Programming Languages

Dagstuhl Seminar on Domain-Specific Languages

Jonathan Brachthäuser
Jonathan Immanuel Brachthäuser
attends the Dagstuhl-Seminar on “Algebraic Effect Handlers go Mainstream” from April 22 to 27, 2018.

Group photo of the participants of the Dagstuhl Seminar.
Photo courtesy of Schloss Dagstuhl - LZI GmbH (2018).


Algebraic effect handlers are a program structuring paradigm with rising popularity in the functional programming language community. Effect handlers are less wide-spread in the context of imperative, object oriented languages. We present library implementations of algebraic effects in Scala and Java. Both libraries are centered around the concept of handler/capability passing and a shallow embedding of effect handlers. While the Scala library is based on a monad for multi-prompt delimited continuations, the Java library performs a CPS translation as bytecode instrumentation. We discuss design decisions and implications on extensibility and performance.

Further Information


Effekt: Extensible Algebraic Effects in Scala (Short Paper)

by Jonathan Immanuel Brachthäuser and Philipp Schuster

In Proceedings of the International Symposium on Scala. ACM Press, 2017.

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Effect Handlers for the Masses

by Jonathan Brachthäuser, Philipp Schuster, and Klaus Ostermann

In Proc. Int’l Conf. Object-Oriented Programming, Systems, Languages and Applications (OOPSLA). ACM Press, 2018.

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