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November 28th, 2019, ISSUE 302


Optional Actions

Sometimes, amongst required actions, we need to optionally do something. In this post we’ll see how we can use cats to concisely handle this situation.
Adam Rosien (@arosien)
Regexp Replacement via Function in Java/Scala

How to have fine grained control over replacements when using String.replaceAll or similar in Java or Scala.
Alex Nedelcu (@alexelcu)
Stryker Mutator

Kill the mutants. Test your tests with mutation testing.
Stryker Team
Rationality in a Natural World: Arithmetic at the Type-Level

In this article we are going to take a step beyond natural numbers, and derive a type-level encoding of (positive) rational numbers in Scala.
Jack Wheatley
Transforming Data with Embedded Spark

In this article we continue the exploration of Spark jobs written in Scala by building up on the foundation established in the previous article in this series.
Alec Lebedev
Migrate a service getting 200KQPS from Jackson to Circe

When you work with Finagle, handling JSON often means using Jackson, right? We decided to test another approach, more functional, with one of our production applications, and guess what? Works like a charm.
Alexandre Careil
Scala Type Classes comparison

In the second article we are going to compare Scala type class implementation with Java, Rust and Scala 3, which is new version of Scala compiler.
Alexey Novakov (@alexey_novakov)
Spark: Web Server Logs Analysis with Scala

In this article we will show you how simple it is to parse a web server log files and perform some analysis on it.
Achraf El Gdaouni
Prox part 2  - Aakka Streams with Cats Effect

In this post, we will keep cats-effect but replace fs2 with the stream library of the Akka toolkit, Akka Streams.
Daniel Vigovszky (@dvigovszky)
What can ZIO do for me?

Learn how sttp and ZIO make a great combo for polling scenarios.
Pascal Mengelt
"Functional Programming in Scala" and other great Manning books with a special discount!

An exclusive discount for our readers! Use promo code nltimes40 and get a 40% discount for all Manning products in any format!
Manning Books (@manningbooks)
IntelliJ Scala Plugin 2019.3

Method Chain Hints, Scala REPL, Scala Worksheet, and ScalaTest improvements.
JetBrains (@jetbrains)


How I set up all my SBT projects

In this video we are going to learn a few SBT tips and tricks and about several plugins that I use all the time in most if not all of my projects.
DevInsideYou (@DevInsideYou)
Build yourself an effect system

During this talk, we'll build a minimal effect runtime similar to the one used in ZIO.
Simon Schenk (@inoio_gmbh)


Lambda Days, February 13th -14th 2020, Kraków, Poland

Draft paper submission by January 13th.
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)
Scalar, March 19th-21st, 2020, Warsaw, Poland

Get ready for one of the biggest Scala conferences in Europe!
SoftwareMill (@scalarconf)



Boiler plate framework to use Spark and ZIO together.
Leo Benkel (@LeoBenkel)
Use := for Assignment

A hot discussion about whether or not the := operator should be adopted in Scala 3.
Martin Odersky (@Odersky)
ZIO Config

A functional, composable ZIO interface to configuration
ZIO Config contributors
Scala.js 1.0.0-RC1

This release candidate is intended for testing purposes by as many users as possible, and as a synchronization point with library authors so that they can start upgrading in preparation for the final release. If no critical issue is found until the end of January 2020, this RC will become the final release.
Scala.js contributors (@scala_js)


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