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November 19th, 2020, ISSUE 353

READING

Functional pancakes

Let’s apply functional programming to a practical problem. Can you guess what it’s going to be?
Adam Warski (@adamwarski)
Scala 3 Developers Survey

The survey is for all developers, whether you’re a professional, a hobbyist, or a student who code in Scala. Share your experience and expectations, and win an Amazon Gift card!
SoftwareMill (@softwaremill)
Managing Database Migrations in Scala

A very popular Java library for handling migrations is Flyway. We’ll combine that with Typesafe Config (aka HOCON) for configuration, along with PureConfig for parsing it. And Cats Effect for describing our effects, because we love FP, right?
Alex Nedelcu (@alexelcu)
One year with Akka 2.6

If you haven’t followed all announcements in detail, this post gives an overview of what has happened during the last year.
Akka Team (@akkateam)
Best practice for natural Ordering

Scala has scala.math.Ordering, Java has java.lang.Comparable. These are interfaces used for defining a natural order, which can then be used to sort lists of elements, or in data structures implemented via binary search trees, such as SortedSet.
Alex Nedelcu (@alexelcu)
Event-driven railway network based on Pulsar

An introduction to Apache Pulsar and Neutron (a Pulsar client based on fs2).
Pavels Sisojevs (@scalamonster)
Mirror, Mirror on the Wall, Who’s the Genericioust of Them All?

Discover generic programming with Scala 3.
Philipp Martini (@maphiFP)

VIDEOS

Tagless Final - Part 15.2 - trust, but verify (The Big Rewrite)

In this video we will write tests and conclude the series. This is part 2/2.
DevInsideYou (@DevInsideYou)
Programming in Scala for beginners - week 9: sets and key-value tables

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

Here's the first episode in a series of collaborations with excellent developers and speakers from the Scala community.
Jakub Kozłowski, Wiem Zine (@WiemZin)
Given and Using Clauses in Scala 3

This video will continue the Scala 3 journey. This one is pretty important as it covers the new "contextual abstractions": given instances and using clauses.
Daniel Ciocîrlan (@rockthejvm)

EVENTS

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)
London Scala Open Source Saturday, November 28th, online event

Come and meet up with fellow contributors and maintainers to hack on their projects. We'll tackle good first issues in Scala, ScalaJS, and many more! First time contributors are especially welcome to help improve the https://www.lsug.co.uk/ website, written in functional Scala. Whether you're an experienced contributor or new to GitHub, we'll help you get your first taste of an open source project.
London Scala User Group (@londonscala)
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

sbt 1.4.3

Featuring update to Coursier 2.0.6, IntelliJ import fix on Windows, metabuild dependency resolution fix, and more.
sbt contributors
Akka HTTP 10.1.13

This is a small maintenance release which fixes a bug in the client connection pool and optimizes some cases of discarding entities.
Akka Team (@akkateam)





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