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September 24th, 2020, ISSUE 345


Tour of Scala

A set of interactive exercises so you can slowly build up knowledge about Scala.
Leo Benkel (@LeoBenkel)
Polynote, A better notebook for Scala

I will explain why I switched from Jupyter to Polynote for all my notebooks.
Vincent Brulé (@BruleVincent)
Single command Scala setup

Learn how to set up your development tools a simple command line utility.
Alexandre Archambault (@alxarchambault)
Dotty becomes Scala 3

This change will be part of the next Dotty release planned for October 1st which will be known as Scala 3.0.0-M1. We encourage maintainers of tooling (IDEs, build tools, ...) to prepare for this change now by special-casing the way they handle the compiler when its version number starts with 3.
Anatolii Kmetiuk (@AKmetyuk)
Functional Effects with ZIO

We reviewed some of the most popular options for functional programming on JVM and especially in the Scala ecosystem since it’s the most powerful language on JVM for functional programming. After that, we introduced ZIO and explained what functional effects are, by implementing a simplified version of ZIO.
Aleksandar Skrbic (@skrbic_a)
The Power of Akka Streams

In this article, a lot of Akka Streams capabilities are explained with a few examples, but it’s is just a tip of the iceberg.
Aleksandar Skrbic (@skrbic_a)


The Parallel typeclass in Cats

In this video, you'll learn about the Parallel typeclass: what problem it solves, how it's implemented in Cats, and how it can be used in your programs.
Jakub Kozłowski (@kubukoz)
Streaming with Monix

A presentation explaining in details how to understand Monix Observables.
Piotr Gawryś (@p_gawrys)
Tagless Final - Part 11 - main-http-http4s (The Big Rewrite)

In this video we will wire our upcoming http layer. We will use http4s to expose our routes.
DevInsideYou (@DevInsideYou)
Programming in Scala for beginners - week 2-4: programs, functions, objects

Open Scala lectures in Swedish by Björn Regnell at Lund University, Sweden.
Björn Regnell


Functional Scala CFP

The CFP closes on October 15th
Ziverge (@zivergetech)
Functional Design, October 20th - 22nd, Online training

In this course, developers will learn how to write simple functional solutions to everyday business problems, without jargon and without type classes. Use code "ScalaTimes10" to receive 10% off at the checkout.
John A. De Goes (@jdegoes)
The Rise of Loom and the Evolution of Reactive Programming, October 22nd, Online meetup

On Thursday, October 22nd at 8:00 PM (UK time) John A. De Goes will be giving a talk to the online meetup of ZIO London.
John A. De Goes (@jdegoes)
Scale By the Bay, November 12th - 14th, online event

Starting at 3:30 PM CET. Use promo code "FUNCTIONAL" to get a 10% discount for our readers!
Scale By The Bay (@ScaleByTheBay)
Functional Data Modeling, November 18th - 19th, Online training

In this course, developers will learn how to use functional Scala to construct simple, precise, and flexible models of any business domain. Use code "ScalaTimes10" to receive 10% off at the checkout.
John A. De Goes (@jdegoes)
ZIO Hackathon, November 20th-21st, online event

Attendees of ZIO Hackathon 2020 will be able to attend talks on ZIO projects from leading open source contributors, as well as receive expert mentorship in contributing features, bug fixes, and documentation enhancements to the ZIO ecosystem of libraries.
Ziverge (@zivergetech)
Functional Scala, December 3th-4th, London

Learn the critical topics you need to excel as a Scala developer, and celebrate the Scala programming language and community.
Ziverge (@zivergetech)
Scala 3 for Scala 2 developer, December 8th - 10th, Online training

In this course, developers who are already familiar with Scala 2.x will get a high-speed introduction to all the changes coming in Scala 3, including semantic changes, syntactic changes, new features, and dropped features. Use code "ScalaTimes10" to receive 10% off at the checkout.
John A. De Goes (@jdegoes)
Functional Scala Megapack (3 workshops)

Functional Design + Functional Data Modeling + Scala 3 for Scala 2 developers. Use our special link to get a 15% discount!
John A De Goes (@jdegoes)



ZIO circuit breaker, inspired by Polly, Resilience4J and Akka.
sbt 1.4.0-RC2

BSP buildTarget/run and buildTarget/test support, sbt-dependency-graph is brought into sbt, Updates to lm-coursier-shaded, retry with backoff during publish, and more. If no serious issues are found by Saturday, October 3rd 2020, 1.4.0-RC2 will become 1.4.0 final.
sbt contributors


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