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GHC 9.6.7 is now available
by Luite Stegeman 24 Mar '25

24 Mar '25

The GHC developers are very pleased to announce the availability of GHC 9.6.7. Binary distributions, source distributions, and documentation are available at https://downloads.haskell.org/ghc/9.6.7 We hope to have this release available via ghcup shortly. GHC 9.6.7 brings number of fixes, including: - GHC’s internal Unique type has been widened to 64-bits on 32-bit architectures, avoiding potential miscompilations on large projects. - Fix a runtime crash when using the compacting GC, caused by black holes in large objects. - Added new flags -fspec-eval and -fspec-eval-dictfun to allow switching off speculative evaluation. The following libraries have been updated since GHC 9.6.6: - base-4.18.3.0 - filepath-1.4.301.0 - unix-2.8.6.0 - bytestring-0.11.5.4 - array-0.5.8.0 A more detailed description can be found in the [release notes] and a full list of changes in [GHC!13841] and [GHC!13891] Note about Haskell Language Server and building GHC 9.8+: The change of Unique to 64 bit [GHC#22010] adds the exported symbol ghc_unique_counter64 to the RTS. Unfortunately it's impossible to avoid this without breaking other things. If you encounter a linker error related to ghc_unique_counter64 when building GHC (or building a GHC-derived package like ghc-lib-parser) with GHC 9.6.7, you probably have to add this [fix] to the program you're building. We would like to thank GitHub, IOG, the Zw3rk stake pool, Well-Typed, Tweag I/O, Serokell, Equinix, SimSpace, the Haskell Foundation, and other anonymous contributors whose on-going financial and in-kind support has facilitated GHC maintenance and release management over the years. Finally, this release would not have been possible without the hundreds of open-source contributors whose work comprise this release. Please give this release a try and open a [ticket] if you see anything amiss. ~ Luite [release notes]: https://downloads.haskell.org/ghc/9.6.7/docs/users_guide/9.6.7-notes.html [GHC!13841]: https://gitlab.haskell.org/ghc/ghc/-/merge_requests/13841 [GHC!13891]: https://gitlab.haskell.org/ghc/ghc/-/merge_requests/13891 [GHC#22010]: https://gitlab.haskell.org/ghc/ghc/-/issues/22010 [fix] https://gitlab.haskell.org/ghc/ghc/-/merge_requests/13743 [ticket] https://gitlab.haskell.org/ghc/ghc/-/issues/new

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Thesis-Job: Find the best specification method
by lists0＠freea2a.de 22 Mar '25

22 Mar '25

Dear haskell-list, at Siemens Mobility I would like to improve our specifications. For that, I have the opportunity to teach the properties of our product to a student, and ask him/her to specify the product with more or less of the full power of current specification techniques. The goal for me is, to evaluate existing methods and find the best method. We work intensively with specifications, thus a big level of mathematical formalism can count, as long as the technical team likes to learn and use it. The job offering for a final thesis is at the end of the post. Beside that: What does the list think are methods that are fruitful in a commercial high-quality setting ? The implementation shall not or almost not be changed, we just want a system for test generation and analysis of the required (and hopefully correctly implemented) system. Thank you for your answers! #### Job-offering (German): https://jobs.siemens.com/careers?query=440671&pid=563156121392428&organizat… As part of your work, you can do the following tasks: Search and justify a selection of an existing textual specification method (Domain Specific Language or Framework in a proven programming language). Specify parts of our existing system with the selection and apply the specification, e.g. for test case generation or for the detection of system properties. Examine the practicality of the specification method for daily use. What do you bring? You are studying computer science or a similar field. You already have knowledge of syntax and semantics / specification methods. Ideally, you have knowledge of several imperative languages and knowledge of functional programming (e.g. Haskell, OCaml, ...). Knowledge of machine proving is an advantage. You have good German and English language skills. You can write the work in German, English or bilingual. If you would like to complete a mandatory internship in advance, this is also possible after consultation. -- Mein PGP-Schlüssel-Fingerabdruck: B3CD 2CB8 EC08 B6BD D82C 9BE1 F702 BF50 C4AF 179D oder 88E6 D1E7 9276 BC56 849C CF02 9F96 BE18 43FA 2CC0

