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March 4th, 2021, ISSUE 368


Scala 3 Tech Report

The report summarises developers' expectations for Scala 3 and their view on the future of Scala.
SoftwareMill (@softwaremill)
Tuples bring generic programming to Scala 3

In Scala 3, tuples gain power thanks to new operations, additional type safety and fewer restrictions, pointing in the direction of a construct called Heterogeneous Lists (HLists), one of the core data structures in generic programming.
Vincenzo Bazzucchi
Scala Cats Invariant Functor

If you understand the concept of Covariant and Contravariant types of functors, then the Invariant will be easy to grasp as it combines functionality from both the functors mentioned above.
Krzysztof Grajek (@grajo)
Lean for Scala programmers

Lean is a theorem prover and programming language It is based on the calculus of constructions with inductive types.
Juan Pablo Romero Méndez
Scala Algorithms

An e-resource offering a variety of thoroughly explained algorithms, with free samples.
William Narmontas (@ScalaWilliam)


Structuring Services with ZIO and ZLayer

We learn to structure our various services so that they're more modular and independent, consistent in their structure, easier to read and maintain, and easy to combine.
Daniel Ciocîrlan (@rockthejvm)


SF Scala: How to survive algorithms in Scala & A Metals Retrospective, March 6th

In the first talk, you will learn about William's journey with algorithms in Scala and the educational website "Scala Algorithms". Then Chris will give an overview of the newest Metals features and large changes that happened this past year, giving a preview of what is likely to come this year, and also spend some time addressing common misconceptions that users may have about Metals and the Metals ecosystem.
William Narmontas, Chris Kipp
ZIO World, March 11th, online event

Join ZIO users and contributors for the inaugural ZIO World, which reveals ZIO 2.0, providing inspiration and new opportunities to create the most powerful reactive applications on the JVM. FREE of charge for all ZIO Contributors and Users.
Ziverge (@zivergetech)
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)
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)


http4s 0.22.0-M5

Introducing support for Scala 3, new header model, some removed deprecations, and more!
http4s contributors
sttp 3.1.7

Web sockets support in JS backend, as well as many dependency updates.
sttp contributors

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    Scala 3 Tech Report. Tuples bring generic programming to Scala 3. Scala Cats Invariant Functor. Lean for Scala programmers. Structuring Services with ZIO and ZLayer.

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