- Haskell-Cafe - Haskell.org

The Leksah (Haskell) IDE for Windows, Linux & macOS
by Andrew Goh 14 Aug '26

14 Aug '26

Dear Haskell Cafe, There was the Leksah (Haskell) IDE about 10 to 12 years ago. I wonder if you chaps can bring it back for the Windows, Linux and maybe macOS platform. I have the GHCup toolchain installed after a few mistries, and set up VS Code for Haskell programming, but I still would really prefer the Leksah IDE (this time in native mode) instead. As for the macOS platform, there is a Haskell Mac for IDE that can be brought for under US$10. Lastly, why don't you allow Haskell users to subscribe to all Haskell mailing lists rather than go individaully to each one to do that. - Andrew

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re-implementing gracefulClose in the network library
by Kazu Yamamoto 13 Aug '26

13 Aug '26

Hello, I'm going to change the implementation of "gracefulClose" in the network library. If you have opinions, please speak up. https://github.com/haskell/network/pull/617 --Kazu

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Type-level Programming and Extensibility at The MCG! - Melbourne Compose Group - Thurs 20th of August
by John Walker 12 Aug '26

12 Aug '26

This month we are looking forward to **Viktor Dukhovni** taking us into the realm of practical type level programming. *The Talk* *Viktor Dukhovni - Types, Nats, and Wire Formats - Type-level Programming and Extensibility in the Haskell dnsbase Stub Resolver Library * The dnsbase stub resolver library, written in Haskell, is a modernised revision of Kazu Yamamoto's "dns" library (GHC 7.x 2010-06). The "dns" library modelled DNS records via an ADT, with discrete constructors for each support RR type. In "dnsbase" existential quantification replaces the fixed form ADT and additional type-level machinery is used to make the library's set of supported DNS types extensible at runtime. This talk will highlight some of the techniques that make this possible. *When and Where* Format: Strictly IRL When: Thursday 20th Aug 2026, 6:00pm – 8:00pm Where: Kathleen Syme Centre, Activity Room 2, Carlton (Melbourne Victoria, Australia) Arrive from 6:00 for chat and socialising, talks start start at 6:30pm. [Please RSVP via Luma](https://luma.com/8eywg8ed) . As always, newcomers welcome. *About Melbourne Compose Group* Melbourne Compose Group is the monthly in-person meetup for functional programmers in Melbourne, every 3rd Thursday of the month in Carlton. Hope to see you there :) -Ben Hutchison & John Walker

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ICFP'26 upcoming on August 24-29: register today!
by ICFP Publicity 10 Aug '26

10 Aug '26

ICFP'26: Call for Participation The 31st ACM SIGPLAN International Conference on Functional Programming (ICFP 2026) and affiliated events invite you to participate in a full week dedicated to functional programming! https://icfp26.sigplan.org Indianapolis, Indiana, USA; Aug 24-29, 2026 *Register here*: https://icfp26.sigplan.org/attending/registration ICFP Overview ICFP is a celebration of the art and science of functional programming, providing a forum for researchers and developers to engage on a variety of topics, from foundations to features, and from abstraction to application. The main conference will be August 25-27, with workshops, tutorials, and other co-located events on August 24, 28, and 29. The program this year includes 38 accepted papers, 4 student research presentations, 2 tutorials, 3 keynotes, and 12 co-located events. We are delighted to have three keynote speakers this year: Edward Lee (UC Berkeley), Lindsey Kuper (UC Santa Cruz), and Daan Leijen (Microsoft Research). Come join the official ICFP'26 Discord channel: https://discord.gg/icfp26 - Accepted Papers: https://icfp26.sigplan.org/track/icfp-2026-icfp-papers - Registration: https://icfp26.sigplan.org/attending/registration - Venue: Indiana University Indianapolis https://icfp26.sigplan.org/venue/icfp-2026-venue1 - Hotel Blocks: https://icfp26.sigplan.org/attending/hotel-blocks - Tutorials: https://icfp26.sigplan.org/track/icfp-2026-icfp-tutorials Keynotes Keynote speakers this year: - Edward Lee (UC Berkeley): "Deterministic Concurrency" - Lindsey Kuper (UC Santa Cruz): "Interpreters everywhere!" - Daan Leijen (Microsoft Research): "Efficient strong functional programming with effects and compiler guided reference counting" More info: https://icfp26.sigplan.org/track/icfp-2026-icfp-keynotes Co-Located Events There are several events co-located with ICFP: *Monday, August 24* - PLMW: https://icfp26.sigplan.org/home/PLMW-ICFP-2026 - HOPE: https://icfp26.sigplan.org/home/hope-2026 - miniKanren: https://icfp26.sigplan.org/home/minikanren-2026 - FARM: https://icfp26.sigplan.org/home/farm-2026 - OCaml watch party: https://icfp26.sigplan.org/home/ocaml-2026 *Tuesday-Thursday, August 25-27* - ICFP - Main conference *Friday, August 28* - Haskell (Aug 28-29): https://icfp26.sigplan.org/home/haskellsymp-2026 - Erlang: https://icfp26.sigplan.org/home/erlang-2026 - ML Family: https://icfp26.sigplan.org/home/mlfamilyworkshop-2026 - LOPSTR+PPDP (Aug 27-29): https://icfp26.sigplan.org/home/lopstr-ppdp-2026 *Saturday, August 29* - Haskell (Aug 28-29): https://icfp26.sigplan.org/home/haskellsymp-2026 - Scheme: https://icfp26.sigplan.org/home/scheme-2026 - FUNARCH: https://icfp26.sigplan.org/home/funarch-2026 - LOPSTR+PPDP (Aug 27-29): https://icfp26.sigplan.org/home/lopstr-ppdp-2026

