Clojurians Log v2

I am just starting out with Spark and am lost as to why my task is failing. I have downloaded the latest version of spark (2.1.1) and have included [org.apache.spark/spark-core_2.11 "2.1.1"] and [org.apache.spark/spark-streaming_2.11 "2.1.1"] in my project. I also started the master via ./sbin/start-master.sh and a slave ./sbin/start-slave.sh <spark://kenny-ubuntu:7077>. Once I load my ns that require's powderkeg in the REPL, I get a bunch of output that all looks unalarming. However, if I try to run one of the examples in the powderkeg README, I get the below exception: The example:

(into [] ; no collect, plain Clojure
      (keg/rdd ["This is a firest line"  ; here we provide data from a clojure collection.
                "Testing spark"
                "and powderkeg"
                "Happy hacking!"]
               (filter #(.contains % "spark"))))

Exception: https://pastebin.com/Ght3ZAci I have spent several hours googling this error and have not found any solution that fixes the issue. Any ideas on how to proceed?