High performance computing
Distributed computing (authored Actor based libraries part of the Akka toolkit)
Low (or no) allocation datastructures and algorithms
HTTP spec & internals - maintainer of the Akka HTTP web server
Konrad Malawski is a core developer at Lightbend working on Akka, a distributed systems toolkit for the JVM. He is currently responsible for the Akka HTTP module, has contributed large parts of Akka Persistence and remains active in the Core modules of Akka as well. He is a leading contributor to the current Reactive Streams TCK, and maintains various other open source projects. He has founded and helps run multiple user groups including the international GeeCON conference (with it's multiple Polish, and Czech editions). When he's not coding, Konrad spreads the joy of computer science by organizing a white paper reading club, where people of all skill levels are invited to discuss and debate actual computer science topics and papers. He was named a JavaOne RockStar in 2015.