diff --git a/.travis.yml b/.travis.yml
index 087c11e..98dcf4a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,6 +6,7 @@ cache:
 notifications:
   email: false
 node_js:
+  - 4
   - 6
 before_script:
   - npm prune
diff --git a/package.json b/package.json
index 79ac7d2..a38954c 100644
--- a/package.json
+++ b/package.json
@@ -42,7 +42,7 @@
     }
   },
   "engines": {
-    "npm": ">=3",
-    "node": ">=6"
+    "npm": ">=2",
+    "node": ">=4"
   }
 }