diff --git a/lib/packExternalModules.js b/lib/packExternalModules.js
index 9a192ff130..37ba42bc1a 100644
--- a/lib/packExternalModules.js
+++ b/lib/packExternalModules.js
@@ -126,8 +126,8 @@ module.exports = {
       };
       const prodModules = getProdModules(getExternalModules(compileStats), packagePath);
       _.forEach(prodModules, prodModule => {
-        const splitModule = _.split(prodModule, '@', 2);
-        modulePackage.dependencies[splitModule[0]] = splitModule[1];
+        const splitModule = _.split(prodModule, '@');
+        modulePackage.dependencies[_.first(splitModule)] = _.join(_.tail(splitModule), '');
       });
       this.serverless.utils.writeFileSync(modulePackageJson, JSON.stringify(modulePackage, null, 2));