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November 12th, 2020, ISSUE 352

READING

Domain-Driven Design with FP in Scala

We saw what DDD means in the context of backend Scala applications. With DDD mindset, we try to keep the domain model as close as possible to reality, knowing it’s the only touchpoint between the code and fuzzy real world. Scala, in contrast to other programming languages, definitely helps us with that.
Bartłomiej Szwej (@bszwej)
Explicit term inference with Scala 3

One of the most striking changes for developers adopting Scala 3 is the introduction of a new syntax to replace the implicit mechanism used in previous Scala versions.
Meriam Lachkar, Vincenzo Bazzucchi
Keep alive for JMS connections

The keep alive build on the streams with auto recovery and triggers a reconnect once a limit of maximum missed keep alives has been reached. The reconnect then triggers the recovery and reconnect as defined for auto recovery.
Andreas Gies
Why You Should Learn Scala in 2020?

Is Scala the perfect language for your needs? Find out!
Marcin Krykowski (@marcinkrykowski)
A step-by-step guide for debugging memory leaks in Spark Applications

Memory leaks can happen, but there is a number of things you can do to investigate them.
Shivansh Srivastava
I like Option.get

I’ll blame Scala and Haskell, and not the availability of Option.get. I learned to expect more from my tools. It’s not me, it’s you, Scala.
Alexandru Nedelcu (@alexelcu)
Top Link of October: Java 15 through the eyes of a Scala programmer

The most interesting article from the previous month. Let’s take a look at how the (preview or final) features available in Java 15 relate to constructs known in Scala.
Adam Warski (@adamwarski)

VIDEOS

Programming in Scala for beginners - week 8: matrices, type parameters

Open Scala lectures in Swedish by Björn Regnell at Lund University, Sweden.
Björn Regnell
Working with JSON in Scala, a Circe Crash Course

If you're new to the language, or simply think JSON handling is confusing, consider taking a look!
Guillaume Bogard (@bogardguillaume)
Variance Positions in Scala, Demystified

This video is for the mature Scala developer. We talk about variance in Scala as an innocent question: if A extends B, should Thing[A] be a subtype of Thing[B]?
Daniel Ciocîrlan (@rockthejvm)

EVENTS

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)
Essential Effects (US), November 18th-20th, online event

sential Effects teaches how to safely create, compose, and execute effectful Scala programs using the Typelevel cats-effect library, and how to integrate these concepts and techniques into your projects. The course will take place online as three 4-hour sessions with breaks, 9am-1pm PST (UTC-7). Use discount code 'scalatimes' for a discount!
Inner Product (@InnerProductLLC)
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. Every Contributor to the ZIO library during the ZIO Hackathon will receive this collectible T-shirt!
Ziverge (@zivergetech)
Essential Effects (EU), November 23rd-25th, online event

Essential Effects teaches how to safely create, compose, and execute effectful Scala programs using the Typelevel cats-effect library, and how to integrate these concepts and techniques into your projects. The course will take place online as three 4-hour sessions with breaks, 12pm-4pm UTC.
Inner Product (@InnerProductLLC)
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. Every ticket holder to Functional Scala 2020 will receive an all-day Scala 3 course by John de Goes and a collectible T-shirt!
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)

RELEASES

contextual 2.0

Statically-checked string interpolation.
Jon Pretty (@propensive)
Monix 3.3.0

Better Stack Traces, Better Task => Future interop when using Local, and many more updates!
Monix contributors
scala-steward 0.8.1

Scala Steward is a bot that helps you keeping library dependencies and sbt plugins up-to-date.
scala-steward contributors
sbt-explicit-dependencies

An sbt plugin to check that your libraryDependencies accurately reflects the libraries that your code depends on in order to compile.
sbt-explicit-dependencies contributors
cats-parse

A parsing library for the cats ecosystem
cats-parse contributors





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