fixes #7

gatsby-config.js

@@ -46,6 +46,14 @@ module.exports = {
       resolve: `gatsby-plugin-netlify-cms`,
       options: {
         modulePath: `${__dirname}/src/cms/cms.js`, // for custom preview in the Netlify CMS
+        customizeWebpackConfig: config => {
+          config.node = {
+            ...config.node,
+            fs: "empty",
+            child_process: "empty",
+            module: "empty",
+          };
+        },
       },
     },
   ],

gatsby-node.js

@@ -5,3 +5,13 @@
  */
 
 // You can delete this file if you're not using it
+
+
+// gatsby-node.js
+exports.onCreateWebpackConfig = ({ actions }) => {
+  actions.setWebpackConfig({
+    node: {
+      fs: 'empty'
+    }
+  })
+}