diff --git a/.travis.yml b/.travis.yml
index d62ea0e5..326f3a74 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -75,10 +75,7 @@ jobs:
     - stage: Unit Tests
       env: CANVAS=canvas-prebuilt
       node_js: "8"
-      cache:
-        directories:
-          - ''
-      install: npm install && npm remove canvas && npm install canvas-prebuilt@^1.6.11
+      install: npm install && npm remove canvas && npm install canvas-prebuilt@^1.6.11 qunit@2.6.1
       addons:
         apt:
           packages: # avoid installing packages
diff --git a/package.json b/package.json
index 4a3c24e5..6912f432 100644
--- a/package.json
+++ b/package.json
@@ -60,7 +60,7 @@
     "testem:ci": "testem ci"
   },
   "optionalDependencies": {
-    "canvas": "^1.6.12",
+    "canvas": "^1.6.13",
     "jsdom": "^9.12.0",
     "xmldom": "0.1.x"
   },