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Ph.D. positions at Portland State University
by Yao Li 11 Oct '22

11 Oct '22

Dear All, I am looking for Ph.D students (starting Fall 2023) who are interested in programming languages, formal verification, and/or interactive theorem proving to join my new group at Portland State University. I am a new assistant professor at Portland State University. My research aims to (1) advance the state of the art of verification on real-world software and (2) make verification easier to use from a programming languages perspective. You can find more information about me on my webpage: https://lastland.github.io/ Please feel free to drop me an email if you are interested or if you have any questions about my research, my group, or Portland State University. I'd appreciate it if you can help spread the word to whoever might be interested. Cheers, Yao Li, Ph.D., (He/Him) Assistant Professor, Computer Science Department, Portland State University

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LAST CALL: Agda Implementors' Meeting XXXI - Edinburgh, 10-16 November 2022
by Orestis Melkonian 10 Oct '22

10 Oct '22

--------------------------------------------------------------- Agda Implementors' Meeting XXXI *Last call* for participation http://wiki.portal.chalmers.se/agda/pmwiki.php?n=Main.AIMXXXI --------------------------------------------------------------- The 31st Agda Implementors' Meeting will take place in Edinburgh, Scotland from Thursday 10 November 2022 to Wednesday 16 November 2022. Note that AIMXXXI was initially planned for 2019 but got postponed due to COVID-19, whilst we had several online meetings XXXII-XXXV. The meeting will consist of: * Presentations concerning theory, implementation, and use cases of Agda and other Agda-like languages. * Discussions around issues related to the Agda language. * Plenty of time to work in, on, under or around Agda, in collaboration with other participants. Unfortunately, the EuroProofNet day we initially planned has been cancelled. *Registration deadline (extended): October 21st* To register for AIM XXXI, please fill out the form below and send it to Orestis Melkonian by email <orestis.melkonian(a)ed.ac.uk>, or simply edit the AIMXXI wiki page yourself. > --------------------------------------------------------------- > Registration form for Agda Implementors' Meeting XXXI > > Name: > > Title and optionally abstract (if you want to give a talk or lead a discussion): > > Suggestions for code sprints (optional): > > Dietary restrictions: > > Additional comments: > > --------------------------------------------------------------- More information is available at http://wiki.portal.chalmers.se/agda/pmwiki.php?n=Main.AIMXXXI Please spread the word about this meeting. Best regards, Orestis

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Request for Nominations to the GHC Steering Committee
by Joachim Breitner 06 Oct '22

06 Oct '22

Dear Haskell community, the GHC Steering committee is seeking nominations for one or more new members. The committee scrutinizes, nitpicks, improves, weighs and eventually accepts or rejects proposals that extend or change the language supported by GHC and other (public-facing) aspects of GHC. Our processes are described at https://github.com/ghc-proposals/ghc-proposals which is also the GitHub repository where proposals are proposed. In particular, please have a look at the bylaws at https://github.com/ghc-proposals/ghc-proposals/blob/master/committee.rst We are looking for a member who has the ability * to understand such language extension proposals, * to find holes and missing corner cases in the specifications, * foresee the interaction with other language features and specifications, * comment constructively and improve the proposals, * judge the cost/benefit ratio and * finally come to a justifiable conclusion. We look for committee members who have some of these properties: * have substantial experience in writing Haskell applications or libraries, which they can use to inform judgements about the utility or otherwise of proposed features, * have made active contributions to the Haskell community, for some time, * have expertise in language design and implementation, in either Haskell or related languages, which they can share with us. There is no shortage of people who are eager to get fancy new features into the language, both in the committee and the wider community. But each new feature imposes a cost, to implement, to maintain in perpetuity in GHC's code base, to learn, and to deal with its unexpected interaction with other features. We need to strike a balance, one that encourages innovation (as GHC always has) while still making Haskell attractive for real-world production use and for teaching. We therefore seek a balance of background, expertise, and views on the committee. Membership of the committee gives you the chance to influence the future direction of Haskell, and to serve the Haskell community. The committee’s work requires a small, but non-trivial amount of time, especially when you are assigned a proposal for shepherding. We estimate the workload to be around 2 hours per week, and our process works best if members usually respond to technical emails within 1-2 weeks (within days is even better). Please keep that in mind if your email inbox is already overflowing. To nominate yourself, please send an email to me (as the committee secretary) at mail(a)joachim-breitner.de until February 11th. I will distribute the nominations among the committee, and we will keep the nominations and our deliberations private. On behalf of the committee, Joachim Breitner -- Joachim Breitner mail(a)joachim-breitner.de http://www.joachim-breitner.de/

