SAT Live!

ModRef 2026 Call for Papers

Tue, 10 Feb 2026 00:00:00 +0100

We invite you to submit your work to ModRef 2026, the 25th workshop on Constraint Modelling and Reformulation, which will be held on 19th July 2026 in Lisbon, Portugal, as part of FLOC26.

The purpose of ModRef is to be a forum for all kinds of work in modelling for CP, MIP, SAT, SMT, and other general-purpose solvers, including:

new models or new modelling ideas for any amenable problem (whether a new application or a classic benchmark),
reformulation techniques to improve the performance of models when solved by general-purpose solvers, and
automated modelling techniques, tools, and languages.

We solicit original papers that contribute to the understanding of modelling or model reformulation.

This year ModRef will again accept paper submissions. In addition to the presentation of research results, we especially welcome submissions of novel (ongoing) work, recent breakthroughs, future directions, and descriptions of interesting aspects of existing systems.

There are three types of paper submissions:

Extended abstracts: at most two pages
Short papers: at most eight pages.
Long papers: at most fifteen pages.

References are not part of the page limit. We also accept (and encourage) non-traditional electronic submissions, such as interactive works/tool demonstrations. In this case, please contact the chairs to discuss the suitability of your submission for ModRef.

Papers should be submitted through HotCRP as PDF files following LIPIcs guidelines. There is no requirement for papers to be anonymised before submission.

All submissions will be reviewed, and those that are well-written and make a worthwhile contribution to the topic of the workshop will be allowed a time slot for a presentation at the workshop. Accepted papers will be included in non-archival electronic workshop proceedings, which will be available on ModRef’s web site. You can see some of the past accepted papers to give you an idea of the kind of contributions shared over recent years.

For more information, please see our web site https://2026.modref.org/

If you have any questions, please contact us at jordicoll@udg.edu and felix.ulrich-oltean@york.ac.uk

Jordi Coll and Felix Ulrich-Oltean Co-chairs

Call for papers: 2nd Workshop on Machine Learning for Solvers and Provers (at FLoC 2026)

Tue, 10 Feb 2026 00:00:00 +0100

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The 2nd Workshop on Machine Learning for Solvers and Provers (ML4SP)

    July 18, 2026, Lisbon, Portugal

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Workshop page: https://ml4sp.github.io/

We warmly invite you to submit your work to the 2nd Workshop on Machine Learning for Solvers and Provers (ML4SP), organised as part of the 2026 Federated Logic Conference (FLoC 2026) at Lisbon, Portugal. The workshop will run during the first block of the conference, on July 18, 2026.

Topics

Machine learning (ML) has had a substantial impact on SAT/SMT and CP solvers, as well as automated theorem provers. Recent advances have demonstrated the power of ML to inform solver heuristics, guide proof search, and optimize algorithm portfolios. Despite growing interest in this direction, work on ML for solvers and provers is often scattered across multiple research communities – SAT, SMT, CP, theorem proving, formal methods, and machine learning – with few opportunities for focused interaction.

The ML4SP workshop aims to bring together researchers and practitioners working at the intersection of machine learning and formal reasoning systems. It provides a forum for the presentation of recent work, the exchange of ideas, and the fostering of collaboration between these communities.

Topics of interest include, but are not limited to, ML-driven approaches for:

Heuristics (branching, restarts, …) in CP, SAT, SMT, and MIP solvers
Tactic selection and proof guidance in automated and interactive theorem provers
Algorithm selection, parameter tuning and algorithm configuration, and portfolio solvers
End-to-end learning for solvers and provers
Benchmark generation and instance hardness prediction
Applications of ML-enhanced reasoning in verification, synthesis, planning, and related areas
Leveraging large language models (LLMs) for solver heuristics and proof guidance

Submission

We welcome submissions describing previously published work, ongoing research, and position papers and early-stage ideas intended to stimulate discussion.

Submission should be in PDF form, following the LIPIcs guidelines. They can be:

Extended abstracts (up to two pages, excluding references); or
Full papers (up to 15 pages, excluding references).

All submissions will be reviewed by the PC members. A presentation time slot will be given to each accepted submission.

