Notes on GandALF 2026

For several reasons, I have attended very few conferences and workshops for quite a while. However, I made an exception for GandALF 2026, which was held in Aalborg in the period 15-17 September 2026. I am glad that I did so.  

GandALF is a small symposium devoted to games, automata, logics and formal verification. This year's edition of the event was the seventeenth since the symposium's inception and had 25 participants, 12 contributed presentations selected by the PC and three invited talks. I thoroughly enjoyed both the scientific and the social programmes, meeting some good friends and some young researchers in a relaxed and friendly environment, listening to the excellent talks and discussing a variety of topics with the other attendees. To be honest, these days, I prefer taking part in small scientific gatherings than in very big ones. 

The three invited talks featured at GandALF 2026 were delivered, in order of appearance, by Ezio Bartocci, Sarah Winter and Nicola Cotumaccio, three colleagues at different stages of their research careers whose research spans different topics covered by GandALF. Ezio told us about some of his recent work on rule-guided explainable testing and improvement of deep-reinforcement-learning policies (see this paper, for instance). Sarah's talk covered some of her work with Martin Zimmermann on game-based approaches to model checking some logics for hyperproperties (for example, see their CONCUR 2025 article). Nicola's talk described the connections between automata theory and data compression, focusing on Wheeler automata (see a short summary of his award-winning PhD thesis and his recent papers on DBLP; search for "Wheeler"). The talks were all carefully planned and well delivered, giving a clear message to the audience. The speakers made me want to learn more about the research topics they presented, which IMHO is always one of the signs of a good talk. 

The contributed presentations were also of high quality and, especially on the first day, made explicit references to GandALF and the Lord of the Rings 😀

On behalf of the steering committee for GandALF, I thank the GandALF 2026 PC, co-chaired by Giorgio Bacci and Mickael Randour, for putting together an interesting scientifc programme and the organising committee (Elli Anastasiadi, Giorgio Bacci and Giovanni Bacci) for the lovely social programme. It was a pleasure to have the opportunity to visit one of my stamping grounds and one of my previous departments. I wish GandALF good luck for the future. Next year's edition of the symposium will be held at the University of Mons.