Express/SOS 2025

Combined 32nd International Workshop on Expressiveness in Concurrency and 22nd Workshop on Structural Operational Semantics

Monday August 25, 2025

Aarhus, Denmark

Affiliated with CONFEST 2025

Important Dates

• June 03, 2025 June 13, 2025 Paper Submission (extended)
• July 10, 2025 Notification to authors
• September 25, 2025 Final version due (Post-proceedings)

Proceedings

The workshop proceedings will be published in Electronic Proceedings in Theoretical Computer Science.

Submissions

We solicit two types of submissions:

• Full papers: between 15 and 18 pages excluding references in EPTCS style (presented at the workshop and included in the proceedings). Only material that has not been submitted/published anywhere else is allowed.
• Short papers of up to 5 pages excluding references in EPTCS style (presented at the workshop, but not included in the proceedings). We allow submissions of already published material.

Submission is performed through the EXPRESS/SOS 2025 EasyChair server.

We are planning a special issue with selected papers from EXPRESS/SOS 2023 and EXPRESS/SOS 2024. More information will follow closer to the event.

Invited Speakers

• Maaike Zwart
• Pedro D’Argenio

Programme Committee

• Giorgio Bacci (University of Aalborg, Denmark) co-chair

• Cinzia Di Giusto (Université Côte d’Azur, France) co-chair

• Valentina Castiglioni (Eindhoven University of Technology)
• Paola Giannini (Universita’ del Piemonte Orientale)
• Elli Anastasiadi (Aalborg University)
• Ping Hou (University of Oxford)
• Luc Edixhoven (University of Southern Denmark)
• Claudio Antares Mezzina (Università di Urbino)
• Benjamin Bisping (TU Berlin)
• Bas van den Heuvel (Karlsruhe University of Applied Sciences)
• Kirstin Peters (Universität Augsburg)
• Hans Hüttel (Aalborg University)
• Daniele Gorla (University of Rome “La Sapienza”)
• Georgiana Caltais (University of Twente)
• Alceste Scalas (Technical University of Denmark)
• Rob van Glabbeek (University of Edinburgh)
• Elena Zucca (University of Genova)
• Antonis Achilleos (Reykjavik University)
• Anna Philippou (University of Cyprus)
• Andreia Mordido (University of Lisbon)

Organisers

For questions, please contact:

• Giorgio Bacci, University of Aalborg, Denmark
• Cinzia Di Giusto, Université Côte d’Azur, France

Registration

Express/SOS 2025 is planned as a physical event, with certain support for remote presence, for speakers and other participants who are unable or unwilling to come. To register for Express/SOS 2025, please visit the registration page of CONFEST 2025.

Express/Sos can be followed via Zoom

Program

Invited talks

Maaike Zwart: Sketches of a distributive law

Abstract: Distributive laws provide a way to compose (co)monads. But finding a distributive law for two given monads can be difficult, or even impossible. Shifting perspective can help find and (dis)prove candidate distributive laws. In this talk I will show three equivalent notions of distributive laws (for monad-monad compositions), sliding from categorical to algebraic. I will discuss the advantages and disadvantages of each viewpoint, and showcase research where each has been particularly useful. I will finish by showing how I use all three perspectives in a current research project of mine. No prior knowledge of category theory, monads, or distributive laws is needed.

Pedro D’Argenio: A modest talk on Modest

Abstract: Modest is a high-level language inspired by classical process algebras, thus compositional modeling is an integral feature. It has been designed to capture a large class of behaviors including those that combine continuous stochastic behavior with discrete control decisions. In this talk I would discuss the language Modest and the toolset that supports it focusing on the modes engine and the techniques of Lightweight Scheduling Sampling and Q-learning to analyze models in which probabilistic and non-deterministic choices interact. In particular we will use two case studies as motivation: one focusing on delay tolerant networks for satellite and space systems and the other on the truck dispatching problem in open-pit mines.