Submission link: https://submissions.floc26.org/ml4sp/

Key Dates

Submission deadline: 15 May 2026 AoE
Result notification: 25 May 2026
Camera ready: 2 July 2026
Workshop day: 18 July 2026

Organizers:

Vijay Ganesh, Georgia Tech, vganesh45@gatech.edu
Nguyen Dang, University of St Andrews, nttd@st-andrews.ac.uk

SC-Square 2026: 10th International Workshop on Satisfiability Checking and Symbolic Computation

Wed, 04 Feb 2026 00:00:00 +0100

The 11th SC-Square Workshop is a satellite event of ISSAC, held at the University of Oldenburg in Germany, from July 13 to 17, 2026.

SC-Square Workshop website

ISSAC conference website

Key Dates

Abstract submission: April 10, 2026
Submission deadline: April 17, 2026
Notification: May 22, 2026
Final version: June 1, 2026
Workshop date: July 13, 2026

Scope

Symbolic Computation is concerned with the efficient algorithmic determination of exact solutions to complicated mathematical problems. Satisfiability Checking has recently started to tackle similar problems but with different algorithmic and technological solutions.

The two communities share many central interests, but researchers from these two communities rarely interact. Also, the lack of common or compatible interfaces for tools is an obstacle to their fruitful combination. Bridges between the communities in the form of common platforms and road-maps are necessary to initiate an exchange, and to support and direct their interaction. The aim of this workshop is to provide an opportunity to discuss, share knowledge and experience across both communities.

Invited Speakers Anna Maria Bigatti (Università degli Studi di Genova, Italy) Mahsa Shirmohammadi (CNRS, Université Paris Cité, France)

Submitting to the Workshop

The workshop series has emerged from an H2020 FETOPEN CSA project “SC-Square”, which ran from 2016 to 2018. It has been continued aiming at building bridges between Satisfiability Checking and Symbolic Computation. It is open for submission and participation to everyone interested in the topics, whether or not they were members or associates of the original project.

The topics of interest include but are not limited to:

Computer Algebra and Symbolic Computation (CA)
Satisfiability Checking (SAT/SMT)
Algorithms for logical theories of arithmetics, including quantifier elimination and decision procedures
Computational Geometry
Algorithmic Group Theory
Formalized mathematics, especially in interactive theorem provers
Tools in SAT/SMT/CA, including tools that combine Symbolic Computation and Satisfiability Checking
Applications relying on Symbolic Computation or on Satisfiability Checking, including hybrid systems and controls

Submission guidelines

Submissions should be in English, formatted in Springer LNCS style and submitted via https://hotcrp.software.imdea.org/scsquare/

We invite four types of submissions:

(1) FULL PAPERS on research, case studies or tool development should present unpublished work not submitted elsewhere (with a limit of 16 pages, not counting references)

(2) EXTENDED ABSTRACTS on research, case studies or tool development should present unpublished (potentially ongoing) work not submitted elsewhere (3–5 pages, not counting references)

(3) SHORT SURVEYS that describe/explain an existing body of work in an original way (5–8 pages, not counting references)

(4) PRESENTATION-ONLY submissions on already published work, work to be published elsewhere, or work in progress on SC-Square related open problems or future challenges. Please submit an abstract for approval by the PC (with a limit of 2 pages).

To receive the appropriate level of peer review, please select the relevant category for your paper on the submission site.

For consistency, all submissions must use the LNCS style. Current lncs latex files are available from “LaTeX2e Proceedings Templates download” at: https://www.springer.com/gp/computer-science/lncs/conference-proceedings-guidelines

We plan to publish the proceedings of the workshop in digital form, hosted with CEUR-WS (see http://ceur-ws.org/). People from industry and business are warmly invited to submit papers to describe their problems, challenges, goals, and expectations for the SC-Square community.

