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August 31st, 2023, ISSUE 496


Lightbend transfers ownership of sbt to the Scala Center

What does this mean for sbt users?
Scala Center (@scala_lang)

Covariance, Invariance and Contravariance (will refer to as CIC) in Scala determine the relationship between generic types and subtypin
Scala Algorithms
Type safety with Iron

A thorough comparison with the Refined library.
Michał Pawlik


Scala Days Madrid, Sept 11th-12th

Use our exclusive link for a 15% discount!
Scala Days (@scaladays)
Performance Optimization on the JVM, Sept 11th-15th, Online

In this 5-day workshop, the participants will learn about the two major runtime mechanisms of the JVM affecting performance - the JIT compiler and the garbage collector; techniques for writing performant JVM code and effective use of tools for analyzing performance.
John A. De Goes (@jdegoes)
London Scala Talks, Sept 20th

Monica McGuigan: "My First Year in Scala!", Jamie Willis: "Writing maintainable parsers with Parsley"
London Scala User Group (@londonscala)
10% discount for Learn Scala 3 Metaprogramming with John A. De Goes, Oct 23rd - 27th

In this course, developers will obtain a systematic and incremental introduction to building their own macros using Scala 3 metaprogramming. Covering trees and expressions, inlines and givens, quoting and splicing, and deriving, developers coming out of this course will be able to implement their own Scala 3 macros with confidence. Use our link for a 10% discount for Scala Times readers!
John A. De Goes (@jdegoes)
10% discount for Functional Scala, Nov 30th - Dec 1st, London

Use code ScalaTimesFS2023 and get our exclusive discount!
Ziverge (@zivergetech)
LambdaConf 2024, May 4th-10th, Estes Park, Colorado

Get ready!
LambdaConf (@lambda_conf)



http4s-stir offers Pekko HTTP-style (Akka HTTP-style) DSL directives for http4s using cats-effect's IO as an effect system.
circe 0.14.6

Some improvements and bugfixes.
circe contributors
Metals v1.0.1

Completions in Java files, liveness monitor, improvements for enums, semantic highlighting, and more!
Metals contributors

Fx Calculator is a typical calculator app for Android, but with two twists: 1. It has an advanced editor where you can write and use complex expressions. 2. It's written in Scala 3, JavaFX, and built with GraalVM Native Image. It's available on Google Play Store.
Maciej Gorywoda (@makingthematrix)

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