diff --git a/.travis.yml b/.travis.yml
index 2316d09e..d1c7a412 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,4 +7,9 @@ before_install:
 env:
   - TEST_OS=7.1
   - TEST_OS=8.1
-script: xctool -workspace AsyncDisplayKit.xcworkspace -scheme AsyncDisplayKit -sdk iphonesimulator8.1 -destination "platform=iOS Simulator,OS=${TEST_OS},name=iPhone 5" build test
+script: ./build.sh $TEST_OS
+
+# whitelist
+branches:
+  only:
+    - master
diff --git a/build.sh b/build.sh
new file mode 100755
index 00000000..5ad98e74
--- /dev/null
+++ b/build.sh
@@ -0,0 +1,7 @@
+#!/bin/sh
+xctool \
+    -workspace AsyncDisplayKit.xcworkspace \
+    -scheme AsyncDisplayKit \
+    -sdk iphonesimulator8.1 \
+    -destination "platform=iOS Simulator,OS=${1},name=iPhone 5" \
+    build test