Konrad with silly hat work:
I am a proud member1 of the Akka team at Lightbend (previously known as Typesafe) since 2014. Focused on high-performance distributed systems and concurrency.


I have created and maintain these very popular OSS projects:

  • maven git-commit-id plugin – used by various "top" companies and open source projects (spring boot, neo4j etc.)
  • sbt-jmh – an SBT plugin making it possible to benchmark Scala code using OpenJDK JMH (which is a real pain to do without this).

Most notable open source collaborations / contributions:

  • Reactive Streams – (top contributor commit stats wise, and collaborated on wording and semantics with a team of unbelievably smart people). I also implemented its Technology Compatibility Kit, thanks to which all implementations actually really do handle the various edge cases of the tricky RS protocol.
  • Part of the Scala Platform Committee, working towards evolving the Scala library ecosystem; representing the performance, HTTP and distributed computing aspects of the community.

Communities I'm actively involved with:

  • Polish Java User Group
  • GeeCON – the all-around-the-JVM conference gathering more than 1,000 passionate people attending annually in Kraków, Poland since 2009 (and now internationally as well, with editions in Prague)
  • Kraków Scala User Group (1 of 2 original founders)
  • SCKRK (co-organizer, core team, since early days)
  • Lambda Lounge Kraków (now mostly inactive)
  • PaperCup London – the London equivalent of SCKRK, which operated while I was living in London and doing a computer science reading club

I founded, and have handed over leadership to the next generation of community leaders:

  • GDGKraków – which when it was founded was back then known as "Kraków Google Technology User Group" (if you remember those) and have lead it for years, until handing over leadership to Mateusz Herych, a great friend I made through GDG and his KrakDroid initiatives.


  • Awarded title of Java Champion in 2017, partially for contributions in Poland's and international IT scene as well as the Reactive Streams efforts,
  • Best (masters) thesis award 2015, awarded by e-point a private company holding such competition. blog.

Selected talks:

  • Networks and Types – the Future of Akka
  • The best is yet to come, kickstarting into 2018 @ ScalaDays CPH 2017
  • Zen of Akka
    • youtube delivered in Tokyo's Scala Matsuri conference,
    • and Scala Days 2017 New York (youtube), where it was voted "best talk".
  • The Need for Async
    • youtube Scala World version has more hands on, LambaDays is more conceptual but fun
  • "distributed consensus aka. what do we do for lunch?"
  • ...
  • "git. yeah, it's that simple"
    • first talk I ever did publicly, kind of fun that already back then heavy use of images to convey meanings was my style.


  • My nickname "ktoso" is pronounced as ktɔː-sɔː.
    • It originates from a typo. In Polish "kto? co?" means "who? what?", which is the questions used to explain the nominative case in the Polish language.
  • I've been jokingly referred to as "one of the first Scala users in Poland". There is some truth in that, though I likely wasn't the first, yet may have been one of the first actively promoting it publicly.
  • The portrait used on the top of this created thanks to Jon Pretty, as thanks for hopping on and doing a last minute talk during Scala.World.

  • I live by the motto "Life is Study!", which originates from the 1995 OVA series Golden Boy (below, scene from 1st episode):