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September 19th, 2019, ISSUE 292


Fixtures in Scala - three simple ways to reduce your test code boilerplate

Have you ever copied a very long test case just to change the name and few lines of code?
Jakub Dzikowski
Human-readable case class diffs

a short introduction to diffx library.
Kasper Kondzielski (@kkondzielski)
Why Parallel

Why someone using Cats should care about Parallel in the first place?
Travis Brown (@travisbrown)
Cats 2.0 migration guide

Which of the changes in the release 2.0 will affect users and what you can do about them?
Travis Brown (@travisbrown)
Top 10 Scala Libraries For Data Science

A tool-kit for every data science enthusiast.
Ambika Choudhury
Kenji Yoshida receives community award

The winner of the Phil Bagwell Memorial Scala Community Award.
Scala Lang Team
Kelley Robinson receives community award

The winner of the Phil Bagwell Memorial Scala Community Award.
Scala Lang Team
Considering Scala?

Find out if Scala is right for you and your team.
Oliver Winks (@OliWinks)
http4s: from Cats to ZIO

How http4s app runs with ZIO.
Alex Fruzenshtein (@Fruzenshtein)
Build your own Kafka in ZIO - ZIO Queues & ZIO Fibers

Queues & Fibers by example. A messaging system built step by step.
Mateusz Sokół
Functional tests with Scala, SBT, Play framework, Specs2 and one application per test suite

How to obtain an application using the WithApplication class of play-specs2 module?
Geovanny Junio
Cassandra scala client

How to use cassandra prepared statements with scala to do query operations?
λ.eranga (@itseranga)
Composing functions with Reader monad

A short tutorial on Reader Monad.
Alexander Zaidel
GoF design patterns in Scala: Visitor

The first episode from the classic patterns by the Gang of Four series.
Manuel Rodríguez
Top Link Of August: Scala Almost Succeeded

Sam's post really got our reader's attention last month, make sure you've read it too!
Sam Halliday (@fommil)


Getting started with Scalafmt

In this video we will install and play around with Scalafmt which is a code formatter for Scala.
DevInsideYou (@DevInsideYou)
The Traverse type class in Cats - Scala tutorial

In this video, you'll see what the Traverse type class is and what it allows you to do. You'll see some examples of traversable functors like List, Option and NonEmptyList, as well as applicative functors you can traverse to - IO, Option, Either, Validated and Map*.
Jakub Kozłowski (@kubukoz)


Scala.sphere.it, Kraków, Poland, October 7th-8th

Use special promo code 'media-partner-at-sphere.it' for a 20% discount.
ScalaSphere (@ScalaSphere)
Lambda World, Cádiz, Spain, October 17th - 18th

Use our link to get a special discount for Scala Times readers!
Lambda World (@lambda_world)
Code Mesh, London, November 7th - 8th

Get your tickets now!
CodeMesh (@CodeBEAMio)
BeeScala, Ljubljana, Slovenia, November 21st - 21rd

Don't miss your ticket for this unique conference!
BeeScala (@BeeScalaConf)
Tech Triveni, IIC Delhi, India, November 23rd - 24th

Grab special 10% discount code for Scala Times readers: TechTriveni10
Tech Triveni
CFP for ScalaConf.ru, Moscow, Russia, November 26th

Don't miss the CFP deadline which is September 26th!
Lambda Days, February 13th -14th 2020, Kraków, Poland

Call for talks and very early bird tickets are both open!
Lambda Days (@LambdaDays)
ScalaUA, April 3th-4th, 2020 Kyiv, Ukraine

CFP is on! Also: Super Early Bird tickets are available on website till 2019.12.31, and Wholesale 10+ tickets are available till 2020.04.02.
ScalaUA (@ScalaUA_Conf)


sbt-pgp 2.0.0

Breaking changes: Default to use GnuPG (useGpg := true); Bouncy Castle mode is now deprecated; camel case key name and package name change.
Eugene Yokota (@eed3si9n)

Scala library with simple-to-use utilites for students of introductory programming.
Bjorn Regnell
Scala 2.13.1

The release fixes several regressions in 2.13.0.
Scala contributors


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  1. Scala Times Issue #292

    Human-readable case class diffs. Cats 2.0 migration guide. Top 10 Scala Libraries For Data Science. Kenji Yoshida receives community award. Kelley Robinson receives community award.

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