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December 24th, 2020, ISSUE 358


VirtusLab’s Scala 3 cooperation update

When Martin Odersky joined the VirtusLab Advisory Board, we promised to publish the summary of our involvement in the Scala 3 ecosystem. Here it is!
VirtusLab (@VirtusLab)
Scala 3.0.0-M3: developer's preview before RC1

It is intended to contain all the features meant for RC1, which is tentatively planned for January 2021. The purpose of M3 is to give the larger community, beyond early adopters, a chance to try out all the features and give us feedback before sealing them in RC1.
Anatolii Kmetiuk (@AKmetyuk)
How to Use Thread.sleep Without Blocking on the JVM

How to leverage new JVM features or ZIO to avoid blocking sleeping.
Daniel Sebban (@dsebban)
New in Scala 3

Here we provide you with a quick overview of the most important changes.
Scala Center (@scala_lang)



Technical talks from the best San Francisco Bay Area meetups for software engineers and data scientists devoted to thoughtful and scalable programming and AI. All By the Bay conferences, as well as speaker interviews, are published here for free shortly after the events.


Scala Love CFP

Scala Love takes place on February 13th, from 9:00 AM to 11:00 PM Central European Time (12:00 AM Midnight to 2:00 PM Pacific Standart Time). We are going to have two tracks: one for speakers based in Europe/Asia and one for speakers based in America! CFP closes at January 10, 2021 23:59 UTC January 11, 2021 00:59 CEST (Local)
Scala Love (@scala_love)
Lambda Days 2021, 16th - 19th February, Virtual Event

Grab the early birds tickets before Jan 14th! Don't forget to check the Diversity Scheme - we have a pool of tickets to be distributed among participants from groups underrepresented in IT.
LambdaDays (@LambdaDays)



This library aims to provide easy integration with OAuth2 providers based on OAuth2 RFC using sttp client. It uses circe for JSON serialization/deserialization.
sttp2-oauth contributors
cats-effect v3.0.0-M5

We are expecting to follow this milestone with subsequent ones as necessary to further refine functionality and features, prior to some number of release candidates leading to a final release. The designation "M5" is meant to indicate our relative confidence in the functionality and API of the library, but it by no means indicates completeness or final compatibility. Neither binary compatibility nor source compatibility with anything are assured prior to 3.0.0, though major breakage is unlikely at this point.
Cats Effect contributors

  1. 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?.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

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    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!.

  8. 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?.

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  10. Scala Times Issue #352

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  11. Scala Times Issue #351

    Autorecovery for (JMS) Streams. ZIO-AWS with ZIO Query. Implementing Scala.js Support for Scala 3. Let’s Talk About the Scala 3 Indentation. Concurrency in Cats Effect 3.

  12. Scala Times Issue #350

    Designing tapir’s WebSockets support. BSP Support in sbt 1.4. Streaming With Probabilistic Data Structures: Why & How. Scala 3 Migration guide. ScalaZONE - Scala 3 Programming Language Courses.

  13. Scala Times Issue #349

    Generic IOApp alternative. Let's build a Scala mock library. How To Make Integration Tests Less Flaky. Option  - the null of our times. Top Link of September: Polynote, A better notebook for Scala.

  14. Scala Times Issue #348

    Java 15 through the eyes of a Scala programmer. Functional Design, October 20th - 22nd, Online training. Scale By the Bay, November 12th - 14th, online event. Functional Data Modeling, November 18th - 19th, Online training. ZIO Hackathon, November 20th-21st, online event.

  15. Scala Times Issue #347

    A short guide to Blocker. Using: Did they forget something?. The assignment operator is broken!. Attending a hackathon with Scala and Akka (Streams) on Microsoft Azure. Programming Scala, Third Edition.

  16. Scala Times Issue #346

    Getting Started with Knative in Scala. Tagless Final - Part 12 - delivery-http-http4s (The Big Rewrite). Programming in Scala for beginners - week 5: classes. Eyjafjallajökull Lecture 2019. Scala 3: Enums.

  17. Scala Times Issue #345

    Tour of Scala. Polynote, A better notebook for Scala. Single command Scala setup. Dotty becomes Scala 3. Functional Effects with ZIO.

  18. Scala Times Issue #344

    Can we build better?. Algebra and Parametricity. How to Deploy a Scala Application to AWS Lambda. 5 lessons learned from my continuing awesome journey with ZIO. Scala 3 - A community powered release.

  19. Scala Times Issue #343

    Underscores are Overloaded in Scala!. Scala, React, and SSR (part 2). Scala Africa Development Program Has Launched. Scala micro.sphere.it, September 15th. Essential Effects EU, September 14th-16th, Online Course.

  20. Scala Times Issue #342

    What’s coming up in sttp client 3?. FP in the City Virtual Conference, September 10th. Scala Castle, September 14th-17th. Scala micro.sphere.it, September 15th. Essential Effects EU, September 14th-16th, Online Course.

  21. Scala Times Issue #341

    Concurrency In Scala with Cats-Effect. Scala, React, and SSR (part 1). More Algebra of Algebraic Data Types. Akka HTTP 10.2 Release - Q/A with the Akka team. Type-Level Programming in Scala, Part 3.

  22. Scala Times Issue #340

    SoftwareMilling around OSS - Scala Love. More Intuition on Optics. Type-Level Programming in Scala, Part 2. An Introduction to Functional Design. VimtelliJ: All the best of Vim in IntelliJ.

  23. Scala Times Issue #339

    Scala Knowledge Bits Archives. Functional Effects with ZIO. Experiment with Loom. Auto publish sbt plugin from Travis CI. Scala String Interpolation.

  24. Scala Times Issue #338

    ZIO 1.0 Released. Retry Failing Tasks with Cats and Scala. An Intuition for Optics. Evoneering - Scala Bootcamp. How Does "20 seconds" Work in Scala?.

  25. Scala Times Issue #337

    Thinking With Types. IntelliJ Scala Plugin 2020.2 is released!. Announcing Dotty 0.26.0-RC1. A Dive into Configuring Metals · Metals. Life with fatal warnings.

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