diff --git a/.travis.yml b/.travis.yml
index c2ebc78..2d38569 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,5 +2,8 @@ language: node_js
 node_js:
   - "0.10"
   - "0.12"
-before_install: "npm install -g npm && npm cache clean"
+  - "4"
+  - "6"
+  - "7"
+  - "8"
 script: "npm run-script travis"
diff --git a/bootstrap-unexpected-markdown.js b/bootstrap-unexpected-markdown.js
index fcb894d..441008f 100644
--- a/bootstrap-unexpected-markdown.js
+++ b/bootstrap-unexpected-markdown.js
@@ -4,5 +4,7 @@ unexpected = require('unexpected');
 unexpected.output.preferredWidth = 80;
 unexpected.installPlugin(require('./lib/unexpected-sinon'));
 require('./test/monkeyPatchSinonStackFrames');
-Promise = require('rsvp');
+if (typeof Promise === 'undefined') {
+    Promise = require('rsvp').Promise;
+}
 sinon = require('sinon');
diff --git a/package.json b/package.json
index 3896fe2..f168a18 100644
--- a/package.json
+++ b/package.json
@@ -44,7 +44,7 @@
     "serve": "*",
     "sinon": "1.17.7",
     "unexpected": "10.23.0",
-    "unexpected-documentation-site-generator": "^4.2.3",
-    "unexpected-markdown": "1.4.1"
+    "unexpected-documentation-site-generator": "4.5.0",
+    "unexpected-markdown": "1.7.2"
   }
 }