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May 17th, 2018, ISSUE 222

READING

Product with Serializable

While I don’t think that Product or Serializable are particularly good abstractions, there’s a reason that I extend them.
Cody Allen
Scala Enumerations hell

Should you use Scala’s built-in scala.Enumeration class or write your own implementation based on sealed class objects? People have been talking about it forever. But almost everyone agrees that usage of scala.Enumeration leaves a very bad taste and furthermore, it has few major problems.
Yurii Gorbylov
Running Play on GraalVM

Graal is a Polyglot VM that can run multiple languages and can interop between them without any overhead. In this blog post I will go into details what this means for Scala and especially for Play Framework and what runtime characteristics the new VM has, when running Play on top of it.
Christian Schmitt
Tagless Final algebras and Streaming

An example of abstracting out streaming and effects from a Doobie-based repository.
Gabriel Volpe (@volpegabriel87)
10 Reasons to Learn Scala and FP - DZone Java

Interested in dabbling in functional programming? At least, moreso than what Java 8 brought to the table? Here's the case for learning Scala.
Javin Paul (@javinpaul)
Hacker News API Part 4

If you didn’t read the previous 3 posts about this little learning project (or as my son calls it writing the same boring program over and over), then don’t worry because this will be self-contained and an introduction to the Monix library and a couple of fun things you can do with it.
justinhj (@justinhj)
Announcing the 2018 Scala Developer Survey

How do you use Scala? How did you come to Scala, and where are you going with it? How should the Scala language, the Scala library ecosystem, and Scala tooling improve? What’s next for the Scala community?
Scala Center (@scala_lang)
Intent to adopt the Apache License 2.0 for Scala

By popular demand, we intend to change the license that Scala is distributed under from the 3-clause BSD License to the Apache License v2.0. You have until 10 August 2018 to raise any objections.
Jorge Vicente Cantero and Adriaan Moors
Features I want in an IDE

In this post, I break down the features I want in an IDE. I introduce seven categories of IDE features, describe their associated trade-offs and summarize my personal preferences.
Ólafur Páll Geirsson (@olafurpg)
Typelevel ecosystem: a high-level overview

Learn about cats, cats-effect, circe, fs2, http4s, doobie , and how these libraries fit together.
Jakub Kozłowski (@kubukoz)

PRESENTATIONS

Scala - Your First Programming Language - Part 16 - Inheritance

In this video we will learn about inheritance - a mechanism for achieving modular design which as a by product allows for code reuse even though the code reuse part is frowned upon lately. We will discuss semantic differences between inheritance and subtype polymorphism and learn about object-oriented design patterns such as the "Template method" pattern. We will also dive into visibility and inheritance modifiers.
DevInsideYou (@DevInsideYou)
Preparing for Scala 3

A summary of hot upcoming updates in Scala 3 vel Dotty.
Martin Odersky (@Odersky)

EVENTS

Lambda World Seattle, September 17th - 18th

Use promo code STLW18 for Scala Times readers to get 10% discount!
47 degrees (@47deg)
Lambda World Cádiz, Spain, October 25th - 26th, 2018

Use promo code STLW18 for Scala Times readers to get 10% discount!
47 degrees (@47deg)
Scala in the City, May 23rd, 2018, Concentra, London, UK

We will hear from Chris Birchall from OVO on Shapeless and Jamie Pullar from Concentra on Cats.
Signify Technology (@Signify_Tech)
WIN a ticket to Scala Days New York

Simply send us a blog you have written that you would like featured on our website!
Signify Technology (@Signify_Tech)
LX Scala, Lisbon, Portugal, June 8th, 2018

The greatest Scala Conference in Southwest Europe. Use discount code lx_scala_times to get a 20% discount for our readers!
e.near (@enearportugal)
Scala Wave, September 6th - 8th, 2018, Gdańsk, Poland

Use code scalatimes_10, registration with special 10% off discount, to use on the conference day, ends on June 30th!
Scalac (@scalawavepl)

RELEASES

testz

The pure testing library by scalaz.
testz contributors
sangria 1.4.1

A GraphQL library. Most recent spec changes, including `extend schema` in SDL, compatibility with GraalVM + a bunch of minor fixes and improvements.
Sangria contributors
sangria-http4s-graalvm-example

An example of GraphQL server built with sangria, http4s and circe which compiles and runs as a GraalVM native image.
Oleg Ilyenko (@easyangel)
Mantis 1.1

Scala Client for Ethereum Classic, The Daedalus Release.
Mantis contributors
circe-kafka

Implicit conversion of Encoder and Decoder into Serializer/Deserializer/Serde.
Tim Steinbach (@Tim_Steinbach)
Scala 2.13.0-M4

This is the first 2.13 milestone that includes the improved and simplified Scala collections library. We expect the API to mostly remain stable after this release, although there may still be minor changes in M5.
Scala contributors

VARIA

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