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Haskell.org mailing list status
by Ben Gamari 20 Mar '25

20 Mar '25

Hi all, As you may have noticed, yesterday brought an unexpected influx of traffic from haskell.org's mailing lists. This was the result of fixing an interruption in mailing list message delivery which began in late February as a result of on-going infrastructure migration efforts. We are monitoring the situation to ensure that this issue does not recur but if you see anything amiss don't hesitate to contact admin(a)haskell.org. Thank you for your understanding and help! Cheers, - Ben

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Utrecht Summer School on Advanced Functional Programming
by Wouter Swierstra 20 Mar '25

20 Mar '25

# Call for Participation SUMMER SCHOOL ON ADVANCED FUNCTIONAL PROGRAMMING Utrecht, the Netherlands, 07 July – 11 July 2025 http://www.afp.school **Please register before June 15th ** ## ABOUT The Advanced Functional Programming summer school has been running for more than fifteen years. We aim to educate aspiring Haskell programmers beyond the basic material covered by many textbooks. The lectures will cover several more advanced topics regarding the theory and practice of Haskell programming, including topics such as: * lambda calculus; * lazy evaluation; * generalized algebraic data types; * type families and type-level programming; * concurrency and parallelism. The summer school will be held in Utrecht and consists of a mix of lectures, labs, and a busy social program. ## PREREQUISITES We expect students to have a basic familiarity with Haskell already. You should be able to write recursive functions over algebraic data types, such as lists and trees. There is a great deal of material readily available that covers this material. If you've already started learning Haskell and are looking to take your functional programming skills to the next level, this is the course for you. ## DATES Registration deadline: June 15th, 2025 School: 07 July – 11 July 2025 ## COSTS € 950 euro - Profession registration fee € 500 euro - Student registration fee € 200 euro - Housing fee We will charge a registration fee of €950 (or €500 for students) to cover our expenses. This fee includes all lunches, dinners, and coffee breaks - you won't need to budget much else besides your travel. If this is problematic for you for any reason at all, please email the organisers and we can try to offer you a discounted rate or a fee waiver. We have a limited number of scholarships or discounts available for students that would not be able to attend otherwise, especially for women and under-represented minorities. ## FURTHER INFORMATION Further information, including instructions on how to register, is available on our website: http://www.afp.school

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ZuriHac 2025 takes place 7-9 June, Registration Open
by Farhad D. Mehta 20 Mar '25

20 Mar '25

Dear Friends of Haskell, It is our pleasure to announce that ZuriHac 2025 will take place Saturday 7 June – Monday 9 June 2025 as a physical event at the Rapperswil-Jona campus of the OST Eastern Switzerland University of Applied Sciences. ZuriHac is the biggest Haskell community event in the world: a completely free, three-day grassroots coding festival co-organized by the Zürich Friends of Haskell and the OST Eastern Switzerland University of Applied Science. It is not your standard conference with papers and presentations, but features fantastic keynotes, hands-on tracks, hacking on many of your favourite projects, and of course lots of socializing! This year’s keynote speakers currently include Lennart Augustson (current holder of the record for most number of Haskell compiler implementations), Rebecca Skinner (author of “Effective Haskell”), and Brent Yorgey (of “Diagrams” and “Swarm” fame). Further keynote speaker and track announcements will be made on our website. For an idea of what to expect, have a look at last year’s schedule on https://zfoh.ch/zurihac2024/ and a video impression of last year’s event at https://youtu.be/SMIdDqZxrUk?si=Jvl1LpuanFJHglSC . We also welcome beginners or people unfamiliar to Haskell who are curious to learn more. There will be an organised beginners’ track as well as many mentors from the Haskell community happy to answer all your questions. ZuriHac Prelude: Two days prior to ZuriHac, the Haskell Foundation and OST will organize the Haskell Ecosystem Workshop (HEW) and the Haskell Implementors’ Workshop (HIW - formerly co-located with the ICFP) at the same venue. Details will be posted to the ZuriHac website as they become available. You can find more information about the event and register at https://zurihac.info <https://zurihac.info/>. The event is free for participants. This is only possible with the help of our generous supporters, who are currently: - The Haskell Foundation - IOHK - OST - Tweag - Well-Typed In case you would like to support ZuriHac, as a company or as an individual, please get in touch with us. We would be grateful. Bank details for monetary donations can be found at https://zfoh.ch/#donations. We hope to see you there! The Zurich Friends of Haskell

