Haskell Weekly


Issue 144 2019-01-31

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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.


  • Hakyll Pt. 4 — Copying Static Files For Your Build by Robert Pearce

    This short hakyll tutorial will show you a simple way to copy static files over to your build folder.

  • Announcing Floskell by Enno Cramer

    Floskell is a new Haskell source code formatter. Floskell tries to be flexible, meaning that the user should be able to tune the output to match their personal style preference.

  • Defining exceptions in Haskell by Chris Done

    Let’s talk about exceptions. They’re not perfect in Haskell. They’re not perfect in any language, really. We’re always making adjustments to what we think is the best way to handle exceptional circumstances.

  • Fractals and Monads — Part 2 by Derek Wise

    Last time I discussed the power set monad and how it shows up in certain methods of building fractals. This time I’ll go a bit further, and also explain some Haskell code I actually use to generate fractal pictures.

  • HLint Unused Extension Hints by Neil Mitchell

    HLint has detected unused LANGUAGE pragmas for a while - where you enable an extension (e.g. {-# LANGUAGE EmptyDataDecls #-}) but don’t use it. HLint v2.1.13 includes some improvements from Yair and myself making these hints even more powerful.

  • Visualizing Prequel Meme Prefix Tries with Recursion Schemes by Justin Le

    Not too long ago, I was browsing the prequel memes subreddit when I noticed that a fad was in progress constructing tries based on quotes as keys indexing stills from the movie corresponding to those quotes.


  • Galois is Hiring! (ad)

    Galois is looking for Software Engineers/Researchers and Project Managers! We collaborate with organizations like NASA, DARPA, and Amazon Web Services to explore blue sky ideas and turn them into usable technology. Some of the things we’ve worked on in the past: Formal methods, static analysis, binary analysis, cryptographic algorithms, domain specific languages, programming languages theory, abstract interpretation, type theory, formal verification and software correctness, reinforcement learning, autonomous systems assurance, communication security, cyber-deception for network defense, DDoS defense, provable hardware security, statistical anomaly detection for detecting advanced persistent threats. We think working here is awesome (see https://lifeatgalois.com).

  • Senior Haskell Engineer at Habito in London

    We are looking for a full-time senior engineer to join our team of full-stack engineers. Our core development values are strong, static typing and correctness, rigorous automation and everyone having a say.

In brief

Package of the week

This week’s package of the week is Silently, a library that allows you to prevent of capture writing to STDOUT and other handles.

Call for participation


North America



South America


  • 2019-02-03 in Bangalore, India by Bangalore Functional Programmers Meetup: Dependent Types