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

• Bound by a Free-Monad-like Structure by Dennis Gosnell

  This post explains a little background for bound, and then shows my own definition using the free-monad-like structure.

• Learn Contravariant in 5 minutes by Jason Shipman

  There is another “mapping” typeclass out there - Contravariant - that we likely don’t bump into as often as Functor.

• Summer of Haskell 2023 Project Selections by Aaron Allen

  Summer of Haskell 2023 is off to a great start and we have some exciting news to share! We received many quality proposals from which to choose and our mentors have made their selections.

• Tidal 2.0 beatMode (TidalCycles vs TidalBeats?) by Alex McLean

  I’ve been rewriting Tidal again for a while but resisting actually using it, mostly out of a weird sense of delayed gratification.

• Working with Haskell CallStack by Matt Parsons

  GHC Haskell provides a type CallStack with some magic built in properties. Notably, there’s a constraint you can write - HasCallStack - that GHC will automagically figure out for you.

Jobs

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

In brief

• Haskell Foundation April 2023 Update by David Christiansen

• Haskell GitHub Trust is for Other People’s Packages by James Brock

  The Haskell GitHub Trust is new GitHub organization for community maintenance of Haskell packages.

• Haskell in Production: CollegeVine by Gints Dreimanis

  In this article, we interview Fyodor Soikin from CollegeVine — an online platform that connects high school students with college admissions guidance and mentorship.

• New board members at the Haskell Foundation by Richard Eisenberg

  It’s my pleasure to announce that the Haskell Foundation has selected 4 new members of our community to join our board.

• New Hackage Server Features by Gershom Bazerman

Show & tell

• automation-service by Dave Della Costa

  automation-service is a tool for setting up simple-to-complicated home automations, like triggering lighting to go on when you enter a room, or reading from and responding to sensors — and much more.

• unleash-client-haskell by Eirik Meland & Even Brenden

  Unleash is an open-source feature flag management service. This is a client SDK for use with Haskell applications.

• yes-browser by Hamza Maimoune

  This is an experimental browser to explore the challenges posed by browsers and what they should be constituted of.

Call for participation

• hoff: Log git’s output somewhere when git commands fail
• pandoc: enable auto_identifiers for man reader
• rhine: Use hlint-scan?
• xmonad-contrib: X.L.ByWidth handle LayoutMessages