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Help test XDG support in cabal-install
by Troels Henriksen 06 Oct '22

06 Oct '22

Cabal, or more precisely cabal-install which is mostly known to Haskellers as the cabal command line program, recently merged a pull request that makes cabal support the XDG Basedir Specification. Previously, cabal would put all of its files in the ~/.cabal directory. Now the files are spread over multiple directories: * $XDG_CONFIG_HOME/cabal for the main configuration file. On Unix, this defaults to ~/.config/cabal. * $XDG_CACHE_HOME/cabal for downloaded packages and script executables. Defaults to ~/.cache/cabal on Unix. * $XDG_STATE_HOME/cabal for compiled libraries and other stateful artifacts. Defaults to ~/.local/state/cabal on Unix. * ~/.local/bin for executables installed with 'cabal install'. The advantage is mostly that cabal now behaves slightly more like other modern Unix tools. For example, it is easier to put all configuration files under version control if they’re all in the same subdirectory, and it is easier to delete all program caches when you’re low on disk space. This is obviously a rather invasive change. Does it mean that the next version of cabal will break your workflow? Maybe! But if so, it is not intentional. This change comes with what I hope is rather thorough backwards compatibility behaviour. Basically, if ~/.cabal exists, or $CABAL_DIR is set, the old behaviour of using a single unified directory will be maintained. And of course, most paths can still be configured manually in the configuration file. Still, because of the delicacy of a change like this, we’d like some external confirmation that cabal is still usable. This requires human trials. Therefore, if you are a human who uses cabal, please try installing the latest development version and see if it still works for you. If you want to try out the new XDG future, you can delete your ~/.cabal directory (possibly copying ~/.cabal/config to ~/.config/cabal/config first). I’ve been dogfooding this support for a over month, but I have no illusions about my usage covering the full feature space. Beyond whether cabal remains at all functional, I am personally curious whether the XDG simulacrum that is implemented on Windows is at all useful for Windows users, or whether it would be better for cabal to retain a single unified directory on that platform. Finally, on a meta note, this is my first contribution to Cabal. I previously heard horror stories about its code complexity, but I don’t think think they are warranted, at least not in the corner that I was touching. You certainly find relics of a long development process, including code necessary to support obsolete features (v1-build and sandboxes), but for a project its age and scope, I found the code both well structured and reasonably well documented. XDG support was added entirely by modifying cabal client code, without touching the Cabal library at all. -- \ Troels /\ Henriksen

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Tlon is hiring a Haskell developer as a Senior Platform Engineer
by Edward Amsden 04 Oct '22