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CfP: GPCE 2025
by Jeremy Yallop 20 Mar '25

20 Mar '25

[GPCE is co-located with ECOOP rather than SPLASH this year, so the deadline is earlier than usual.] ========================================================= GPCE 2025 24th International Conference on Generative Programming: Concepts & Experiences -- 3-4 July, 2025, co-located with ECOOP Bergen, Norway CALL FOR PAPERS https://2025.ecoop.org/home/gpce-2025 ========================================================= The ACM SIGPLAN International Conference on Generative Programming: Concepts & Experiences (GPCE) is a programming languages conference focusing on techniques and tools for code generation, language implementation, and product-line development. This is the 24th edition of the conference, co-located with the ECOOP 2025 conference in Bergen, Norway. ================== Topics of Interest =================== GPCE seeks conceptual, theoretical, empirical, and technical contributions to its topics of interest, which include but are not limited to: * program transformation, staging, * macro systems, preprocessors, * program synthesis, * code-recommendation systems, * domain-specific languages, * generative language workbenches, * language embedding, language design, * domain engineering, * software product lines, configurable software, * feature interactions, * applications and properties of code generation, * language implementation, * AI/ML techniques for generative programming, * generative programming for AI/ML techniques, * low code / no code approaches. GPCE promotes cross-fertilization between programming languages and software development and among different styles of generative programming in its broadest sense. Authors are welcome to check with the PC chair whether their planned papers are in scope. =================== Paper Categories ==================== GPCE solicits four kinds of submissions: Full Papers: reporting original and unpublished results of research that contribute to scientific knowledge for any GPCE topics. Full paper submissions must not exceed 12 pages excluding the bibliography. Short Papers: presenting unconventional ideas or new visions in any GPCE topics. Short papers do not always contain complete results as in the case of full papers, but can introduce new ideas to the community and get early feedback. Note that short papers are not intended to be position statements. Accepted short papers are included in the proceedings and will be presented at the conference. Short paper submissions must not exceed 6 pages excluding the bibliography, and must have the text “(Short Paper)” appended to their titles. Tool Demonstrations: presenting tools for any GPCE topics. Tools must be available for use and must not be purely commercial. Submissions must provide a tool description not exceeding 6 pages excluding bibliography and a separate demonstration outline including screenshots also not exceeding 6 pages. Tool demonstration submissions must have the text “(Tool Demonstration)” appended to their titles. If they are accepted, tool descriptions will be included in the proceedings. The demonstration outline will only be used for evaluating the submission. Generative Pearls: are elegant essays about generative programming. Examples include but are not limited to an interesting application of generative programming and an elegant presentation of a (new or old) data structure using generative programming (similar to Functional Pearl in ICFP and Pearl in ECOOP). Accepted Generative Pearl papers are included in the proceedings and will be presented at the conference. Generative Pearl submissions must not exceed 12 pages excluding the bibliography, and must have the text “(Generative Pearl)” appended to their titles. =================== Paper Selection ===================== The GPCE program committee will evaluate each submission according to the following selection criteria: Novelty. Papers must present new ideas or evidence and place them appropriately within the context established by previous research in the field. Significance. The results in the paper must have the potential to add to the state of the art or practice in significant ways. Evidence. The paper must present evidence supporting its claims. Examples of evidence include formalizations and proofs, implemented systems, experimental results, statistical analyses, and case studies. Clarity. The paper must present its contributions and results clearly. ==================== Important Dates ==================== Abstract Submission: Wed 26 Mar 2025 Paper Submission: Wed 2 Apr 2025 Review Notification: Fri 9 May 2025 Author Response: Mon 12 May 2025 Final Notification: Mon 19 May 2025 Conference: Thu 3 - Fri 4 July, 2025 ===================== Organization ====================== PC Chair: Nada Amin, Harvard General Co-Chair: Sebastian Erdweg, JGU Mainz General Co-Chair: Amir Shaikhha, University of Edinburgh Publicity Chair: Jeremy Yallop, University of Cambridge ======================= PC Members ====================== Bernhard Rumpe, RWTH Aachen University Casper Bach Poulsen, University of Southern Denmark Cyrus Omar, University of Michigan Eli Tilevich, Virginia Tech Elisa Gonzalez Boix, Vrije Universiteit Brussel Geoffrey Mainland, Drexel University Georg Ofenbeck Guillaume Allais, University of Strathclyde Jeremy Yallop, University of Cambridge Judith Michael, RWTH Aachen University Julia Lawall, Inria Kenichi Asai, Ochanomizu University Klaus Ostermann, University of Tuebingen L. Thomas van Binsbergen, University of Amsterdam Lionel Parreaux, The Hong Kong University of Science and Technology Malte Lochau, University of Siegen Maryam Mehri Dehnavi, University of Toronto Michel Steuwer, Technische Universität Berlin Ondřej Lhoták, University of Waterloo Parisa Ataei, Cornell University Philiip Wadler, University of Edinburgh Robert Glück, DIKU, Dept. of Computer Science, Univ. of Copenhagen Ruby Tahboub, University of Illinois Urbana-Champaign Sandro Stucki, Amazon Prime Video Automated Reasoning Sheng Chen, UL Lafayette Shigeru Chiba, University of Tokyo Shoaib Kamil, Adobe Research Simon Fowler, University of Glasgow Tijs van der Storm, CWI Ulrik Pagh Schultz Lundquist, University of Southern Denmark Vadim Zaytsev, Universiteit Twente Walter Binder, Università della Svizzera italiana (USI) Yukiyoshi Kameyama, University of Tsukuba Zena Ariola, University of Oregon