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POPL 2027 Call For Tutorials
by Ningning Xie 04 Aug '26

04 Aug '26

Call For Tutorials https://popl27.sigplan.org/track/POPL-2027-tutorials#Call-For-Tutorials The 54th ACM SIGPLAN Symposium on Principles of Programming Languages (POPL 2027) will be held in Mexico City, Mexico. POPL provides a forum for the discussion of fundamental principles and important innovations in the design, definition, analysis, transformation, implementation and verification of programming languages, programming systems, and programming abstractions. Tutorials for POPL 2027 are solicited on any topic relevant to the POPL community. We particularly encourage submissions of introductory tutorials that make the research presented at POPL more accessible to the participants. Tutorials will be held from January 9th (afternoon) to the 11th. The expected length of a tutorial is either 1.5 or 3 hours, including questions and discussion (Q&A). Submission details - Deadline for submission: October 9, 2026 - Notification of acceptance: October 23, 2026 A tutorial proposal should provide the following information: - Tutorial title - Presenter(s), affiliation(s), and contact information - Length (1.5 hour or 3 hours) - 1-3 page description (for evaluation). This should include the objectives, topics to be covered, presentation approach, target audience, prerequisite knowledge, and if the tutorial was previously held, the location (i.e. which conference), date, and number of attendees if available. - 1-2 paragraph abstract suitable for tutorial publicity. - 1-paragraph biography suitable for tutorial publicity. Proposals must be submitted by email to Aws Albarghouthi (aws(a)cs.wisc.edu) and Alan Schmitt (alan.schmitt(a)inria.fr) with the subject line “POPL 2027 Tutorial Proposal: [tutorial name]”. The proposal should be attached as a PDF, docx, or txt file. Further information Any questions regarding POPL 2027 tutorials should be addressed to the workshops chairs, Aws Albarghouthi (aws(a)cs.wisc.edu) and Alan Schmitt (alan.schmitt(a)inria.fr)

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Richard Bird Distinguished Dissertation Award - Final Call for Nominations
by Graham Hutton (staff) 03 Aug '26