04 Oct '22

Urbit (urbit.org) is a social OS for everyone, and Tlon (tlon.io) is the primary company building it. Currently, most people run their Urbit OS on their own machine, but this won’t work for the masses. People need an easy way to get onto the network, and Tlon Hosting is building the product and platform to provide that. We are committed to becoming the primary infrastructure company for Urbit, hopefully managing millions of Urbit instances (aka “ships”) in the future. You will be joining a small team that is laying the foundation to build an ambitious and profitable business, which means you can have a big impact, and not only at Tlon, but on Urbit at large. We are looking for an infrastructure and platform engineer that is capable of leading the development of the next iteration of the hosting system. Running many Urbit instances at scale is not easy, because each instance needs to be carefully monitored and most Urbit life-cycle tasks need to be fully automated. To that effect, we implemented our own Kubernetes operator and additional tooling, all of which are written in Haskell. The role we are hiring for will have a central place in the further buildout of the system. You will develop the basic primitives and APIs that other engineers use to create a full featured hosting product. Additionally, you will need to be able to think strategically about how to iterate on the hosting platform so that other people can build on top of Urbit without having to worry where and how most of the Urbit instances run. In other words, hosting will have to become the most reliable and fool-proof way of using Urbit. Urbit is written in its own programming language, Hoon, and the runtime is written in C. But the hosting platform code is all written in Haskell, and that is what we are hiring for. The position and team is 100% remote. Most of us work in Europe time zones, and we prefer UTC +- 3 hours, but we are flexible. We do multiple offsites every year where we get to spend time IRL as a team and with everyone else at Tlon. Compensation range is $140-190k base salary, plus benefits, plus sizable bonus. There is a slight difference in the comp package structure depending on whether you are in the US or not, but in dollar value it should come out the same. Job Posting: https://tlon.io/careers/senior-platform-engineer To apply, write us here: apply(a)tlon.io

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CFP for PEPM 2023 (Partial Evaluation and Program Manipulation)
by Edwin Brady 03 Oct '22

