diff --git a/lib/commands/start.js b/lib/commands/start.js
index a95d15d050..bc4a350520 100644
--- a/lib/commands/start.js
+++ b/lib/commands/start.js
@@ -39,7 +39,7 @@ module.exports = async function start(siteDir, cliOptions = {}) {
         console.error(chalk.red(err.stack));
       });
     };
-    const docsRelativeDir = props.siteConfig.customDocsPath || 'docs';
+    const docsRelativeDir = props.siteConfig.customDocsPath;
     const fsWatcher = chokidar.watch(
       [`../${docsRelativeDir}/**/*.md`, 'blog/**/*.md', 'siteConfig.js'],
       {
diff --git a/lib/core/App.js b/lib/core/App.js
index 3302a86ec3..c2970e4d3f 100644
--- a/lib/core/App.js
+++ b/lib/core/App.js
@@ -3,7 +3,7 @@ import {renderRoutes} from 'react-router-config';
 import routes from '@generated/routes'; // eslint-disable-line
 import docsMetadata from '@generated/docsMetadata'; // eslint-disable-line
 import pagesMetadata from '@generated/pagesMetadata'; // eslint-disable-line
-import siteConfig from '@site/siteConfig'; //eslint-disable-line
+import siteConfig from '@generated/siteConfig'; //eslint-disable-line
 
 export default () =>
   renderRoutes(routes, {docsMetadata, pagesMetadata, siteConfig});
diff --git a/lib/load/config.js b/lib/load/config.js
index 1ef863e889..890b92ddfb 100644
--- a/lib/load/config.js
+++ b/lib/load/config.js
@@ -35,6 +35,17 @@ module.exports = function loadConfig(siteDir, deleteCache = true) {
     );
   }
 
+  /* Fill default value */
+  const defaultConfig = {
+    customDocsPath: 'docs',
+    docsUrl: 'docs'
+  };
+  Object.keys(defaultConfig).forEach(field => {
+    if (!config[field]) {
+      config[field] = defaultConfig[field];
+    }
+  });
+
   /* 
     User's own array of custom fields, 
     e.g: if they want to include some field so they can access it later from `props.siteConfig`
diff --git a/lib/load/docs/metadata.js b/lib/load/docs/metadata.js
index 165f343140..a3e1d9bb46 100644
--- a/lib/load/docs/metadata.js
+++ b/lib/load/docs/metadata.js
@@ -118,7 +118,7 @@ module.exports = async function processMetadata(
   }
 
   /* Build the permalink */
-  const {baseUrl, docsUrl = 'docs'} = siteConfig;
+  const {baseUrl, docsUrl} = siteConfig;
 
   /* 
     if user has own custom permalink defined in frontmatter
diff --git a/lib/load/index.js b/lib/load/index.js
index e7c91d005f..691e1a1232 100644
--- a/lib/load/index.js
+++ b/lib/load/index.js
@@ -10,23 +10,23 @@ const genRoutesConfig = require('./routes');
 module.exports = async function load(siteDir) {
   // @tested - siteConfig
   const siteConfig = loadConfig(siteDir);
+  await generate(
+    'siteConfig.js',
+    `export default ${JSON.stringify(siteConfig, null, 2)};`
+  );
 
   // @tested - env
   const env = loadEnv({siteDir, siteConfig});
 
   // docs
-  const docsDir = path.resolve(
-    siteDir,
-    '..',
-    siteConfig.customDocsPath || 'docs'
-  );
+  const docsDir = path.resolve(siteDir, '..', siteConfig.customDocsPath);
   const docsMetadata = await loadDocs({siteDir, docsDir, env, siteConfig});
   await generate(
     'docsMetadata.js',
     `export default ${JSON.stringify(docsMetadata, null, 2)};`
   );
 
-  /* Create source to permalink mapping */
+  /* Create source to metadata mapping */
   const sourceToMetadata = {};
   Object.values(docsMetadata).forEach(
     ({source, version, permalink, language}) => {
@@ -52,7 +52,7 @@ module.exports = async function load(siteDir) {
   // resolve the theme
   const themePath = loadTheme(siteDir);
 
-  const baseUrl = siteConfig.baseUrl || '/';
+  const {baseUrl} = siteConfig;
   const versionedDir = path.join(siteDir, 'versioned_docs');
   const translatedDir = path.join(siteDir, 'translated_docs');