remove react-scripts, change build commands

package.json

@@ -27,13 +27,12 @@
     "react-feather": "^1.1.6",
     "react-helmet": "^5.2.1",
     "react-router-dom": "^5.0.0",
-    "react-scripts": "2.1.8",
     "react-spinners": "^0.5.3",
     "recompose": "^0.30.0"
   },
   "scripts": {
-    "start": "react-scripts start",
-    "build": "react-scripts build",
+    "start": "gatsby develop",
+    "build": "gatsby build",
     "test": "react-scripts test",
     "eject": "react-scripts eject"
   },