03 Aug '26

================================================================== FINAL CALL FOR NOMINATIONS Richard Bird Distinguished Dissertation Award 2025 Deadline: 31st August 2026 http://tinyurl.com/jfp-bird-award ================================================================= OVERVIEW The Journal of Functional Programming is pleased to establish the Richard Bird Distinguished Dissertation Award, to recognise an outstanding PhD dissertation in functional programming. Richard Bird (1943-2022) was one of the leading figures in functional programming. He was a Professor in Oxford, where he founded the Algebra of Programming group, and served as Director of the Computing Laboratory. Richard is renowned for his many books and pearls on functional programming, which set a lasting standard for clear and elegant writing. It seems fitting that an award be established in his name to further encourage these values in the field. The award includes a prize of £1,000. Funding for the prize is supported by a generous donation from Richard himself to further the cause of functional programming. CRITERIA Eligible dissertations must have been completed in 2025. Depending on the institution, this may be the date of the viva, corrections being approved, graduation ceremony, or otherwise. The award is open to all topics within the remit of JFP, with a particular emphasis on dissertations that reflect Richard's own values of clarity, simplicity and elegance. For a dissertation to be considered for the award it should: - Reach a high standard of exposition; - Make a noteworthy contribution to the subject; - Place the results in the wider context of computer science. NOMINATIONS Please submit the following information to the award chair, <graham.hutton(a)nottingham.ac.uk>, by 31st August 2026: - Two letters of support, explaining why the dissertation should be considered for the award. One letter should be from the advisor/supervisor, and one from an independent source with no conflict of interest with the candidate, such as an external examiner or other expert in the field. - A copy of the dissertation itself. AWARD COMMITTEE Graham Hutton (chair), University of Nottingham Matthew Flatt, University of Utah Jeremy Gibbons, University of Oxford François Pottier, INRIA Wouter Swierstra, University of Utrecht Ningning Xie, University of Toronto The JFP editors-in-chief serve as observers of the committee. ================================================================= 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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GHC 9.14.2-rc1 is now available
by Zubin Duggal 31 Jul '26

31 Jul '26

The GHC developers are very pleased to announce the availability of the release candidate for GHC 9.14.2. Binary distributions, source distributions, and documentation are available at [downloads.haskell.org][] and via [GHCup](https://www.haskell.org/ghcup/). GHC 9.14.2 is a bug-fix release fixing many issues of a variety of severities and scopes, including: * Fixed a CorePrep miscompilation that could project a field out of an absent dictionary, resulting in a segfault (#25924) * Fixed demand analysis giving an absent demand to an argument that was still used by the function's stable unfolding, which could cause a run-time crash (#26416) * Numerous fixes for register allocation and Cmm register-conflict analysis bugs, preventing incorrect code generation and corruption of vector registers when spilling and reloading (#26411, #26526, #26537, #26542, #26550, #26668) * Many NGG fixes on AArch64: `MOVK` clobbering live values (#26980), register clobbering and an incorrect overflow bit in `MUL2` (#27046, #27047), and incorrect sign extension (#26978) and unsigned right shift (#26979) at sub-word widths * Fixed several black hole handling bugs that could lead to deadlocks or crashes in multithreaded programs, showing up as hangs or "END_TSO_QUEUE object entered" errors (#26922, #26936) * Fixed a stack alignment bug on x86 that could cause segfaults or corrupted registers when using AVX/AVX-512 vector code (#26595, #26822) * Fixed an "unknown/strange object" crash in the compacting garbage collector (#27434) * Fixed a regression that caused overloaded functions to no longer be specialised as effectively as in previous releases, hurting runtime performance (#26831) * Fixed exponential-time desugaring of nested `case` expressions (#27383, #20251) * Fixes for several compiler panics, including issues with SetLevels (#26681), the type-class specialiser (#26682), `mkTick` (#26772, #27121) and CoreToStg (#27182, #27386) * Fixed cast worker/wrapper incorrectly firing on INLINE functions (#26903) * Fixed negative type literals causing the compiler to hang (#26861) * Fixed associated type family and data family instance changes not triggering recompilation (#26183, #26705) * Improvements to determinism of compiler output, including the order in which `:info` lists instances (#26846, #26858, #26877, #27532) * Fixed split sections support on Windows (#26696, #26494) and the LLVM backend (#26770) * The JavaScript backend now supports more than 128 registers, fixing runtime `ReferenceError` failures for functions taking very many arguments (#26558) * Fixes for the Wasm backend, and the RISC-V and PowerPC native code generators * ... and many more A full accounting of these fixes can be found in the [release notes][]. As always, GHC's release status, including planned future releases, can be found on the GHC Wiki [status][]. This release candidate will have a two-week testing period. If all goes well the final release will be available the week of 13 August 2026. GHC development is sponsored by: * [Juspay](https://juspay.com/) * [QBayLogic](https://qbaylogic.com/) * [Channable](https://www.channable.com/) * [Haskell Foundation](https://haskell.foundation/) * [Serokell](https://serokell.io/) * [Well-Typed](https://well-typed.com/) * [Tweag](https://www.tweag.io/) * [Dotcom-Monitor](https://www.dotcom-monitor.com/) * [LoadView](https://www.loadview-testing.com/) * [Web Hosting Buddy](https://webhostingbuddy.com/) * [Find My Electric](https://www.findmyelectric.com/) * [Standard Chartered](https://www.sc.com) * [UpCloud](https://upcloud.com) * [Mercury](https://mercury.com) We would like to thank these sponsors 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. As always, do give this release a try and open a [ticket][] if you see anything amiss. [release notes]: https://gitlab.haskell.org/ghc/ghc/-/blob/ghc-9.14/docs/users_guide/9.14.2-… [status]: https://gitlab.haskell.org/ghc/ghc/-/wikis/GHC-status [downloads.haskell.org] https://downloads.haskell.org/ghc/9.14.2-rc1 [ticket]: https://gitlab.haskell.org/ghc/ghc/-/issues/new

