.0 build script 'webpack'.
  npm ERR! Make sure you have the latest version of node.js and npm installed.
  npm ERR! If you do, this is most likely a problem with the app package,
  npm ERR! not with npm itself.
  npm ERR! Tell the author that this fails on your system:
  npm ERR!     webpack
  npm ERR! You can get information on how to open an issue for this project with:
  npm ERR!     npm bugs app
  npm ERR! Or if that isn't available, you can get their info via:
  npm ERR!     npm owner ls app
  npm ERR! There is likely additional logging output above.
  npm ERR! Linux 4.14.47-56.37.amzn1.x86_64
  npm ERR! argv "/opt/elasticbeanstalk/node-install/node-v6.14.3-linux-x64/bin/node" "/bin/npm" "run" "build"
  npm ERR! node v6.14.3
  npm ERR! npm  v3.10.10
  npm ERR! code ELIFECYCLE

here is the elastic beanstalk configuration file:

container_commands:
  00_npm_build:
    command: "sudo npm run build"

the config.json script section:

 "main": "app.js",
  "scripts": {
    "start": "node app.js",
    "build": "webpack",
    "test": "echo \"Error: no test specified\" && exit 1",
    "sql": "./node_modules/sequelize-cli/lib/sequelize",
    "sql:migrate": "npm run sql db:migrate"
  },

and the webpack config:

module.exports = {
    entry: "./public/index.js",
    output: {
        path: __dirname + "/dist",
        filename: "bundle.js"
    },
    module: {
        loaders: [
            {   
                test: /\.js$/, 
                exclude: /node_modules/, 
                loader: "babel-loader"
            },
            {   
                test: /\.jsx$/, 
                exclude: /node_modules/, 
                loader: "babel-loader"
            }
        ]
    },
};

Answer 1

None on these worked, I simply did:

-in EBS config I set Node command to npm start

-in package.json:

"scripts": {
  ...

  "start": "npx sequelize-cli db:migrate && node index.js"
},