diff --git a/README.md b/README.md
index f7cfb4fd0..5517e642d 100644
--- a/README.md
+++ b/README.md
@@ -16,7 +16,7 @@ cd packages/@vue/cli
 yarn link
 
 # create test projects in /packages/test
-export VUE_CLI_DEBUG=true
+export VUE_CLI_DEBUG=true # necessary for local tests to work
 cd -
 cd packages/test
 vue create test-app
diff --git a/packages/@vue/cli/lib/Creator.js b/packages/@vue/cli/lib/Creator.js
index bb157279c..ec0f31281 100644
--- a/packages/@vue/cli/lib/Creator.js
+++ b/packages/@vue/cli/lib/Creator.js
@@ -10,6 +10,7 @@ const installDeps = require('./util/installDeps')
 const PromptModuleAPI = require('./PromptModuleAPI')
 const writeFileTree = require('./util/writeFileTree')
 const { logWithSpinner, stopSpinner } = require('./util/spinner')
+const updatePackageForDev = require('./util/updatePackageForDev')
 
 const {
   error,
@@ -230,20 +231,3 @@ module.exports = class Creator {
     }
   }
 }
-
-function updatePackageForDev (targetDir, deps) {
-  const pkg = require(path.resolve(targetDir, 'package.json'))
-  pkg.devDependencies = {}
-  deps.forEach(dep => {
-    pkg.devDependencies[dep] = require(path.resolve(
-      __dirname,
-      '../../../',
-      dep,
-      'package.json'
-    )).version
-  })
-  fs.writeFileSync(
-    path.resolve(targetDir, 'package.json'),
-    JSON.stringify(pkg, null, 2)
-  )
-}
diff --git a/packages/@vue/cli/lib/util/updatePackageForDev.js b/packages/@vue/cli/lib/util/updatePackageForDev.js
new file mode 100644
index 000000000..9f53663c3
--- /dev/null
+++ b/packages/@vue/cli/lib/util/updatePackageForDev.js
@@ -0,0 +1,21 @@
+// dev only
+
+const fs = require('fs')
+const path = require('path')
+
+module.exports = function updatePackageForDev (targetDir, deps) {
+  const pkg = require(path.resolve(targetDir, 'package.json'))
+  pkg.devDependencies = {}
+  deps.forEach(dep => {
+    pkg.devDependencies[dep] = require(path.resolve(
+      __dirname,
+      '../../../',
+      dep,
+      'package.json'
+    )).version
+  })
+  fs.writeFileSync(
+    path.resolve(targetDir, 'package.json'),
+    JSON.stringify(pkg, null, 2)
+  )
+}