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April 29th, 2021, ISSUE 376


Cats Effect 3 - Introduction to Fibers

Learn all about the fundamental concept that powers your effects.
Daniel Ciocîrlan (@rockthejvm)
Bintray to JFrog Artifactory migration status and sbt 1.5.1

There's now a cloud-hosted Artifactory instance licensed to Scala Center, and fully sponsored by JFrog. Let's call this "Artsy" in this post instead of the Artifactory instance. With the release of sbt 1.5.1, I think we can say that the migration is done.
Eugene Yokota (@eed3si9n)
Anomaly / outlier detection using isolation forest in Scala

This article is describing the journey of implementing the unsupervised learning algorithm isolation forest for anomaly / outlier detection from scratch.
Kristof Slechten (@KristofSl)
Comparing Concurrent Programming Alternatives

This article is a rewrite of a blogpost about calculating π concurrently using Scala’s Future and that was published in 2014. Two major changes that are introduced are: discuss alternative implementations based on Akka Streams, and use Scala 3 instead of Scala 2 and utilise the existing Akka 2.6.14 library that was compiled with Scala 2 in a transparant fashion.
Eric Loots (@lootser)

I put together a miniature ~270 line implementation of Dotty-Quill that is a good reference for learning and benchmarking (based on my work with the ScQuilL group). Feel free to have a look.
Alexander Ioffe (@deusaquilus)
Scala 3: Safer Pattern Matching with Matchable

Late in the Scala 3 development process, a new type scala.Matchable was introduced to fix a loophole in pattern matching. This post discusses that loophole, how Matchable fixes it, and implications of this change.
Dean Wampler (@deanwampler)
TASTY way of (re)writing macros in Scala 3

The aim of this blog post is to serve as a manual on efficiently using and navigating through Quotes API (which is the core of metaprogramming), rather than being a migration guide for macros or Scala projects in general.
Kacper Korban (@KacperKorban)
Programming in Scala, Fifth Edition

PrePrint PDF update of Programming in Scala is now available. Use code SCALATIMESAPRILPINS5 for 15% off. Offer expires 4/30/2021.
Artima, Inc. (@ArtimaInc)
Top Link of March: Scala is a Maintenance Nightmare

Before we switch to the next month, let's take a look at the previous month, and its shiniest higlight!
Matthew Powers (@neapowers)


Cats Effect 3: Racing IOs (and Fibers)

How to race two IOs and get the result of the winner, how to listen for a fiber cancellation, how to implement the timeout pattern, and how to race two IOs without cancellation with racePair.
Daniel Ciocîrlan (@rockthejvm)
Scala Crash Course by a Scala veteran (with some JavaScript flavor)

Learn Scala in one video from a 10+ years Scala veteran.
DevInsideYou (@DevInsideYou)


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

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)
Functional Scala, Dec 2nd

Functional Scala 2021 returns for another year of great talks, familiar and fresh spaces, and positive energy around the power of functional Scala for delivering compelling solutions to the toughest technology problems. Use promo code SCALATIMES10 for a discount for our readers!
Functional Scala (@FunScala2021)


quicklens 1.7.0

Now with Scala 3 support!
quicklens contributors

  1. 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.

  2. 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.

  3. 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.

  4. 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!.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Scala Times Issue #365

    Coding Adventures with Party Parrot Game . Scala Cats Contravariant Functors. From First Principles: Why Scala?. Idiomatic Error Handling in Scala. Stop Letting Your Tests “Make” Your Luck.

  14. Scala Times Issue #364

    Why we need yet another Akka Persistence plugin?. Match Types in Scala 3. A Metals Retrospective (Part 1) · Metals. Making the Spark DataFrame composition type safe(r). Type driven API development using Scala and Tapir.

  15. Scala Times Issue #363

    How to Sort Lists in Scala with Tail Recursion. Image editing with Functors. Tail Recursive Functions (in Scala). Algebraic Data Types (ADT) in Scala. Ep 6: Functional error handling with applicative in Scala 3.

  16. Scala Times Issue #362

    5 Blogs for Scala's Birthday. Monocle 3 Roadmap. Higher-kinded data in Scala. Objects and Companions in Scala. Essential Effects, 27th-29th January, Online Event.

  17. Scala Times Issue #361

    Scala 3: Dependent Types, Part II. Configuring and suppressing warnings in Scala. Threading best practices in Cats Effect. Scala 3 Metaprogramming by Example by Adam Warski. What the Functor?.

  18. Scala Times Issue #360

    Scala 3: Dependent Types, Part I. Publish Scala 2 and Scala 3 macros together. Concurrent state machines. Wire Signals - Yet Another Event Streams Library. Scala Love CFP.

  19. Scala Times Issue #359

    Implementing Type classes in Scala 3. Finite-State Machines + FS2 streams: A match made in heaven. Scala Compiler Options, Fatal Warnings and Linting Guide. ZLayers by example. Scala 3 type classes.

  20. Scala Times Issue #358

    VirtusLab’s Scala 3 cooperation update. Scala 3.0.0-M3: developer's preview before RC1. How to Use Thread.sleep Without Blocking on the JVM. New in Scala 3. Scala Love CFP.

  21. Scala Times Issue #357

    Join the Scala Discord Server!. Enforcing Semantic Versioning with sbt-strict-update. Kafka Cron using wix/greyhound. Scala Filesystem Operations (paths, move, copy, list, delete) . Metals 2020 Review.

  22. Scala Times Issue #356

    Scala 3 Developers' Survey. Tapir vs Endpoints4s. Opaque Type Aliases and Open Classes. Akka Platform Guide. Type classes with Scala 2.

  23. Scala Times Issue #355

    Scala 3 Developers' Survey. Four new features of Scala 2.13 releases that you probably missed. Scala 3: Path-Dependent Types, Dependent Methods and Functions. Message-based Parallelism with Actors. IntelliJ Scala Plugin 2020.3 Is Out!.

  24. Scala Times Issue #354

    Scala 3 Developers Survey. A case for akka-coordination lease. Monad transformers and cats  -  3 tips for beginners. Forward Compatibility for the Scala 3 Transition. Mirror, Mirror on the Wall, Who’s the Genericioust of Them All?.

  25. Scala Times Issue #353

    Scala 3 Developers Survey. Managing Database Migrations in Scala. One year with Akka 2.6. Best practice for natural Ordering. Event-driven railway network based on Pulsar.

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