Workshop Co-Chairs

Katherine Kosaian (University of Iowa, USA)
Alessio Mansutti (Imdea Software Institute, Spain)

Program Committee

Kyungmin Bae (Pohang University of Science and Technology, South Korea)
Rizeng Chen (Peking University, China)
Xin Chen (University of New Mexico, US)
Ruiwen Dong (University of Oxford, UK)
Matthew England (Coventry University, UK)
Stéphane Graham-Lengrand (SRI, US)
Alberto Griggio (Fondazione Bruno Kessler, Italy)
Hoon Hong (North Carolina State University, US)
Dejan Jovanovic (AWS, US)
Ariel Kellison (Code Metal, US)
George Kenison (KU Leuven, Belgium)
Hanna Lachnitt (Stanford University, US)
Pierre Mathonet (Université de Liège, Belgium)
Guillaume Melquiond (Inria and ENS Lyon, France)
Marc Moreno Maza (University of Western Ontario, Canada)
Mathias Preiner (Stanford University, US)
Philipp Rümmer (University of Regensburg, Germany)
Mohab Safey El Din (Sorbonne Université, France)
Žaneta Semanišinová (TU Dresden, Germany)
Zhikun She (Beihang University, China)

PhD positions at KU Leuven (combinatorial optimization -- Certifying algorithms / Proof logging / Explanations) (deadline March 16, 2026)

Wed, 04 Feb 2026 00:00:00 +0100

I’m looking for an excellent PhD Researchers to join my team. The candidate will help advance the state-of-the-art in combinatorial search & optimization with techniques such as proof logging or explanations.

This is a fully funded position that comes with a very competitive scholarship. The position has an expected duration of 4 years. The starting date is negotiable, but ideally this would be around the autumn of 2026.

The application deadline is March 16, 2025.

Interested? Apply here.

I’m happy to answers any remaining questions about this vacancy.

Bart Bogaerts
KU Leuven 
Phone: +32 16 32 79 26
http://www.bartbogaerts.eu

CP 2026 Call for Papers

Tue, 20 Jan 2026 00:00:00 +0100

Thirty Second Conference on Principles and Practice of Constraint Programming CP 2026 

                        July 20-23, 2026, Lisbon, Portugal

CP is the premier international event for presenting research in all aspects of computing with constraints, including, but not restricted to: theory, algorithms, environments, languages, models, systems, and applications. CP 2026 is the 32nd conference in this series and will be held in Lisbon, at ISCTE – Instituto Universitário de Lisboa (July 18-19 and July 24-25: workshops, July 20-23: main conference). This year, CP is part of the the Federated Logic Conference (FLoC) 2026.

The CP conference welcomes submissions that advance the state of the art for the underlying constraint-based technologies, as well as papers that explore the role of constraint programming within other disciplines, such as operations research, machine learning, computational sustainability, quantum computing, computational biology and (cyber)security.

Tracks and Primary Keywords

CP has lately had both a main technical track, an application track and a series of specialised tracks (e.g., machine learning, operations research, etc.) that authors could submit to and were mutually exclusive. This year, inspired by the previous CP conference, we will only have two tracks: technical and application where, as usual, the former focuses on the scientific contributions made “to” CP, while the latter focuses on scientific contributions made “with” CP. The application track is particularly interested in papers that demonstrate the effectiveness of CP in solving real-world problems, as well as those that offer generalisable insights on the challenges and benefits for both users and developers of applying CP to both academic and real-world problems.

Former specialised tracks are replaced by a set of optional primary keywords, which are in addition to the keywords requested from authors every year. Their purpose is to enable submissions to self-identify the area of focus of the CP paper, support the identification of suitable reviewers. Authors (resp. reviewers) will be able to select zero, one or more primary keywords to reflect best the thematic contributions of their CP paper (resp. reviewer expertise).

The primary keywords that can be used to qualify the particular focus of the CP research presented in the paper are:

Theory
Constraint Propagation
Filtering algorithms
Explanation & Inference
Solver
Search (Complete & Heuristic)
SAT
MaxSAT
Logic Programming
Modelling & Modelling Languages
Operations Research & Mathematical Optimisation
Machine Learning & Generative AI
Verification
Certification
Testing
Hardware
Quantum
Security & Parallelism
Model Counting
Decision Diagrams
Dynamic Programming
Symmetries
Dominance
Model/Instance Explainability

Important Dates

Submissions open: 01/02
Abstract registration: 28/02
Paper submission: 07/03
Author rebuttal: 09/04-12/04
Final notification: 30/04
Camera Ready: 07/05
Conference: 20/07-23/07

Dates are intended as 11pm Anywhere on Earth (AoE, also known as UTC-12).

Submission Instructions

The submission Web page for CP 2026 uses the HotCRP system. The change in the submission system has been made to facilitate integration within FLoC.

