diff --git a/package.json b/package.json
index 1f57829..29149eb 100644
--- a/package.json
+++ b/package.json
@@ -24,7 +24,7 @@
   "homepage": "https://github.com/steveblue/angular2-rollup#readme",
   "dependencies": {
     "@angular-devkit/build-optimizer": "^0.6.8",
-    "async": "^2.6.0",
+    "async": "^3.2.2",
     "chokidar": "^2.0.2",
     "colors": "^1.1.2",
     "commander": "^2.14.1",
diff --git a/yarn.lock b/yarn.lock
index 03044f9..44f28f5 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -106,11 +106,9 @@ async-foreach@^0.1.3:
   version "0.1.3"
   resolved "https://registry.yarnpkg.com/async-foreach/-/async-foreach-0.1.3.tgz#36121f845c0578172de419a97dbeb1d16ec34542"
 
-async@^2.6.0:
-  version "2.6.1"
-  resolved "https://registry.yarnpkg.com/async/-/async-2.6.1.tgz#b245a23ca71930044ec53fa46aa00a3e87c6a610"
-  dependencies:
-    lodash "^4.17.10"
+async@^3.2.2:
+  version "3.2.2"
+  resolved "https://registry.yarnpkg.com/async/-/async-3.2.2.tgz#2eb7671034bb2194d45d30e31e24ec7e7f9670cd"
 
 asynckit@^0.4.0:
   version "0.4.0"
@@ -1104,7 +1102,7 @@ lodash.debounce@^4.0.8:
   version "4.0.8"
   resolved "https://registry.yarnpkg.com/lodash.debounce/-/lodash.debounce-4.0.8.tgz#82d79bff30a67c4005ffd5e2515300ad9ca4d7af"
 
-lodash@^4.0.0, lodash@^4.17.10, lodash@^4.17.15, lodash@~4.17.10:
+lodash@^4.0.0, lodash@^4.17.15, lodash@~4.17.10:
   version "4.17.20"
   resolved "https://registry.yarnpkg.com/lodash/-/lodash-4.17.20.tgz#b44a9b6297bcb698f1c51a3545a2b3b368d59c52"