03 Oct '22

(Apologies for any duplicate copies) -- CALL FOR PAPERS -- ACM SIGPLAN Workshop on PARTIAL EVALUATION AND PROGRAM MANIPULATION (PEPM) 2022 =============================================================================== * Website : https://popl23.sigplan.org/home/pepm-2023 * Time : 16th--17th January 2023 * Place : Boston, Massachusetts, United States (co-located with POPL 2023) The ACM SIGPLAN Workshop on Partial Evaluation and Program Manipulation (PEPM) has a history going back to 1991 and has been co-located with POPL every year since 2006. It originated with the discoveries of useful automated techniques for evaluating programs with only partial input. Over the years, the scope of PEPM has expanded to include a variety of research areas centred around the theme of semantics-based program manipulation — the systematic exploitation of treating programs not only as subjects to black-box execution but also as data structures that can be generated, analysed, and transformed while establishing or maintaining important semantic properties. Scope ----- In addition to the traditional PEPM topics (see below), PEPM 2023 welcomes submissions in new domains, in particular: * Semantics based and machine-learning based program synthesis and program optimisation. * Modelling, analysis, and transformation techniques for distributed and concurrent protocols and programs, such as session types, linear types, and contract specifications. More generally, topics of interest for PEPM 2023 include, but are not limited to: * Program and model manipulation techniques such as: supercompilation, partial evaluation, fusion, on-the-fly program adaptation, active libraries, program inversion, slicing, symbolic execution, refactoring, decompilation, and obfuscation. * Techniques that treat programs/models as data objects including metaprogramming, generative programming, embedded domain-specific languages, program synthesis by sketching and inductive programming, staged computation, and model-driven program generation and transformation. * Program analysis techniques that are used to drive program/model manipulation such as: abstract interpretation, termination checking, binding-time analysis, constraint solving, type systems, automated testing and test case generation. * Application of the above techniques including case studies of program manipulation in real-world (industrial, open-source) projects and software development processes, descriptions of robust tools capable of effectively handling realistic applications, benchmarking. Examples of application domains include legacy program understanding and transformation, DSL implementations, visual languages and end-user programming, scientific computing, middleware frameworks and infrastructure needed for distributed and web-based applications, embedded and resource-limited computation, and security. This list of categories is not exhaustive, and we encourage submissions describing new theories and applications related to semantics-based program manipulation in general. If you have a question as to whether a potential submission is within the scope of the workshop, please contact the programme co-chairs, Edwin Brady (ecb10(a)st-andrews.ac.uk) and Jens Palsberg (palsberg(a)ucla.edu) Submission categories and guidelines ------------------------------------ Two kinds of submissions will be accepted: * Regular Research Papers should describe new results, and will be judged on originality, correctness, significance, and clarity. Regular research papers must not exceed 12 pages. * Short Papers may include tool demonstrations and presentations of exciting if not fully polished research, and of interesting academic, industrial, and open-source applications that are new or unfamiliar. Short papers must not exceed 6 pages. References and appendices are not included in page limits. Appendices may not be read by reviewers. Both kinds of submissions should be typeset using the two-column ‘sigplan’ sub-format of the new ‘acmart’ format available at: http://sigplan.org/Resources/Author/ and submitted electronically via HotCRP: https://pepm23.hotcrp.com/ Reviewing will be single-blind. Submissions are welcome from PC members (except the two co-chairs). Accepted regular research papers will appear in formal proceedings published by ACM, and be included in the ACM Digital Library. Accepted short papers do not constitute formal publications and will not appear in the proceedings. At least one author of each accepted contribution must attend the workshop (physically or virtually) and present the work. In the case of tool demonstration papers, a live demonstration of the described tool is expected. Important dates --------------- * Paper submission deadline : **Thursday 13th October 2022 (AoE)** * Author notification : **Thursday 10th November 2022 (AoE)** * Workshop : **Monday 16th January 2023 to Tuesday 17th January 2023** Best paper award ---------------- PEPM 2023 continues the tradition of a Best Paper award. The winner will be announced at the workshop. Programme committee ------------------- * Chairs: Edwin Brady (University of St Andrews, UK) Jens Palsberg (University of California Los Angeles, USA) * Nada Amin Harvard (USA) * Adam Barwell (Imperial College London, UK) * Nicolas Biri (Input Output Global) * David Castro-Perez (University of Kent at Canterbury, UK) * Cristina David (University of Bristol, UK) * Atsushi Igarashi (Kyoto University, Japan) * Yukiyoshi Kameyama (University of Tsukuba, Japan) * Geoffrey Mainland (Drexel University, USA) * Hila Peleg (Technion Israel Institute of Technology, Israel) * Casper Bach Poulsen (Delft University of Technology, Netherlands) * Sukyoung Ryu (KAIST, Korea) * Sven-Bodo Scholz (Radboud University Nijmegen, Netherlands) * Ilya Sergey (National University of Singapore, Singapore) * Satnam Singh (Groq Inc, USA) * Elena Zucca (University of Genova, Italy)

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Obtain cost-centers stacks from eventlog file
by Ruben Astudillo 27 Sep '22

27 Sep '22

Hello -cafe! I got some experience profiling memory leaks using -prof and the +RTS -hc -L350 --RTS option. This gives me a .hp file with samples done at regular intervals. I can feed this file to `hp2pretty`, get some nice graphs and when I identify a suspicious band, I can grep the .hp file to get the complete "cost-center stack" responsible for that band. Here is an example of one: (18514)unsafeCreate/take/hexString/withText/parseOptionalFieldWith<...> I have been trying to replicate this setup using the eventlog logging. I use +RTS -l-aug -hc --RTS to get the eventlog with user and GC events. I use `eventlog2html` to get better view of memory allocation per cost-center. The normalized view presents me with cost-centers at the right side where I can filter on them[1]. But those labels are just the "top" of the cost-center stack. In fact I don't think the whole cost-center stack is represented anywhere on the eventlog file. I can sort of get the structure of the cost-center stack from the .hp file. The labels identifying the cost-center are different between the two files. Is there a way to recover the complete cost-center stack purely from the eventlog file? Thanks in advance [1]: https://imgur.com/a/nXyCEpG -- Rubén. (pgp: 1E88 3AC4 89EB FA22)

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Munich Haskell Meeting, 2022-09-29 @ 19:30
by Leah Neukirchen 26 Sep '22

