Haskell Weekly

Welcome to another issue of Haskell Weekly! Haskell is a safe, purely functional programming language with a fast, concurrent runtime. This is a weekly summary of what’s going on in its community.

Featured

• GHC 9.6.2 is now available by Ben Gamari

  The GHC developers are happy to announce the availability of GHC 9.6.2. This release is primarily a bug-fix release addressing a few issues found in 9.6.1.

• GHC 9.2.8 is now available by Zubin Duggal

  The GHC developers are happy to announce the availability of GHC 9.2.8. This release is primarily a bugfix release addressing one issue found in 9.2.7.

• Haskell: Indexed Recursion Schemes by Leo Dillinger

  Today, we are going on a deep dive to show how recursion schemes may be extended by the addition of indexing.

• Haskell Optimization Handbook by Jeffrey M. Young

  This book is written as a handbook for the intrepid Haskell developer. It attempts to make clear aspects of the GHC-based Haskell so that performance optimizations and recommendations are actionable, rather than mysterious invocations whispered around the internet.

• Programming requires breadth of knowledge by Chris Martin

  For readers who haven’t figured it out already, my shtick is arguing that the pragmatic experience of Haskell doesn’t have to be substantially different from any other language. Here I want to combat the notion that learning Haskell is primarily about grasping some hard core concepts.

Jobs

• Assistant Computer Science Professor at Chalmers

Trying to hire a Haskell developer? You should advertise with us!

In brief

• Competitive programming in Haskell: introduction to dynamic programming by Brent Yorgey

  In this problem, we are given a sequence of opening and closing brackets (parens, square brackets, and curly braces) with question marks, and have to compute the number of different ways in which the question marks could be replaced by brackets to create valid, properly nested bracket sequences.

• Episode 26: Simon Marlow by The Haskell Interlude

  Simon is a long time GHC contributor, currently working at Meta. He talks about compiling functional languages via C and the Evil Mangler, the importance of using parallelism and its impact on garbage collection, and about using Haskell in the real world via Sigma, Haxl, and Glean.

• Episode 27: Christiaan Baaij by The Haskell Interlude

  Christiaan talks about his work on the Clash compiler, what it is like to found your own company, his desire for ergonomic dependent types, and the foundations to all his success, namely capitalising unlock.

• Haskell Foundation DevOps Weekly Log, 2023-05-31 by Bryan Richter

  This log only covers the last couple days instead of a full week, but luckily I had some wrap-up tasks that I could dive into after my break.

• The Haskell Unfolder Episode 4: falsify by Andres Löh

  In this episode, Edsko will give a user’s perspective on falsify, his new library for property based testing in Haskell, inspired by the Hypothesis library for Python.

• Monthly Hask Anything (June 2023)

  This is your opportunity to ask any questions you feel don’t deserve their own threads, no matter how small or simple they might be!

• Monthly Update On A Haskell Game Engine

  What started as a weekend jam ended as a month-long death march, nothing new here

• Registration for free online participation in 2023 GHC Contributor’s Workshop by David Christiansen

  The event will be held on 7-9 June, 2023, and there’s a brief registration form for free remote participation that’s due by 5 June.

Show & tell

• Antikythera by Josep Bigorra

  Antikythera, named in honor of the first computer in history, is a tool to help you achieve a reproducible configuration, whatever that may mean for your use-case, and in the context you use it.

• fints2ledger by Moritz Rumpf

  I wrote myself a tool to download financial transactions from my bank and put them into a ledger journal.

• Reflex Platform version 1.0.0.0 by Sean Chalmers

• streamly version 0.9.0 by Harendra Kumar

  This release did a major revamp of the API to make it easier to comprehend and less error prone to use.

• TimeLoop by Corentin Dupont

  This is a demonstrator for studying time travel in a simple setting. The application will generate and display all the possible trajectories in a universe, in presence of time travel.

Call for participation

• swarm: Syntax/type errors should be ephemeral