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March 19th, 2021, ISSUE 370


The importance of Scala.js

Why would a frontend developer take on Scala.js when they probably already have 5 browser tabs open for HTML5 APIs, JavaScript APIs, WebPack documentation, TypeScript guides and the application itself they are developing on?
William Narmontas (@ScalaWilliam)
Scala on Android

Learn about how to develop Scala apps using different stacks, even GraalVM!
Maciej Gorywoda (@makingthematrix)
JDK 16's Top 5 for Scala

Here are my top 5 improvements of the JDK 16, from the Scala perspective.
William Narmontas (@ScalaWilliam)
Many happy early returns

I decided to write this article because I remember that back when I started to learn Scala around 2013-2014 the problem of how to return early from a loop actually happened to me a few times.
Maciej Gorywoda (@makingthematrix)
Zio quick read: Extracting the executor for a service

Let’s say you have the need to obtain an Executor from the default zio runtime and use it to create a service. Let’s assume you have a simple function to make your service. This function has no zio knowledge.
Using ZIO Kafka with offset storage in Postgres for transactional processing

A detailed example about how to use ZIO Kafka, Skunk, Cats, and Postgres to address a typical use case.
Marek Kadek (@MarekKadek)
Programming in Scala Fifth Edition - New Release for Scala 3

PrePrint PDF update of Programming in Scala is now available. Use code SCALATIMESMARPINS5 for 15% off. Offer expires 3/31/2021.
Artima, Inc. (@ArtimaInc)
Top Link of February: Functional Design

This great article received a lot of attention last month, so let's highlight it!
Francis Toth (@francistoth)


Generate case classes from some JSON in 25 seconds

In this video we are going to learn about an awesome website https://json2caseclass.cleverapps.io/ which given a JSON sample generates Scala case classes for you that you can copy paste into your project.
DevInsideYou (@DevInsideYou)
THE most important programming concept explained in 35 seconds.

In this video we are going to learn about the 2 kinds of polymorphism: parametric and ad-hoc.
DevInsideYou (@DevInsideYou)
What is a Monad? In 60 seconds!

In this video we are going to learn about what a Monad is!
DevInsideYou (@DevInsideYou)
N-Queens in Scala: Approaching an Interview Problem With Pure Functional Programming

This episode is a bit different. This time, I'm going to show you one of the problems I solve with my students in the Scala & FP Interview Practice course.
Daniel Ciocîrlan (@rockthejvm)
Semigroups and Monoids in Scala

In this video we'll look at Semigroups and Monoids, two abstractions for functional programming derived from abstract algebra. We'll see how they would look like in Scala, and then we'll see what kind of practical problem they solve (besides adding more abstract math to programming).
Daniel Ciocîrlan (@rockthejvm)
Programming with Functions #5 - Immutability

How do you think, where is the border? Where do you decide that enough is enough and reach for ArrayBuffer?
Maciej Gorywoda (@makingthematrix)
Pick any Card: Write Better Data Structures with Scala | Let's talk about Scala 3

In the second video in the "Let's talk about Scala 3" series, Jamie Thompson, a Compiler Engineer at the Scala Center, walks us through writing better data structures with Scala using a game of cards as an example.
Jamie Thompson (@bishabosha)


Production-grade microservices with ZIO, March 24th, online event (GMT)

In this talk, Itamar will share from his experience in running microservices-based on ZIO in production: resilient, Kubernetes-friendly structuring; cloud-native observability with logs, metrics and telemetry, and modern ways of service communication.
Itamar Ravid (@itrvd)
Scala 3 Release Party, April 24th

Be there for the final countdown! A virtual event with free registration. Starts 6:00 PM.
sphere.it (@sphere_it_)
Practical Functional Programming with Typescript workshop, May 5th - 7th

20% off for Scala Times readers!
Matechs, Ziverge
ScalaCon, May 18th - 21st. and Nov. 2nd - 5th, online event

Brought to you by ScalaDays and Scala eXchange, ScalaCon is a series of virtual conferences designed to bring the Scala community closer together.
ScalaCon (@scalacon)



Scala cfor macro, like a java for-loop.
Roman Grebennikov

Declarative concurrency and stream processing library for Scala.
Tomas Mikula (@tomas_mikula)

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