diff --git a/.travis.yml b/.travis.yml
index 9228101..a58180a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,9 +1,9 @@
 language: node_js
 
 node_js:
+  - 10
   - 8
   - 6
-  - 4
 
 os:
   - linux
diff --git a/appveyor.yml b/appveyor.yml
index e36606d..0d4128f 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -1,9 +1,9 @@
 version: '{build}'
 environment:
   matrix:
-    - nodejs_version: '4'
-    - nodejs_version: '6'
+    - nodejs_version: '10'
     - nodejs_version: '8'
+    - nodejs_version: '6'
 branches:
   only:
     - master
diff --git a/package.json b/package.json
index 3489e11..0b9fdd7 100644
--- a/package.json
+++ b/package.json
@@ -57,7 +57,7 @@
     "xo": "^0.20.0"
   },
   "engines": {
-    "node": ">=4"
+    "node": ">=6"
   },
   "files": [
     "lib"