diff --git a/package.json b/package.json
index bc7868d..eac3701 100644
--- a/package.json
+++ b/package.json
@@ -10,7 +10,6 @@
   },
   "dependencies": {
     "babel-plugin-transform-es2015-modules-commonjs": "6.10.3",
-    "babel-polyfill": "6.9.1",
     "babel-register": "6.9.0",
     "bluebird": "3.4.1",
     "book": "1.3.1",
diff --git a/yarn.lock b/yarn.lock
index eea2e61..f996796 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -129,14 +129,6 @@ babel-plugin-transform-strict-mode@^6.8.0:
     babel-runtime "^6.22.0"
     babel-types "^6.24.1"
 
-babel-polyfill@6.9.1:
-  version "6.9.1"
-  resolved "https://registry.yarnpkg.com/babel-polyfill/-/babel-polyfill-6.9.1.tgz#6b6f2f63700c4979bbe2eeb8bdebbac6ddff75bc"
-  dependencies:
-    babel-runtime "^6.9.1"
-    core-js "^2.4.0"
-    regenerator-runtime "^0.9.5"
-
 babel-register@6.9.0:
   version "6.9.0"
   resolved "https://registry.yarnpkg.com/babel-register/-/babel-register-6.9.0.tgz#dd5f3572ef5bd4082ca05471e942e4a91b162ff0"
@@ -162,7 +154,7 @@ babel-register@^6.26.0:
     mkdirp "^0.5.1"
     source-map-support "^0.4.15"
 
-babel-runtime@^6.0.0, babel-runtime@^6.22.0, babel-runtime@^6.26.0, babel-runtime@^6.9.0, babel-runtime@^6.9.1:
+babel-runtime@^6.0.0, babel-runtime@^6.22.0, babel-runtime@^6.26.0, babel-runtime@^6.9.0:
   version "6.26.0"
   resolved "https://registry.yarnpkg.com/babel-runtime/-/babel-runtime-6.26.0.tgz#965c7058668e82b55d7bfe04ff2337bc8b5647fe"
   dependencies:
@@ -1338,10 +1330,6 @@ regenerator-runtime@^0.11.0:
   version "0.11.1"
   resolved "https://registry.yarnpkg.com/regenerator-runtime/-/regenerator-runtime-0.11.1.tgz#be05ad7f9bf7d22e056f9726cee5017fbf19e2e9"
 
-regenerator-runtime@^0.9.5:
-  version "0.9.6"
-  resolved "https://registry.yarnpkg.com/regenerator-runtime/-/regenerator-runtime-0.9.6.tgz#d33eb95d0d2001a4be39659707c51b0cb71ce029"
-
 repeating@^2.0.0:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/repeating/-/repeating-2.0.1.tgz#5214c53a926d3552707527fbab415dbc08d06dda"