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November 22nd, 2018, ISSUE 249

READING

How To Exclude Scala Tests With Tagging?

If you want to disable certain types of tests with Scala you can use tags, here's an excellent summary of all the possibilities.
Dariusz Mydlarz (@dmydlarz)
Explore Witnesses as an Alternative to Implicits

Many developers consider implicits at least confusing. Here's a proposition of a new, cleaner concept.
Martin Odersky (@Odersky)
Build code analyzers with Scalameta and Scalafix

We are excited to announce the release of Scalameta v4.0.0 and Scalafix v0.9.0 introducing new APIs enabling more advanced source code analysis.
Ólafur Páll Geirsson, Eugene Burmako
Immutable State in Real World

Imperative programs use Statements that change the state of the program. Functional programs avoid changing state and mutable data.
Wiem Zine
A streaming library with a superpower: FS2 and functional programming

This library embodies all the advantages of functional programming (FP). By understanding its design goals you will get exposure to the core ideas that make FP so appealing.
Daniel Sebban (@dsebban)
Cats Effect Typeclasses cheat sheet

What is the relationship between bracket, lif IO, Async, Sync, Effect and other abstractions from Cats Effects? Learn with this cute cheat sheet.
Impure Pics
5 themes for Scala programming in 2018

As major tech conference programmes are built, themes can often emerge and become central to the discussions that occur. This has never been more obvious than for this year’s Scala eXchange London. Read more.
Skills Matter (@skillsmatter)

PRESENTATIONS

Homegrown Scala Collections - Part 14 - Rendering Trees

In this video we are going to implement a method on our Sets which will render the binary trees backing them. The output is inspired by the Linux "tree" command.
DevInsideYou (@DevInsideYou)

EVENTS

Scalar, Warsaw, Poland April 5-6, 2019

Join the next edition of the largest Scala conference in central Europe!
SoftwareMill (@softwaremill)
Lambda Days, Kraków, Poland, February 21-22, 2019

Use promo code SCALArlz10 for a 10% discount for our readers!
LambdaDays (@LambdaDays)
$100 discount for Scala Times readers for "Functional Scala" training by John A De Goes in London

Use code "ScalaTimes" and join the training on Dec 10-12.
Signify Technology (@Signify_Tech)
What are the experts keen to share at Scala eXchange London 2018

“A conference is more than just a series of talks. It's about community, friendship, and having fun. You can't replicate that by watching videos." - Noel Welsh on why he is speaking at ScalaX again this year. Check out what others amazing speakers are most looking forward to the conference! Read more.
Skills Matter (@skillsmatter)

LISTENING

Big Ball Of Mud - Architecture and Services with Wade Waldron

Software that is providing value often grows in scope until it is a mess. Today I talk to Wade Waldron about how avoid this situation or recover from it.
Corecursive Podcast with Adam Bell

RELEASES

Fury

Fury is an experimental dependency manager and build tool for Scala. It is still under active development, and is in private beta.
Jon Pretty (@propensive)
skunk

A data access library for Scala + Postgres.
Rob Norris (@tpolecat)

VARIA

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