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June 17th, 2018, ISSUE 226


Scala in 2018 - The State of Developer Ecosystem by JetBrains

Survey results are now available!
JetBrains (@jetbrains)
Referential Transparency

The benefit of this constraint might not be immediately visible, so in this post I want to expose my thoughts on this, and see what Referential Transparency can buy us.
Pierangelo Cecchetto (@pierangelocecc)
Combining ScalaCheck generators

ScalaCheck library comes with a wide variety of built-in generators, but let me show you how to combine them to make the library even more powerful.
Michał Gutowski (@ferret_of_doom)
Scalaz 8 IO vs Akka (typed) actors vs Monix (part 1)

Some people say that the IO/Task wrappers offer a viable replacement for Akka’s actors. But is that so? Can you really replace an Actor with an IO or Task? If yes, is it practical to do so? Does it offer any advantages? Let’s find out on some concrete examples!
Adam Warski (@adamwarski)
Use the decorator pattern for clean I/O boundaries

Decorators are a great compositional pattern allowing the different concerns that inevitably cluster around I/O boundaries to be neatly separated and recombined.
Ken Scambler (@KenScambler)
Scala - AnyVal meets Pattern Matching

Originally I planned this article to be about a niche mechanism I've found in akka typed which allows you to use Pattern Matching without allocating unnecessary objects on the heap. However while writing it I played a little bit with javap -c ... and I've learned than I have really incomplete knowledge about bytecode produced by scala compiler.
Paweł Włodarski (@PawelWlodarski)
Scala 2.13’s Collections

This article summarizes what is going to change from an end-user perspective.
Julien Richard-Foy (@julienrf)
Train using Keras-MXNet and inference using MXNet Scala API

n this tutorial, we will walk you through one of the use cases where you can design your model, train using Keras-MXNet, and run inference in production, for example on Spark.
Wei Lai (@RoyWei)
Recognising Handwritten Digits with Scala

The purpose of this post is twofold: I want to spread the word about doddle-model and present to the non-ML audience how the problem of recognising handwritten digits might be approached, in a highly intuitive, rather than technical, manner.
Nejc Ilenic (@nejcilenic)
Tutorial: Shared json model between scalajs and scala backend

ScalaJS + akka http + play json combined together to get a nice shared model.
Raphael Parree
Introducing Accessible Scala

A tool for blind and partially-sighted developers. One of its goals is to remove the noise introduced by various delimiters.
Guillaume Massé (@MasseGuillaume)
SIP Meeting Minutes - 18th May 2018

Open discussion about SIP role and transition with given evolution of Scala language, from Scala 2 to Scala 3. The conversation was prompted due to the wake of Martin Odersky’s keynote at Scala Days, Berlin 2018 introducing the future of Scala - Scala 3.
Interflow: Scala Native’s upcoming flow-sensitive, profile-guided optimizer

To address the abstraction gap between Scala’s high-level features and LLVM’s low-level representation, we developed our own interprocedural, flow-sensitive optimizer called Interflow.
Interflow contributors


Scala - Your First Programming Language - Part 18 - Anonymous & Partial Functions

Warning: there is so much syntactic sugar in this video that you might get diabetes! In this video we will learn what happens behind the scenes when we use (partial) function literals in Scala. We will learn about lambdas, function objects, anonymous classes, magic, partial functions and their use cases.
DevInsideYou (@DevInsideYou)
Scala - Your First Programming Language - Part 19 - Pattern Matching Unleashed

In this video we are going to talk about the most prominent kinds of patterns Scala has to offer. We will see examples of constant, variable, wild card, constructor, tuple, sequence patterns and all the ways to compose them. We will also see how to avoid the common beginner pitfalls, especially the ones related to the differences between the constant and variable patterns as well as the ones related to type erasure on the JVM.
DevInsideYou (@DevInsideYou)


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)
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)
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)
Scala in the City, June 27th, 2018, Brighttalk, London, UK

Our two speakers this month are Leszek Sliwko discussing Scala on 40-core HPC machine & Luka Jacobowitz discussing Oh, all the things you'll traverse.
Signify Technology (@Signify_Tech)


Alpakka Kafka Connector 0.21.1

Support for Kafka Transactions, Metadata, and flexible message types. Please make sure you're using the 0.21.1 hotfix!
Alpakka Kafka Connector contributors

log4cats and log4scalaz attempt to make referentially transparent logging a reality.
log4cats contributors
slinky 0.4.3

Write Scala.js React apps just like you would in ES6.
slinky contributors
GitHub - olafurpg/sbt-ci-release: sbt plugin to help automate releasing from Travis CI to Sonatype

sbt plugin to help automate releasing from Travis CI to Sonatype.
sbt-ci-release contributors
Akka 2.5.13

More convenient Java API for recover, recoverWith and recoverWithRetries, API changes in Akka Types plus some fixes.
Akka contributors

A pre-configured package of tools letting you start working with Scala right away.
JetBrains (@jetbrains)
bloop-frontend 1.0.0-M11

Scala build server and command-line tool for faster developer workflows.
bloop contributors
sbt-assembly 0.14.7

Minor enhancements and bugfixes.
Eugene Yokota (@eed3si9n)
Build Server Protocol v1.0.0

The idea behind the Build Server Protocol is to standardize the protocol for how build tools (servers) and IDEs (clients) communicate, so a single Build Server can be re-used in multiple IDEs, and IDEs can support build tools with minimal effort.
BSP contributors


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