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Midlands Graduate School - registration now open
by Graham Hutton 18 Mar '25

18 Mar '25

Dear all, Registration is now open for the Midlands Graduate School (MGS) in the Foundations of Computing Science, 7-11 April 2025, Sheffield, UK. Eight fantastic courses on category theory, type theory, coalgebra, semantics and more. Spaces are limited, so please register early to secure your place. Please share in your communities! Best wishes, Graham Hutton ========================================================== Midlands Graduate School 2025 7-11 April 2025, Sheffield, UK https://tinyurl.com/MGS-2025 BACKGROUND: The Midlands Graduate School (MGS) in the Foundations of Computing Science provides an intensive course of lectures on the mathematical foundations of computing. The MGS has been running since 1999, and is aimed at PhD students in their first or second year of study, but the school is open to everyone, and has increasingly seen participation from industry. We welcome participants from all over the world! COURSES: Eight courses will be given. Participants usually take all the introductory courses and choose additional options from the advanced courses depending on their interests. Invited course - Four Lectures on Proof-theoretic Semantics, David Pym Introductory courses - Category Theory, Thorsten Altenkirch - The Curry-Howard Correspondence, Anupam Das - Quantum Computing, Venanzio Capretta Advanced courses - Coalgebra, Paul Blain Levy - Linear Logic, Abhishek De and Charles Grellois - Modular Proofs in Isabelle/HOL, Chelsea Edmonds - Refinement Types in Haskell, Brandon Hewer REGISTRATION: The registration fee is £300 for academic participants, and £500 for industry participants. The fee includes all lecture courses and example classes, lunch and coffee breaks. The registration deadline is ** Monday 17th March **. Spaces are limited, so please register early to secure your place. SPONSORSHIP: We offer a range of sponsorship opportunities for industry (bronze, silver, gold and platinum), each with specific benefits. Please see the website for further details. ========================================================== — Professor Graham Hutton School of Computer Science University of Nottingham, UK http://www.cs.nott.ac.uk/~pszgmh This message and any attachment are intended solely for the addressee and may contain confidential information. If you have received this message in error, please contact the sender and delete the email and attachment. Any views or opinions expressed by the author of this email do not necessarily reflect the views of the University of Nottingham. Email communications with the University of Nottingham may be monitored where permitted by law.

