diff --git a/package.json b/package.json
index 0946c66..ab64f77 100644
--- a/package.json
+++ b/package.json
@@ -15,6 +15,16 @@
     "scripts" : {
         "test" : "tap test/*.js"
     },
+    "testling" : {
+        "files" : "test/*.js",
+        "browsers" : {
+            "ie" : [ 6, 7, 8, 9 ],
+            "ff" : [ 3.5, 10, 15.0 ],
+            "chrome" : [ 10, 22 ],
+            "safari" : [ 5.1 ],
+            "opera" : [ 12 ]
+        }
+    },
     "repository" : {
         "type" : "git",
         "url" : "git://github.com/substack/defined.git"
diff --git a/readme.markdown b/readme.markdown
index 2280351..9616195 100644
--- a/readme.markdown
+++ b/readme.markdown
@@ -2,6 +2,8 @@
 
 return the first argument that is `!== undefined`
 
+[![browser support](http://ci.testling.com/substack/defined.png)](http://ci.testling.com/substack/defined)
+
 [![build status](https://secure.travis-ci.org/substack/defined.png)](http://travis-ci.org/substack/defined)
 
 Most of the time when I chain together `||`s, I actually just want the first