Curry On
June 19-20th, 2017

With Age comes Beauty - Past, Present, and Future of Efficient Immutable Collections
Michael Steindorfer
Delft University of Technology



In 2016’s Curry-On keynote, David Nolen elected Clojure’s efficient immutable collections to his shortlist of four transformative technologies originating from research, which made the language a success story in the long run. "Oldies, but goodies", Nolen said. The foundations of nowadays efficient immutable collections, which are based on hash-tries, were pioneered in the late 50s and early 60s. However, rejuvenated research interest in this topic just met the enthusiasm of functional programmers roughly a decade ago, after Clojure and Scala broadly started embracing well-performing functional data structures. This talk will quickly go back to the origins of prefix trees, to then introduce the basic ingredients it takes to build efficient immutable collections that are based on hash-tries. The main part of this talk will pickup where Clojure and Scala left off: focusing on current research involving hash-tries, and projecting where the journey might go. Engineers, researchers, and programming language enthusiasts, let’s have a talk!


Michael is a researcher at the Delft University of Technology in the Netherlands. In his work he tries to increase the efficiency of functional data structures and to optimize programming language runtimes by applying the right data structures. Apart from all that, he likes photography and is optimistic by nature.

Michael previously worked at CWI, the Dutch National Research Center for Mathematics and Computer Science, and holds a PhD in computer science from the University of Amsterdam.