TLA+ Community Event at ETAPS 2025

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This Sunday, I'll be attending (and speaking at) the TLA+ Community Event, co-located with ETAPS 2025 in Hamilton, Ontario. 

The setting is fitting. ETAPS (European Joint Conferences on Theory and Practice of Software) has long been a hub for research that combines theory with software engineering. It seems that, while the U.S. academia largely left software engineering to industry, European researchers remained more strongly involved in software engineering discipline. ETAPS has consistently hosted work on model checking, type systems, static analysis, and formal methods. Think of work on abstract interpretation, K frameworks, or compilers verified in Coq.

I have never been to ETAPS before. It seems that they are rebranding as "International Joint Conferences On Theory and Practice of Software" and droppping the European. And this year is the first time, after 28 years, that the event moves outside of Europe. Interesting.

McMaster University, the ETAPS 2025 host, is a strong research school, particularly in health sciences and engineering. Huh, the department is called "Department of Computing & Software", and it gives a degree in Computer Science and several others in Software Engineering. It's also just an hour's drive from Buffalo, where I live, so this is a rare hometown event for me.


The TLA+ Community Event runs all day Sunday, May 4. The program features researchers and practitioners from academia and industry. Some highlights:

  • ModelFuzz for distributed systems (MPI-SWS)  
  • Source-level safety checking via C-to-PlusCal translation (Asterios Technologies)  
  • TLA+ in Python notebooks (Loyola University Chicago)  
  • Modeling and Modular Verification of MongoDB’s distributed transactions  (joint work between Will Schultz and yours truly)
  • How do we use TLA+ for statistical properties? (by Jesse Jiryu Davis)
  • And a talk on building TLA+ tooling (by Andrew Helwer)

There's no formal proceedings from the event, but slides and recordings will be online.

I would be amiss if I don't mention the TLA+ Foundation Grant Program. The TLA+ Foundation is accepting proposals for grant funding to support projects that advance the state of the art in TLA+ and improve the experience of using TLA+ in research and industry. Grants will be awarded based on the significance of the proposed work and its potential to benefit the TLA+ community.


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