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[ANN] Copilot 4.3
by Ivan Perez 17 Mar '25

17 Mar '25

Hi everyone!! We are really excited to announce Copilot 4.3 [1,2]. Copilot is a stream-based EDSL in Haskell for writing and monitoring embedded C programs, with an emphasis on correctness and hard realtime requirements. Copilot is typically used as a high-level runtime verification framework, and supports temporal logic (LTL, PTLTL and MTL), clocks and voting algorithms. Compilation to Bluespec, to target FPGAs, is also supported. Copilot is NASA Class D open-source software, and is being used at NASA in drone test flights. Through the NASA tool Ogma [3] (also written in Haskell), Copilot also serves as a runtime monitoring backend for NASA's Core Flight System, Robot Operating System (ROS2), FPrime (the software framework used in the Mars Helicopter). This release introduces several updates, bug fixes and improvements to Copilot: - Specifications now produce information about counterexamples when copilot-theorem is able to prove the property false. - We introduce a new Prop construct in copilot-core that captures the quantifier used in a property. - The What4 backend of Copilot theorem now produces an exception when trying to prove an existential property. The restriction of not being able to handle existentially quantified properties already existed, but due to information loss during the reification process, the quantifier was being lost and all properties to be proved via what4 were being treated as a universally quantified. - Several deprecated functions have been removed. - The installation instructions have been updated. - Compatibility with GHC 9.10 is now explicitly listed in the README. - Several typos have been fixed in comments and documentation. The new implementation is compatible with versions of GHC from 8.6 to 9.10. This release has been made possible thanks to key submissions from Ryan Scott (Galois) and Esther Conrad (NASA), the last of which is also a first-time contributor to the project. We are grateful to them for their timely contributions, especially during the holidays, and for making Copilot better every day. For details on this release, see [1]. https://github.com/Copilot-Language/copilot/releases/tag/v4.3. As always, we're releasing exactly 2 months since the last release. Our next release is scheduled for May 7th, 2025. We want to remind the community that Copilot is now accepting code contributions from external participants again. Please see the discussions and the issues in our github repo [4] to learn how to participate. Current emphasis is on using Copilot for full data processing applications (e.g, system control, arduinos, rovers, drones), improving usability, performance, and stability, increasing test coverage, removing unnecessary dependencies, hiding internal definitions, formatting the code to meet our new coding standards, and simplifying the Copilot interface. Users are encouraged to participate by opening issues, asking questions, extending the implementation, and sending bug fixes. Happy Haskelling! Ivan -- [1] https://github.com/Copilot-Language/copilot/releases/tag/v4.3 [2] https://hackage.haskell.org/package/copilot [3] https://github.com/nasa/ogma [4] https://github.com/Copilot-Language/copilot

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GHC 9.12.2 is now available
by Ben Gamari 14 Mar '25

14 Mar '25

The GHC developers are happy to announce the release of GHC 9.12.2. Binary distributions, source distributions, and documentation are available at [downloads.haskell.org] We hope to have this release available via `ghcup` shortly. This is a small release fixing a critical code generation bug, #25653, affecting some subword division operations. As always, GHC's release status, including planned future releases, can be found on the GHC Wiki [status]. We would like to thank IOG, the Zw3rk stake pool, Well-Typed, Tweag I/O, Serokell, Equinix, SimSpace, the Haskell Foundation, and other anonymous contributors whose on-going financial and in-kind support has facilitated GHC maintenance and release management over the years. Finally, this release would not have been possible without the hundreds of open-source contributors who contribute their code, tickets, and energy to the GHC project. As always, do give this release a try and open a [ticket] if you see anything amiss. [release notes]: https://downloads.haskell.org/ghc/9.12.2/docs/users_guide/9.12.2-notes.html [status]: https://gitlab.haskell.org/ghc/ghc/-/wikis/GHC-status [downloads.haskell.org] https://downloads.haskell.org/ghc/9.12.2 [ticket]: https://gitlab.haskell.org/ghc/ghc/-/issues/new

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Internship opportunity at NASA Ames Research Center -- Deadline Feb 28
by Ivan Perez 27 Feb '25

27 Feb '25

All, We have an opening for an internship opportunity at NASA Ames Research Center working on a Haskell project. The deadline is tomorrow Friday, Feb 28. I've posted the details here: https://www.reddit.com/r/haskell/comments/1ixmlei/haskell_internship_openin… Please have any students who qualify apply ASAP. Thanks, Ivan

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