diff --git a/bin/webpack b/bin/webpack
index 008ecb22f7c..14ed741a787 100755
--- a/bin/webpack
+++ b/bin/webpack
@@ -1,7 +1,7 @@
 #!/usr/bin/env ruby
 
 ENV["RAILS_ENV"] ||= ENV["RACK_ENV"] || "development"
-ENV["NODE_ENV"]  ||= "development"
+ENV["NODE_ENV"]  ||= ENV["RAILS_ENV"]
 
 require "pathname"
 ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../../Gemfile",
diff --git a/config/webpack/test.js b/config/webpack/test.js
new file mode 100644
index 00000000000..397a221905f
--- /dev/null
+++ b/config/webpack/test.js
@@ -0,0 +1,8 @@
+const { merge } = require('webpack-merge');
+
+const sharedConfig = require('./shared');
+
+module.exports = merge(sharedConfig, {
+  mode: 'development',
+  cache: false,
+});