A free, once-weekly Scala news flash. Easy to unsubscribe. Goes out every Thursday.
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!





  1. Scala Times Issue #389

    An intro to the Scala presentation compiler. From Scala 2 shapeless to Scala 3. IntelliJ Scala Plugin 2021.2. Scastie with Scala 3. Tooling Talks Episode 3 - Justin Kaeser.


  2. Scala Times Issue #388

    Data Times - Big Data and ML enthusiasts news flash. Story of importing a large dataset to Akka Cluster. Combining the terminal (iTerm) with the IDE. Metaprogramming in Scala 3: Inline. Part 6 - zio.Has - Getting Started with ZIO in Scala3.


  3. Scala Times Issue #387

    Will Scala 3 be your new favorite language?. Programming with Functions #8: Monads. Part 5 - ZIO.access - Getting Started with ZIO in Scala3. 12th ACM SIGPLAN Scala Symposium Call for Papers. ZIO Hackathon, Oct 29th - 31st (CET).


  4. Scala Times Issue #386

    Scala 3: Macros. 5 Key Lessons from Functional Programming in Scala. OAuth2 Scala application with sttp-oauth2, part 1 - Dev notes. Scala 3 Tech Report by SoftwareMill. Top Link of June: Scala 3 goodies for Scala 2 developers.


  5. Scala Times Issue #385

    Scala 3 Tech Report. ZIO: Introduction to Fibers. Problem: automatic coloring of effect monads in dotty-cps-async. Scala 3: Anti-Givens. (re)constructing sequences with Alternative.


  6. Scala Times Issue #384

    How to write a fire shader. Scala 3 goodies for Scala 2 developers. Composable Scala Matchers: Introduction. Writing an Interpreter From Scratch. Destroy your foldLeft with traverse and State - Scala tutorial.


  7. Scala Times Issue #383

    Existential Crisis: Implementing MapK in Scala 3 . What is ZIO and should you learn it?. Zymposium, June 18th (PDT). ZIO Hackathon, Oct 29th - 31st (CET). ScalaCon, November 2nd - 5th.


  8. Scala Times Issue #382

    Cats: Essential Type Class Hierarchy, Explained. Debugging and Observing Your Scala Code. Programs as Values, Part III: Explicit Control Flow. Programming in Scala Fifth Edition . Favor composition over inheritance in Scala3 with exports!.


  9. Scala Times Issue #381

    Top Level Exports in Scala3. Death of Blocker: blocking in Cats Effect 3 - Scala tutorial. Functional Scala, Dec 2nd - 3rd.


  10. Scala Times Issue #380

    Scala 3 Hello, world!. Scala 3 macros tips & tricks. Build your own refinement types in Scala 3. How To Implement Streaming Microservices Using ZIO and Kafka. How to successfully manage a ZIO Fiber’s lifecycle.


  11. Scala Times Issue #379

    Scala 3 is here!. New Online Course: Effective Programming in Scala. Image editing with Comonads. Generalized Algebraic Datatypes in Scala 3. Kind Projector Migration.


  12. Scala Times Special Scala 3 Issue

    Starting with Scala. Programming in Scala, Fifth Edition. Scala 3 Tech Report. Automatically Deriving Typeclass Instances in Scala 3. Starting with Scala 3 macros: a short tutorial.


  13. Scala Times Issue #378

    From Highschool to Teaching Scala. Rust for the Seasoned Scala Developer. Bring gRPC payloads and domain models closer with ScalaPB transformations. Flog: a functional logger for Scala. Opaque Type Alias in Scala 3.


  14. Scala Times Issue #377

    Typeclasses in Scala 3. Scala 3 Release Party - find out how it went!. Typelevel Discord migration. Scalabase, May 14th. ScalaCon, May 18th - 21st. and Nov. 2nd - 5th.


  15. Scala Times Issue #376

    Cats Effect 3 - Introduction to Fibers. Bintray to JFrog Artifactory migration status and sbt 1.5.1. Anomaly / outlier detection using isolation forest in Scala. Comparing Concurrent Programming Alternatives. Scala 3: Safer Pattern Matching with Matchable.


  16. Scala Times Issue #375

    A ZIO cheatsheet. Programming in Scala, Fifth Edition. Dealing with Optional Values. Best Features of Scala 3 for Scala.js. ZIO Meetup SF, April 22nd.


  17. Scala Times Issue #374

    Image editing with Monads. Fire-and-Forget in Cats Effect. Programming in Scala, Fifth Edition. Scala 3: Extension Methods. The Scala3 feature I'm most excited about!.


  18. Scala Times Issue #373

    Context is King. How to build an Android app in Scala 2.13. Revisiting Scala Native performance. Scala 3 in sbt 1.5. Programming in Scala, Fifth Edition.


  19. Scala Times Issue #372

    Using Cats Effect Resource in Non-Functional Contexts. Cats Effect · The pure asynchronous runtime for Scala. Figuring out Scala functional programming libraries. Scala 3: Infix Operator Notation. Building a transportation cloud with microservices.


  20. Scala Times Issue #371

    Introducing ZIO Http. Automatic UI generation with Scala 3's type class derivation. Scala is a Maintenance Nightmare. The Tagless Final Pattern in Scala. Scala3-migrate: a tool making it easier to migrate to Scala 3.


  21. Scala Times Issue #370

    The importance of Scala.js. Scala on Android. JDK 16's Top 5 for Scala. Many happy early returns. Zio quick read: Extracting the executor for a service.


  22. Scala Times Issue #369

    Tapir serverless: a proof of concept. Writing kubectl plugins with ZIO K8s. The future of Scaladoc. GSoC 2021 Here we come!. Programming in Scala Fifth Edition - New Release for Scala 3.


  23. Scala Times Issue #368

    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.


  24. Scala Times Issue #367

    The Coralogix Operator: A Tale of ZIO and Kubernetes. Introducing the lihaoyi-scala Github Organization. Why Are Fibers Fast?. Implementing a CountDownLatch (async and dirty). Value Classes in Scala.


  25. Scala Times Issue #366

    GraphQL Overview  -  Part2  -  Libraries. Scala's List has a Secret. Preventing Version Conflicts with versionScheme. Scala 3 Survey: The Conclusion. Upgrade your Tagless Final with Tofu.


Organizing an event?
Promote it with
Scala Times.
The Scala Times reader?
Get a banner!
Got a tip?Send it in!
Follow us onTwitter.
Curated bySoftwareMill.
We arehiring.
Andtaking on projects.