I’m Jacek Laskowski, an independent consultant who offers development and training services for Apache Spark (and Scala, sbt, Akka, with a flavour of Apache Kafka, Apache Mesos, RxScala). I run Warsaw Scala Enthusiasts and Warsaw Spark meetups.
Contact me at firstname.lastname@example.org to discuss Spark opportunities, e.g. courses, workshops, or other mentoring or development services.
I'm currently working on the notes Mastering Apache Spark. You should definitely check it out!