demos/cluster and demos/transaction-propagation have its client to test those, and is executed by mvn exec:java. But now it's unexpectedly skipped with:

[INFO] skipping execute as per configuraion

It didn't happen when I tested same thing a few weeks ago. Maybe exec-maven-plugin version is changed somehow? I tried maven 3.0.5, 3.1.1 and 3.2.3, and all of those have same issue. Anyway, it can be avoided once we specify skip=false for exec-maven-plugin configuration in a client pom.xml.