Trying a different approach hosting on heroku with node

.gitignore

@@ -24,7 +24,6 @@ hs_err_pid*
 
 .gradle
 .classpath
-#/build
 bin
 
 # dependencies
@@ -34,7 +33,7 @@ bin
 /coverage
 
 # production
-#/build
+/build
 
 # misc
 .DS_Store

package.json

@@ -0,0 +1,31 @@
+{
+  "name": "heroku-cra-node",
+  "version": "1.0.0",
+  "description": "How to use create-react-app with a custom Node API on Heroku",
+  "engines": {
+    "node": "8.9.x"
+  },
+  "scripts": {
+    "start": "node server",
+    "heroku-postbuild": "cd JSVisualizer/ && npm install && npm install --only=dev --no-shrinkwrap && npm run build"
+  },
+  "cacheDirectories": [
+    "node_modules",
+    "JSVisualizer/node_modules"
+  ],
+  "dependencies": {
+    "express": "^4.16.3"
+  },
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/Team488/SimpleVisualizer.git"
+  },
+  "keywords": [
+    "node",
+    "heroku",
+    "create-react-app",
+    "react"
+  ],
+  "license": "MIT",
+  "devDependencies": {}
+}

server/index.js

@@ -0,0 +1,41 @@
+const express = require('express');
+const path = require('path');
+const cluster = require('cluster');
+const numCPUs = require('os').cpus().length;
+
+const PORT = process.env.PORT || 5000;
+
+// Multi-process to utilize all CPU cores.
+if (cluster.isMaster) {
+  console.error(`Node cluster master ${process.pid} is running`);
+
+  // Fork workers.
+  for (let i = 0; i < numCPUs; i++) {
+    cluster.fork();
+  }
+
+  cluster.on('exit', (worker, code, signal) => {
+    console.error(`Node cluster worker ${worker.process.pid} exited: code ${code}, signal ${signal}`);
+  });
+
+} else {
+  const app = express();
+
+  // Priority serve any static files.
+  app.use(express.static(path.resolve(__dirname, '../JSVisualizer/build')));
+
+  // Answer API requests.
+  app.get('/api', function (req, res) {
+    res.set('Content-Type', 'application/json');
+    res.send('{"message":"Hello from the custom server!"}');
+  });
+
+  // All remaining requests return the React app, so it can handle routing.
+  app.get('*', function(request, response) {
+    response.sendFile(path.resolve(__dirname, '../JSVisualizer/build', 'index.html'));
+  });
+
+  app.listen(PORT, function () {
+    console.error(`Node cluster worker ${process.pid}: listening on port ${PORT}`);
+  });
+}