diff --git a/lib/bundle/concat_source_es.js b/lib/bundle/concat_source_es.js
index 558984de..f29973c7 100644
--- a/lib/bundle/concat_source_es.js
+++ b/lib/bundle/concat_source_es.js
@@ -7,7 +7,7 @@ const removeActiveSourceKeys = require("../node/remove_active_source_keys");
 const rollup = require("steal-rollup");
 
 const moduleNameFromSpecifier = dependencyResolver.moduleNameFromSpecifier;
-const CJS_PROXY_PREFIX = '\0commonjs-proxy:';
+const CJS_PROXY_PREFIX = '\0commonjs-proxy-';
 
 module.exports = function(bundle, options) {
 	let removeDevelopmentCode = options.removeDevelopmentCode;
diff --git a/package.json b/package.json
index 2b42818d..223ea0d3 100644
--- a/package.json
+++ b/package.json
@@ -30,7 +30,7 @@
     "pdenodeify": "^0.1.0",
     "prettier": "1.12.0",
     "pump": "^3.0.0",
-    "rollup-plugin-commonjs": "<=9.3.2",
+    "rollup-plugin-commonjs": "^9.3.4",
     "steal": "^2.2.0",
     "steal-bundler": "^0.3.6",
     "steal-parse-amd": "^1.0.0",