Papers should be submitted in the form of a PDF file following LIPIcs guidelines.

To open the conference more widely, two types of submissions are expected:

Full papers, that can use up to 15 pages (references and appendices excluded).
Short papers, that can use up to 8 pages (references and appendices excluded). Short papers cover early results or highly specific results that can be adequately reported in 8 pages. They must nonetheless respect the quality expectations of the conference. Both full and short papers should attract a wide audience and will be allocated time for presentation during the conference.

Appendices of up to 6 pages for full papers and up to 3 pages for short papers can be included and will not contribute towards the total page count provided they are clearly marked as an appendix. Supplemental material (for example, experimental results or code) may be referenced, but only if this is done without revealing the authors’ identities (for example, by using https://anonymous.4open.science) to fit our double-blind review process (see below). Papers should be self-contained and be comprehensible without reference to either appendices or supplemental material. Authors should not place elements essential to their paper in either appendices or supplemental material and indeed it will be left to the discretion of each reviewer whether they refer to this material or not.

To facilitate reviewing management, authors who intend to submit a paper to CP 2026 should submit an abstract with a maximum of 150 words, summarising the contribution of the paper and indicating the track and primary keywords by February 28, 2026. The paper submission must be completed by March 7, 2026.

All papers will go through a double-blind reviewing process, meaning that authors and reviewers are mutually anonymous. For this reason, submitted papers should not contain author names, affiliations, or links to identifying websites. References to the authors’ own papers should be cited in such a way so as to avoid revealing the authorship of the paper. Authors will also be able to submit a single rebuttal for each paper during the period.

Submissions exceeding the page limits, improperly formatted, with author names/affiliations/identifying-websites will be rejected without review. The existence of a technical report (e.g., an ArXiV report) corresponding to the submission before March 8, 2026, will not constitute grounds for rejecting the submission, provided that the technical report is not referenced in the submission. This allows authors to date their contribution if they wish.

Submitted papers must not appear in, be accepted for, or be under review for a journal or another peer-reviewed conference with archived conference proceedings at the paper submission deadline, that is at March 7. Submissions that have appeared at workshops or other meetings and have not been formally published or have appeared only in highly shortened form (e.g. abstracts) can be submitted as papers.

Each paper must be submitted to one track only (technical or application). When necessary, the Program Chair may move a submission to a more suitable track before reviewing starts.

Accepted papers will appear in conference proceedings published by LIPIcs, and follow the authors instructions guidelines. The proceedings will be available at the time of the conference.

Diversity Equity Inclusion (DEI) scholarship and other support

CP 2026 offers DEI scholarships to support individuals from underrepresented groups. These scholarships provide financial assistance to cover conference attendance costs, including registration fees, travel, and accommodation. Scholarship recipients have the option to be integrated into the Doctoral Program, where they will receive mentorship opportunities.

Eligibility for the DEI scholarship requires applicants to be pursuing or holding a PhD in constraint programming or related fields. Note that paper submission is not required to qualify for the scholarship. Applicants will be asked to provide a statement of eligibility, a motivation letter, and a short CV.

In addition to the scholarships, CP 2026 is willing to support attendees with childcare or accessibility needs on a best-effort basis; if you are interested, please get in touch early to discuss your needs. For more information, follow the DEI page and contact the DEI chairs.

Use of Generative AI

CP 2026 is adopting the AAAI policy regarding the use of Generative AI systems such as ChatGPT. Papers that include text generated from an AI system are prohibited unless the produced text is presented as a part of the paper’s experimental setup. This does not prohibit authors from using AI systems for editing or polishing author-written text.

CP 2026 also follows AAAI policy in considering that AI systems, including Generative Models such as Chat-GPT, BARD, or DALL-E, do not satisfy the criteria considered for paper authorship and, as such, these systems cannot be used as authors or as citable sources in papers published in CP. Authors assume full responsibility for the content of submitted work, including checking for plagiarism and the veracity of all text.

Inclusive Description of Research Contributions

Please consider making your research contribution description inclusive in nature. For example, consider using gender-neutral pronouns, using examples that are ethnicity/culture-rich, engaging users from diverse backgrounds if your research involves a survey, etc. To make the paper accessible to visually impaired and colour-blind readers, your paper should be still readable when printed in grey scale. To achieve this, most printing should be in black and white, and you should use patterns, symbols and textures to emphasise and contrast visual elements in graphs and figures.

