diff --git a/Makefile b/Makefile
index 8893a65..8aac539 100644
--- a/Makefile
+++ b/Makefile
@@ -11,7 +11,7 @@ VM_IMAGE=$(CURDIR)/test/images/$(TEST_OS)
 # stamp file to check if/when npm install ran
 NODE_MODULES_TEST=package-lock.json
 # one example file in dist/ from webpack to check if that already ran
-WEBPACK_TEST=dist/index.css
+WEBPACK_TEST=dist/manifest.json
 
 all: $(WEBPACK_TEST)
 
diff --git a/webpack.config.js b/webpack.config.js
index 28540ee..e524c9a 100644
--- a/webpack.config.js
+++ b/webpack.config.js
@@ -23,7 +23,7 @@ const plugins = [
 /* Only minimize when in production mode */
 if (production) {
     plugins.unshift(new CompressionPlugin({
-        test: /\.(js|html)$/,
+        test: /\.(js|html|css)$/,
         deleteOriginalAssets: true
     }));
 }