26 Sep '22

Dear all, This week, our monthly Munich Haskell Meeting will take place again on Thursday, September 29 at Cafe Puck(!) at 19h30. For details see here: http://muenchen.haskell.bayern/dates.html If you plan to join, please add yourself to this nuudel so we can reserve enough seats! It is OK to add yourself to the nuddel anonymously or pseudonymously. https://nuudel.digitalcourage.de/AtDC1Gfm99791KZ8 Everybody is welcome! cu, -- Leah Neukirchen <leah(a)vuxu.org> https://leahneukirchen.org/

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Haskell courses @ 47 Degrees Academy
by Alejandro Serrano Mena 26 Sep '22

26 Sep '22

Dear all, I’m happy to announce that we’ve released four video courses about different topics in Haskell, at https://academy.47deg.com/collections/haskell - Introduction to optics (beginner) - Discovering functors, monads, and applicative (beginner) - Type level programming (intermediate) - Generic programming (advanced) As far as I know, this is some of the first content in video about the more advanced techniques in the language, like data type promotion or constraint kinds. I hope you all enjoy it! We're happy to hear any feedback from you :)

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ProLaLa 2023 -- Programming Languages and the Law (Jan 15th 2023, Boston) : Deadline Oct 27th 2022
by Jonathan Protzenko 26 Sep '22

26 Sep '22

----------------------------------------------------------------------------------------- ProLaLa 2023 -- 2nd Workshop on Programming Languages and the Law Sunday Jan 15th, 2022 Boston, MA co-located with POPL 2023 ------------------------------------------------------------------------------------------ (please forward to anyone who might be interested!) We are pleased to announce ProLaLa'23, the second edition of the workshop concerned with the intersection of PL (Programming Languages) techniques and the law. We are particularly concerned with the following topics: - language design for legal matters; - static analysis of legal texts; - program synthesis and repair for legal software components; - formal modeling of legal semantics; - non-standard logics in support of legal reasoning; - program verification for legal expert systems. If you have explored any of these areas, we encourage you to submit a short abstract. We are hoping to solidify around this workshop what we believe is a nascent but growing community; last year we had 25 submissions and 60 participants. As such, the workshop will be informal, and we strongly encourage you to submit ongoing or already-published work in the form of a brief 5-page submission for a long talk, or a 2-page submission for a short talk. Full details: https://popl23.sigplan.org/home/prolala-2023#Call-for-Papers <https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpopl23.si…> Venue ProLaLa will be colocated with POPL'23. We plan to coordinate with the POPL conference on remote participation. We would like to have remote participation even if the workshop happens in person. Our plan is to create an inclusive environment that does not demand traveling for COVID-19 (or other) reasons. Submission details We accept two kinds of submissions. - Long talks: 5 pages excluding references - Short talks: 2 page excluding references We require using SIGPLAN's one-column LaTeX format (acmsmall). Submission site: https://prolala23.hotcrp.com <https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fprolala23…> Important dates - Thu 27 Oct 2022: Submission deadline - Thu 10 Nov 2022: Notification of acceptance - Sun 15 Jan 2023: Workshop Program committee - Shrutarshi Basu (co-chair), Middlebury College, USA - Denis Merigoux (co-chair), Inria, France - Jonathan Protzenko (co-chair), Microsoft Research, USA - Timos Antonopoulos, Yale, USA - Joaquín Arias, Universidad Rey Juan Carlos, Spain - James Grimmelman, Cornell, USA - Ekaterina Komandantskaya, Herriot-Watts University, UK - Emma Tosch, University of Michigan, USA - Saeid Tizpaz-Niari, University of Texas at El Paso, USA - Giovanni Sileno, University of Amsterdam, Netherlands - Chris Bailey, University of Illinois, USA - Laurence Diver, Vrije Universiteit Brussel, Belgium - Sarah Lawsky, Northwestern Pritzker School of Law, USA

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