I am an IT freelancer specializing in apache-spark, delta-lake, apache-kafka and kafka-streams (with scala and sbt). I offer consultancy, courses, workshops, mentoring and software development services.

Contact me at jacek@japila.pl or DM me on twitter @jaceklaskowski.

I'm best known by "The Internals Of" online books available free of charge at https://books.japila.pl/.

I run Warsaw Data Engineering meetups.