diff --git a/dist/server/config.js b/dist/server/config.js
index f0d0abe3378f..7f55f32c4bd7 100644
--- a/dist/server/config.js
+++ b/dist/server/config.js
@@ -50,8 +50,7 @@ exports.default = function (baseConfig, configDir) {
   return (0, _extends3.default)({}, customConfig, config, {
     // We need to use our and custom plugins.
     plugins: [].concat((0, _toConsumableArray3.default)(config.plugins), (0, _toConsumableArray3.default)(customConfig.plugins || [])),
-    module: (0, _extends3.default)({}, config.module, {
-      // We need to use our and custom loaders.
+    module: (0, _extends3.default)({}, config.module, customConfig.module || {}, {
       loaders: [].concat((0, _toConsumableArray3.default)(config.module.loaders), (0, _toConsumableArray3.default)(customConfig.module.loaders || []))
     })
   });
diff --git a/src/server/config.js b/src/server/config.js
index 2be900af9404..1393904998dd 100644
--- a/src/server/config.js
+++ b/src/server/config.js
@@ -56,6 +56,7 @@ export default function (baseConfig, configDir) {
     module: {
       ...config.module,
       // We need to use our and custom loaders.
+      ...customConfig.module || {},
       loaders: [
         ...config.module.loaders,
         ...customConfig.module.loaders || [],