diff --git a/.babelrc b/.babelrc
index a5efeb7..2766cee 100644
--- a/.babelrc
+++ b/.babelrc
@@ -7,7 +7,7 @@
             {
                 "modules": false,
                 "targets": {
-                    "ie": 9
+                    "ie": 11
                 }
             }
         ]
diff --git a/.eslintrc.js b/.eslintrc.js
index 7de629b..ccb32bf 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -2,7 +2,7 @@
 
 module.exports = {
 
-    "extends": "futagozaryuu/node-v4",
+    "extends": "futagozaryuu/node-v6",
     "root": true,
     "rules": {
 
diff --git a/.travis.yml b/.travis.yml
index 423fdaf..99eb069 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,9 +3,9 @@ sudo: false
 language: node_js
 
 node_js:
-  - "4"
   - "6"
   - "8"
+  - "10"
 
 after_success:
   - yarn coverage
diff --git a/docs/notes/compatibility.md b/docs/notes/compatibility.md
index 1987c84..440cdb1 100644
--- a/docs/notes/compatibility.md
+++ b/docs/notes/compatibility.md
@@ -2,9 +2,9 @@
 
 Both the parser generator and generated parsers should run well in the following environments:
 
-* Node.js 4+
-* Internet Explorer 9+
-* Edge
+* Node.js v6+
+* Internet Explorer 11
+* Microsoft Edge
 * Firefox
 * Chrome
 * Safari
diff --git a/package.json b/package.json
index ba6c160..ae6bea2 100644
--- a/package.json
+++ b/package.json
@@ -65,6 +65,6 @@
         "vinyl-source-stream": "2.0.0"
     },
     "engines": {
-        "node": ">=4"
+        "node": ">= 6"
     }
 }