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February 25th, 2021, ISSUE 367

READING

The Coralogix Operator: A Tale of ZIO and Kubernetes

Discover zio-k8s and its capabilities.
Daniel Vigovszky (@dvigovszky)
Pure Functional Stream processing in Scala: Cats and Akka - Part 2

In this post, we find how to create Akka flows from pure functions in a syntactically cleaner way, with the help of some extension classes over Source and Flow. We also see how to construct more complex components and stitch them together using the GraphDSL.
Mihai Safta (@saftacatalin)
Introducing the lihaoyi-scala Github Organization

This is a short blog post to introduce the new com-lihaoyi Github organization: a place for all of my most production-ready projects will live to be easily maintained and discovered. We will discuss the status quo, what is changing, and what I hope to achieve with this change.
Li Haoyi (@li_haoyi)
Why Are Fibers Fast?

An excellent explanation why Cats Effect 3’s scheduler is able to achieve the crazy performance numbers we see in practice, and also why it is that fibers are not only an easier model for writing highly scalable modern applications, they are also a faster and more efficient model for running those applications at scale.
Daniel Spiewak (@djspiewak)
Implementing a CountDownLatch (async and dirty)

Yo dawg, I heard you liked concurrency primitives. Let’s implement our own asynchronous, dirty CountDownLatch.
Alexandru Nedelcu (@alexelcu)
Value Classes in Scala

One of the main rules of functional developers is that we should always trust a function’s signature. Hence, when we use functional programming, we prefer to define ad-hoc types to represent simple information such as an identifier, a description, or a currency. Ladies and gentlemen, please welcome the value classes.
Riccardo Cardin (@riccardo_cardin)

EVENTS

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)

RELEASES

Scala 2.13.5

TASTy reader: add support for Scala 3.0.0-RC1, allow name-based extractors to be irrefutable, better support for JVM 13+, and many more improvements.
Scala contributors
akka-persistence-postgres 0.5.0-M1

This release brings major change for journals partitioned by ordering values. (persistence_id, sequence_number) index is now unique and can be (re)built without taking any locks that prevent concurrent inserts, updates, or deletes on the table. In other words migration can be lockless.
akka-persistence-postgres contributors
Metals v0.10.0

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Sublime Text and Eclipse. New version brings type decorations for definitions, insert inferred type refactoring, configuration option for the default Scala version, improved short names when importing and many more updates!





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