Haskell Weekly


Issue 239 2020-11-26

Subscribe now! We'll never send you spam. You can also follow our feed. Read more issues in the archives.

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.


  • 2020 State of Haskell Survey results by Taylor Fausak

    The fourth annual State of Haskell Survey closed last week. This post will graph the responses, analyze them, and compare them to previous years.

  • 2020 State of Haskell survey: an attempt at cluster analysis by Francesco Ariis

    This year I decided to attempt cluster analysis on the data.

  • Existential Haskell by Patrick Thomson

    In this piece, I’ll describe a common example of information hiding in ALGOL-style languages like Java, then express that in terms compatible with Haskell.

  • hs-to-coq and Data.Sequence by Li-yao Xia

    In this post, I will present some of the changes made in hs-to-coq to be able to translate Data.Sequence.

  • A Queue for Effectful Breadth-First Traversals by Donnacha Oisín Kidney

    We pick up the story again at the question of a breadth-first (Applicative) traversal of a rose tree.

  • Reducing the pain of grouping SQL query results using Haskell by Ben Levy & Christian Charukiewicz

    With a system written in Haskell, we can use the Semigroup typeclass and the append operation it exposes (<>) to transform the data into the shape we need by defining our desired custom data types and simple transformation functions.

  • A tale of Template Haskell and cross compilation by Cheng Shao & Georgios Karachalias

    It is less well known that Template Haskell also makes cross compilation with GHC harder.

  • URI Fragment support for Servant by Andrey Prokopenko

    I would like to have this feature available inside servant core package, since fragment is a part of URI and could be used on both server and client side.

  • Virtual Record Fields Using Lenses by Chris Penner

    Lenses are commonly used for getting and setting fields on records, but they’re actually much more adaptable than that!

  • Where We Build a Computer by Jeroen Bulters

    Since I’ve done some of the challenges last year, I know that there will be a rapid ramp-up in difficulty and that a number of challenges build “on top of each other”.


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

In brief

  • Haskell in the Real World by Sandy Maguire

    It’s rare that I actually get to use this stuff I spend so much time thinking about, so thought it would make a nice and quick blog post.

  • Testing the Watcher by Monday Morning Haskell

    In this video, we’ll explore how to simulate file modifications in the middle of a unit test.

  • Trying To Create Syntax Optics by Yair Chuchem

    The journey to create combinators for parsing and pretty-pretting continues!

Show & tell

Call for participation