diff --git a/build/webpack.common.config.js b/build/webpack.common.config.js
index 1154a102c..3c69da6da 100644
--- a/build/webpack.common.config.js
+++ b/build/webpack.common.config.js
@@ -108,6 +108,11 @@ module.exports = {
 							}
 						],
 
+						// This is actually included in the 'es2015' preset but we need to override the
+						// `loose` option to be true
+						// TODO: stop transform-es2015-classes being loose. loose allows non-spec compliant classes.
+						[ require.resolve('babel-plugin-transform-es2015-classes'), { loose: true } ]
+
 						// converts import/export to commonjs, currently not used but
 						// will look to include it for browsers that can support modules
 						// require('babel-plugin-transform-es2015-modules-commonjs'),
diff --git a/package.json b/package.json
index bd2a33a87..c0ce94afd 100644
--- a/package.json
+++ b/package.json
@@ -70,12 +70,12 @@
     "@financial-times/n-express": "^19.0.0",
     "@financial-times/n-handlebars": "^1.15.0",
     "@financial-times/next-json-ld": "^0.1.0",
-    "ajv": "^5.2.2",
     "autoprefixer": "^6.3.6",
     "aws-sdk": "^2.7.21",
     "babel-core": "^6.25.0",
     "babel-loader": "^7.0.0",
     "babel-plugin-add-module-exports": "^0.2.1",
+    "babel-plugin-transform-es2015-classes": "^6.14.0",
     "babel-plugin-transform-es2015-modules-commonjs": "^6.8.0",
     "babel-plugin-transform-runtime": "^6.12.0",
     "babel-preset-es2015": "^6.14.0",
@@ -87,7 +87,7 @@
     "commander": "^2.9.0",
     "css-loader": "^0.28.4",
     "extract-css-block-webpack-plugin": "^1.3.0",
-    "extract-text-webpack-plugin": "^3.0.0",
+    "extract-text-webpack-plugin": "^2.1.0",
     "ft-poller": "^2.9.0",
     "handlebars-loader": "^1.4.0",
     "imports-loader": "^0.7.1",
@@ -102,7 +102,7 @@
     "sass-loader": "^6.0.5",
     "semver": "^5.3.0",
     "shellpromise": "^1.4.0",
-    "webpack": "^3.2.0",
+    "webpack": "^2.6.1",
     "webpack-merge": "^4.1.0",
     "webpack-sources": "^1.0.1",
     "webpack-stats-plugin": "^0.1.1"