Portrait M.Sc. Benoit Daloze

Johannes Kepler Universität
Institut für Systemsoftware
Altenberger Straße 69
4040 Linz, Austria


Research Interests

  • Concurrency in dynamically-typed programming languages
  • Optimizations for dynamically-typed languages
  • Virtual Machines


  • TruffleRuby, a high performance implementation of the Ruby programming language on top of Truffle and Graal.
  • Mozart-Graal, an implementation of the Oz programming language on top of Truffle and Graal.


  • Daloze, B.; Tal, A.; Marr, S.; Mössenböck, H.; Petrank, E.:
    Parallelization of Dynamic Languages: Synchronizing Built-in Collections
    Conf. on Object-Oriented Programming Systems, Languages, and Applications (SPLASH/OOPSLA'18), Nov 4-9, Boston, MA, USA
    A method for making built-in collections thread-safe by default with no single-threaded overhead and allowing scalability.

  • Marr, S.; Daloze, B.:
    Few Versatile vs. Many Specialized Collections - How to design a collection library for exploratory programming?
    Proceedings of the 4th Edition of the Programming Experience Workshop (PX/18), Nice, France, April 9-12, 2018. (accepted for publication).
    A study of the design of collection libraries in 14 languages and how it influences programmer productivity.

  • Daloze, B.; Marr, S.; Bonetta, D.; Mössenböck, H.:
    Efficient and Thread-Safe Objects for Dynamically-Typed Languages
    Annual ACM SIGPLAN Conference on Object-Oriented Programming, Systems, Languages, and Applications 2016 (OOPSLA'16), Amsterdam, Netherlands, Nov.2 - Nov.4, 2016.
    A thread-safe object model for objects to which fields can be added or removed dynamically (such as in JS, Ruby, Python, etc).

  • Marr, S.; Daloze, B.; Mössenböck, H.:
    Cross-Language Compiler Benchmarking - Are We Fast Yet?
    Dynamic Languages Symposium (DLS'16), Amsterdam, Netherlands, Nov.1, 2016.
    A benchmark suite composed of 14 benchmarks, in 6 managed programming languages to compare compiler effectiveness.

  • Daloze, B.; Seaton, C.; Bonetta, D.; Mössenböck, H.:
    Techniques and Applications for Guest-Language Safepoints
    Int. Workshop on Implementation, Compilation, Optimization of Object-Oriented Languages, Programs and Systems (ICOOOLPS'15), July 6, 2015, Prague, Czech Republic
    A mechanism enabling powerful features like interrupting all threads to execute arbitrary code at zero cost on normal execution.

  • Daloze, B.:
    Extending Mozart 2 to Support Multicore Processors
    Master thesis, Universitö Catholique de Louvain, Belgium, 2014.
    Extension of the new implementation of Oz, Mozart 2, to allow multiple virtual machines to run in parallel in a single operating system process.


Other Activities

  • Committer of CRuby (aka MRI): the reference implementation of Ruby.
  • Maintainer of ruby/spec: the standard executable specification of the Ruby programming language.