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2026 Haskell Workshop Videos Now Online
by Dominik Schrempf 25 Jul '26

25 Jul '26

Dear haskell-cafe! We are happy to announce that the recordings from this year’s Haskell Implementors’ Workshop and Haskell Ecosystem Workshop are now available online. Both workshops were held on the lakeside campus of the University of Applied Sciences of Eastern Switzerland (OST) in Rapperswil on June 4th and 5th, alongside ZuriHac, and hosted by the Haskell Foundation. https://haskell.foundation/news/2026-07-18/hiw-hew-2026-videos.html Dominik

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LibreOffice gets LAMBDA expression
by Henning Thielemann 18 Jul '26

18 Jul '26

Simon Peyton Jones advocated for LAMBDA in Excel for long. Now we also get it in LibreOffice: https://gerrit.libreoffice.org/c/core/+/206265

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ICFP'26: Call for Participation and Early Registration Discount until July 25
by ICFP Publicity 17 Jul '26

17 Jul '26

ICFP'26: Call for Participation and Early Registration Reminder The 31st ACM SIGPLAN International Conference on Functional Programming (ICFP 2026) and affiliated events invite you to participate in a full week dedicated to functional programming! https://icfp26.sigplan.org Indianapolis, Indiana, USA; Aug 24-29, 2026 Early Registration Open Until July 25 *Register here*: https://icfp26.sigplan.org/attending/registration *Early registration discount* is available until *July 25*! ICFP Overview ICFP is a celebration of the art and science of functional programming, providing a forum for researchers and developers to engage on a variety of topics, from foundations to features, and from abstraction to application. - Accepted Papers: https://icfp26.sigplan.org/track/icfp-2026-icfp-papers - Registration: https://icfp26.sigplan.org/attending/registration (Early registration discount available until *July 25*!) - Venue: Indiana University Indianapolis https://icfp26.sigplan.org/venue/icfp-2026-venue1 - Hotel Blocks: https://icfp26.sigplan.org/attending/hotel-blocks - Tutorials: https://icfp26.sigplan.org/track/icfp-2026-icfp-tutorials Keynotes Keynote speakers this year: - Edward Lee (UC Berkeley): "Deterministic Concurrency" - Lindsey Kuper (UC Santa Cruz): "Interpreters everywhere!" - Daan Leijen (Microsoft Research): "Efficient strong functional programming with effects and compiler guided reference counting" More info: https://icfp26.sigplan.org/track/icfp-2026-icfp-keynotes Co-Located Events There are several events co-located with ICFP: *Monday, August 24* - PLMW: https://icfp26.sigplan.org/home/PLMW-ICFP-2026 - HOPE: https://icfp26.sigplan.org/home/hope-2026 - miniKanren: https://icfp26.sigplan.org/home/minikanren-2026 - FARM: https://icfp26.sigplan.org/home/farm-2026 *Tuesday-Thursday, August 25-27* - ICFP - Main conference *Friday, August 28* - Haskell (Aug 28-29): https://icfp26.sigplan.org/home/haskellsymp-2026 - Erlang: https://icfp26.sigplan.org/home/erlang-2026 - ML Family: https://icfp26.sigplan.org/home/mlfamilyworkshop-2026 - LOPSTR+PPDP (Aug 27-29): https://icfp26.sigplan.org/home/lopstr-ppdp-2026 *Saturday, August 29* - Haskell (Aug 28-29): https://icfp26.sigplan.org/home/haskellsymp-2026 - Scheme: https://icfp26.sigplan.org/home/scheme-2026 - FUNARCH: https://icfp26.sigplan.org/home/funarch-2026 - LOPSTR+PPDP (Aug 27-29): https://icfp26.sigplan.org/home/lopstr-ppdp-2026

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