Other Information

Questions about the paper submission process may be addressed to the Program Chair, Nicolas Beldiceanu (progchair.cp@gmail.com).

PhD + Postdoc positions on SAT-based machine learning at the University of Helsinki

Mon, 12 Jan 2026 00:00:00 +0100

One PhD student (4-year position) and two postdocs (3-year positions) to work on logic and machine learning are offered at the University of Helsinki:

The PhD and Postdoc 1 positions are on fundamental research in logic-based machine learning, focusing on using SAT/ASP/MaxSAT solvers.

Postdoc 2 focuses on developing logic-based methods for the Abstraction and Reasoning Corpus (ARC), also using solvers.

There are also postdoc positions funded via ELLIS Finland.

Please feel to email Andrew Cropper for more information: andrew.cropper@helsinki.fi.

SAT 2026 Second Call for Papers (Updated Deadlines)

Fri, 09 Jan 2026 00:00:00 +0100

AT A GLANCE

29th International Conference on Theory and Applications of Satisfiability Testing
ISCTE, Lisbon, Portugal, 20-23 July, 2026
Abstract registration deadline: 27 February, 2026
Submission deadline: 6 March, 2026
Conference website: https://satisfiability.org/SAT26/
Submission link: https://submissions.floc26.org/sat/

SUMMARY OF CALL FOR PAPERS

[Submission deadlines have been updated]

(Please note that this is just a summary — see the full call with all the details.)

SAT 2026 will take place 20-23 July, 2026 in Lisbon, Portugal at ISCTE, as part of FLoC 2026.

Scope

SAT 2026 is the 29th edition of the International Conference on Theory and Applications of Satisfiability Testing. The scope of SAT 2026 includes all aspects of the theory and applications of propositional satisfiability, broadly construed. This includes Boolean optimization, such as MaxSAT and Pseudo-Boolean (PB) constraints, Quantified Boolean Formulas (QBF), Satisfiability Modulo Theories (SMT), model counting, and Constraint Programming (CP), and integer linear programming (ILP) for problems with clear connections to Boolean-level reasoning.

Topics of interest for the SAT 2026 conference include (but are not limited to):

Theoretical advances (including algorithms, proof complexity, parameterized complexity, and other complexity issues)
Practical search algorithms
Knowledge compilation
Implementation-level details of SAT solving tools and SAT-based systems
Problem encodings and reformulations
Applications (including both novel applications domains and improvements to existing approaches)
Case studies and reports on insightful findings based on rigorous experimentation

Paper Categories

Submissions to SAT 2026 are invited in the following three categories:

Long papers (9 to 15 pages, excluding references and appendices)
Short papers (up to 8 pages, excluding references and appendices)
Tool papers (up to 8 pages, excluding references and appendices)

Submission

Submissions should not be under review elsewhere nor be submitted elsewhere while under review for SAT 2026, and should not consist of previously published material. Submissions not consistent with these guidelines may be returned without review.

Important Dates

Abstract Submission: ~~20 February~~ 27 February, 2026 (AoE)
Paper Submission: ~~27 February~~ 6 March, 2026 (AoE)
Rebuttal: 13-17 April, 2026
Author Notification: 30 April, 2026
Camera-ready Version: 14 May, 2026
Conference: 20-23 July, 2026

Proceedings

Accepted papers will be published as proceedings of the conference in the Leibniz International Proceedings in Informatics (LIPIcs) as a free, open, electronic archive with access to all. Authors will retain full rights over their work. The accepted papers will be published under a CC-BY license.

Full Call for Papers for SAT 2026

Please see https://satisfiability.org/SAT26/pages/cfp for the full call for papers.

PhD: Beyond resolution (University of Lleida)

Tue, 06 Jan 2026 00:00:00 +0100

Host: University of Lleida; Academic partner: University College Cork; Industry partner: OMP

The Satisfiability (SAT) problem, the first problem shown to be NP-complete, asks whether a Boolean formula in Conjunctive Normal Form has a satisfying assignment and is fundamental to computer science. SAT solvers have improved dramatically over recent decades due to techniques such as non-chronological backtracking and conflict-driven clause learning (CDCL), allowing modern solvers to handle industrial instances with hundreds of thousands of variables and millions of clauses.

