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March 29th, 2018, ISSUE 215


Tour of Akka Cluster: Testing with the multi-node-testkit and a handful Raspberry PIs

It is time to look at one feature that is extremely useful when it comes to building production-quality systems based on Akka Cluster: the test support.
Manuel Bernhardt (@elmanu)
Akka anti-patterns: overusing ActorSelection

Learn how to avoid problems caused by the facts that ActorSelection is unverified and less performant than ActorRef.
Manuel Bernhardt (@elmanu)
Twilio guardrail: Principled Code-Generation for Type-Safe Languages

A framework for providing principled code-generation in typesafe language and frameworks. We’ve initially targeted the Scala language, as well as Lightbend’s akka-http web framework, although experimental support for http4s clients has been added recently.
Devon Stewart
Google Summer of Code 2018 Scala Projects

Want to get involved? Here are some projects waiting for contributions: Mill Build Tool, Scalafix in the editor, scalajs-bundler 1.0, various features of CBT and Scala Native, Web-based test UI for Bloop and REPL modernisation.
Sequential Traverse for managing parallel resource usage in Scala

Using free monads to control the execution of asynchronous tasks in Scala.
James Phillips
CoRecursive w/ Adam Bell: 009 - Throw Away the Irrelevant with John A De Goes

We talk about performance problems with monad transformer on the jvm, various flavours of IO monads and reasoning about polymorphic type signatures. On the lighter side of things, we discuss how to write technical articles well, flame wars and Zee vs Zed pronunciation.
John A. De Goes (@jdegoes)


Dependency Inversion | Inversion of Control (IoC) For Absolute Beginners

Learn the basics of DI using Scala.
Programming vs Math

In this video we are going to discuss the differences between mathematical functions and functions in programming, which in my humble opinion should rather be called subroutines or procedures to avoid confusion.


ScalaUA, April 20-21, 2018, Kyiv, Ukraine

Use promo code "ScalaTimes_ScalaUA-2018-20-04" for 5% discount!
Scala Sphere, April 15-17, Kraków, Poland

Use promo code sphereit-2018-scalatimes for 10% discount for Scala Times readers!
Scala Sphere (@ScalaSphere)
Scalapeño 2018 CFP, July 2, Beer Sheva, Israel

Send your proposal before 2018.04.01.
Blockyard Conference, April 13, Gdańsk, Poland

Use our promo link to get a 40% discount for Scala Times readers!
Scalar Conference, Apirl 6-7, Warsaw, Poland

There are still some tickets available for the conference and accompanying workshops, so don't hesitate!
SoftwareMill (@scalarconf)


RasterFrames 0.6.0

RasterFrames brings the power of Spark DataFrames to geospatial raster data.
RasterFrames contributors
Ammonite 1.1.0

The first version with experimental Java 9/10 support and Windows support in the REPL (using JLine3).
Li Haoyi (@li_haoyi)
Mill 0.1.7

A new, reinvented Scala build tool. Now with better Windows & Java 9 support & tons of bugfixes.
Mill contributors

In the daily life of a strongly-typed language's programmer sometimes it happens we need to transform an object of one type to another object which contains a number of the same or similar fields in their definitions.
Chimney contributors
µPickle 0.6.2

A blazing fast Scala JSON library, ~3x faster than 0.5.1. uPickle now supports parsing to (and serializing) Other ASTs, from libraries such as Circe, Argonaut, Json4s or Play-Json.
uPickle contributors
IntelliJ Scala plugin 2018.1

Inline hints, better Structure View, improved refactoring, and greater usability | IntelliJ Scala plugin blog.
JetBrains (@jetbrains)
sbt 1.1.2 hotfix

A solid pack of improvements, bugfixes and internal changes.
sbt contributors


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