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July 26th, 2018, ISSUE 232


Akka anti-patterns: Java serialization

Performance is one reason to not use Java serialization – but there are stronger reasons to not engage with it, especially in the context of Akka.
Manuel Bernhardt (@elmanu)
Practical Cats: Functor and Applicative

In this post, I ’m going to introduce you some useful aspects of Cats library, mostly code snippets and I ’m not going to delve into any theory or mathematics.
Mostafa Asgari (@mostafaasg)
Why Scala Implicits

implicits aren’t just limited to functions, there’s implicit variables, classes, objects etc.
Gnanesh Kunal (@GnaneshKunal)
Implicits, type classes, and extension methods, part 4: understanding implicits

In previous posts, we covered most popular implicit use cases. What is left to complete the picture is the implicits mechanics itself.
Mateusz Kubuszok (@MateuszKubuszok)
Scala FUD FAQ for newbies

Is Scala dead? Is Scala hard? What are some real Scala issues? As well as many more questions answered!
Mateusz Kubuszok (@MateuszKubuszok)
Learning linear algebra with Scala

Some code examples in Scala, accompanying 3Blue1Brown’s “Essence of linear algebra” YouTube playlist.
Ruurtjan Pul (@Ruurtjan)
Cross-Platform Language Design

This is the thesis behind Scala.js, the dialect of Scala that compiles to JavaScript.
Sébastien Doeraene (@sjrdoeraene)
What’s New in IntelliJ IDEA

Improved display of implicit conversions and arguments, Missing and ambiguous implicit arguments hints, Improved autocompletion for type annotation and pattern matching, and Scalafmt as an alternative to the built-in formatter!
JetBrains (@jetbrains)
Enforcing rules at compile-time: an example

A story of a change in scalajs-react, which evolved into an interesting solution.
David Barri (@japgolly)


The Infamous Cake Pattern for Dependency Injection in Scala - Part 1

This is the 1/3 part of the video series in which we are going to learn about the infamous cake pattern, which is commonly discussed in the context of dependency injection. In order to explore the intricacies of this pattern we are going to write a massively over-engineered todo app with a terminal delivery mechanism and an in-memory persistence layer.
DevInsideYou (@DevInsideYou)


Lambda World Seattle, September 17th - 18th

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Scala Wave, September 6th - 8th, 2018, Gdańsk, Poland

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Scalac (@scalawavepl)
Scala Italy, September 14th-15th, Florence

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Scala Italy (@ScalaItaly)
LambdAle, London, September 1st

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LambdAle (@lambd_ale)
Win a ticket to Scala Italy!

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Signify Technology (@Signify_Tech)



A library of utilities for tagless final algebras.
cats-tagless contributors

A Scala port of the popular Python Requests HTTP client: flexible, intuitive, and straightforward to use.
Li Haoyi (@li_haoyi)

Typed Spreadsheet UI library for ScalaJS.
Jichao Ouyang (@oyanglulu)
json4s 3.6.0

A single AST to be used by other scala json libraries
json4s contributors


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