More powerful SAT solvers can also improve Maximum Satisfiability (MaxSAT), the optimization version of SAT, which seeks to satisfy as many clauses as possible while distinguishing between hard and soft constraints. SAT-based MaxSAT algorithms repeatedly invoke a SAT solver to test bounds on the optimum. This thesis conjectures that significant progress in core-guided MaxSAT solvers (a family of MaxSAT solvers) requires selecting effective core sequences rather than merely optimizing search within a fixed sequence. Different core sequences can lead to vastly different performance, including exponentially harder instances, making their avoidance essential. In this thesis, we aim to design meta-algorithms that efficiently explore and select favorable core sequences.

Finally, gadgets allow us to transform a SAT instance into a Max2SAT instance for use with MaxSAT solvers. The combination of such gadgets with MaxSAT algorithms can yield proof systems stronger than Resolution. In this thesis, we aim to build on these efforts by offering new insights into generating SAT-to-Max2SAT gadgets that can be exploited more efficiently by MaxSAT solvers.

To demonstrate impact beyond benchmarks, the project will apply these techniques to challenging mathematical and industrial problems.

SAT 2026 Call for Papers

Fri, 12 Dec 2025 00:00:00 +0100

AT A GLANCE

29th International Conference on Theory and Applications of Satisfiability Testing
ISCTE, Lisbon, Portugal, 20-23 July, 2026
Abstract registration deadline: 20 February, 2026
Submission deadline: 27 February, 2026
Conference website: https://satisfiability.org/SAT26/
Submission link: https://submissions.floc26.org/sat/

SUMMARY OF CALL FOR PAPERS

(Please note that this is just a summary — see the full call with all the details.)

SAT 2026 will take place 20-23 July, 2026 in Lisbon, Portugal at ISCTE, as part of FLoC 2026.

Scope

Topics of interest for the SAT 2026 conference include (but are not limited to):

Theoretical advances (including algorithms, proof complexity, parameterized complexity, and other complexity issues)
Practical search algorithms
Knowledge compilation
Implementation-level details of SAT solving tools and SAT-based systems
Problem encodings and reformulations
Applications (including both novel applications domains and improvements to existing approaches)
Case studies and reports on insightful findings based on rigorous experimentation

Paper Categories

Submissions to SAT 2026 are invited in the following three categories:

Long papers (9 to 15 pages, excluding references and appendices)
Short papers (up to 8 pages, excluding references and appendices)
Tool papers (up to 8 pages, excluding references and appendices)

Submission

Important Dates

Abstract Submission: 20 February, 2026 (AoE)
Paper Submission: 27 February, 2026 (AoE)
Rebuttal: 13-17 April, 2026
Author Notification: 30 April, 2026
Camera-ready Version: 14 May, 2026
Conference: 20-23 July, 2026

Proceedings

Full Call for Papers for SAT 2026

Please see https://satisfiability.org/SAT26/pages/cfp for the full call for papers.

PhD: SAT-based Constrained Sampling for Crystal Structure Prediction (University of Liverpool)

Wed, 03 Dec 2025 00:00:00 +0100

We are inviting applications for a PhD studentship in Computer Science at the University of Liverpool, starting 1 October 2026 (apply by 15 January 2026).

The studentship is part of the EPSRC Centre for Doctoral Training in Digital and Automated Materials Chemistry, offering cohort-based training and access to a large interdisciplinary community working on digital and automated methods for materials discovery.

The project develops logic-based constrained sampling methods (SAT/SMT-style encodings, approximate uniform sampling) to generate chemically sensible, unbiased starting structures for crystal structure prediction (CSP) workflows.

The project will focus on:

logical encodings of chemistry constraints
SAT-based sampling to generate structures
integrating samplers into CSP workflows
comparing with generative AI and heuristic approaches

This is a CS-heavy project at the chemistry/CS interface. A background in SAT/SMT, formal methods, or related areas is highly relevant; no prior chemistry knowledge is required.

Further details and application instructions:
Crystal Structure Generation by Constrained Combinatorial Sampling – University of Liverpool

Informal enquiries: Friedrich Slivovsky.