diff --git a/CHANGES.txt b/CHANGES.txt
index 547fc07b20..e3bda6cdbf 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,4 +1,5 @@
 3.0.11
+ * Dump threads when unit tests time out (CASSANDRA-13117)
  * Better error when modifying function permissions without explicit keyspace (CASSANDRA-12925)
  * Indexer is not correctly invoked when building indexes over sstables (CASSANDRA-13075)
  * Read repair is not blocking repair to finish in foreground repair (CASSANDRA-13115)
diff --git a/build.xml b/build.xml
index 2d33de603f..476cd14b20 100644
--- a/build.xml
+++ b/build.xml
@@ -1108,6 +1108,8 @@
       </rat:report>
     </target>
 
+    <!-- use https://github.com/krummas/jstackjunit to get thread dumps when unit tests time out -->
+  <taskdef name="junit" classname="org.krummas.junit.JStackJUnitTask" classpath="lib/jstackjunit-0.0.1.jar"/>
   <target name="build-test" depends="build" description="Compile test classes">
     <javac
      debug="true"
diff --git a/lib/jstackjunit-0.0.1.jar b/lib/jstackjunit-0.0.1.jar
new file mode 100644
index 0000000000..ba399763c0
Binary files /dev/null and b/lib/jstackjunit-0.0.1.jar differ
diff --git a/lib/licenses/jstackjunit-0.0.1.txt b/lib/licenses/jstackjunit-0.0.1.txt
new file mode 100644
index 0000000000..d5c4984908
--- /dev/null
+++ b/lib/licenses/jstackjunit-0.0.1.txt
@@ -0,0 +1,209 @@
+
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