A free, once-weekly Scala news flash. Easy to unsubscribe. Goes out every Thursday.
April 25th, 2019, ISSUE 271

READING

ZIO & Cats Effect: A Match Made in Heaven

ZIO is awesome for many reasons: Better MTL / Tagless-Final, Resource-Safety for Mortals, Guaranteed Finalizers, Stable Shifting, Lossless Errors, Deadlock-Free Async, Precise Future Interop, Blocking IO, Cost-Free Effects, and more!
John A De Goes (@jdegoes)
Concurrency is complicated

There are many other concurrency challenges that we can face, but it’s important to understand the reasons and the causes.
Wiem Zine (@WiemZin)
An introduction to Law Testing in Scala

Law testing allows you to reason about your data-types and functions in a mathematical and concise way and provides a totally new paradigm for testing your code!
Dor Sever
Celebrating 10 Years of Akka

Check out this 10-Year Akkaversary Magazine—a commemorative guide of white papers, blog posts, and articles that have shaped the Akka journey.
Lightbend (@lightbend)
Alphabet Soup: Type-level transformations

Reducing boilerplate is always fun, learn how you can automatically convert between similar types without writing tedious field-to-field converters.
James Phillips

PRESENTATIONS

Crash Course - Property Based Testing with ScalaCheck

In this video we will learn about property based testing, which is an alternative to example based testing.
DevInsideYou (@DevInsideYou)

EVENTS

ScaLATAM, Montevideo, Uruguay, May 2nd - 3rd

Don't miss the first Scala Conference in Latin America. Use promo code "scalatimes" to get 25% discount for our readers!
ScaLATAM
flatMap(Oslo), Oslo, Norway, May 8th - 9th

Use promo code SCALATIMES for a discount for our readers!
flatMap(Oslo) (@flatmaposlo)
Reactive Horizons, Orlando, Florida, May 31st

This conference is a unique opportunity to learn about top trending topics from today's Fast Data experts!
Reactive Horizons
CFP for LX Scala & Reactive, Lisbon, Portugal, July 4th - 5th

Don't miss the CFP deadline which is May 1st!
LX Scala & Reactive (@LX_Scala)
CFP for Lambda World, Cádiz, Spain, October 17th - 18th

Deadline for submissions is June 1st.
Lambda World (@lambda_world)
CFP for Scala Italy, Bologna, Italy, September 20th - 21st

Submit your proposal before May 5th.
Scala Italy (@ScalaItaly)

PODCAST

Scala Love Episode 47 with Raúl Raja Martínez

Enjoy this conversation with CTO & Co-Founder at 47 Degrees.
Scala Love (@scala_love)

RELEASES

http4s v0.20.0

Typeful, functional, streaming HTTP for Scala... Version 0.20 brings Scala 2.13 compatibility, EOL of 0.18, some breaking changes, enhancements (mediaType String context macro for validating literals) and bugfixes.
http4s contributors
Scala Native 0.3.9

An impressive set of improvements and fixes.
Scala Native contributors
Mu v0.18.0

Mu is a purely functional library for building RPC endpoint based services with support for RPC and HTTP/2.
Mu contributors
Cats 2.0.0-M1

A milestone release, maintains binary compatibility on cats-kernel, cats-core and cats-free with Cats 1.x.x.
Cats contributors
Akka Persistence Couchbase

The Akka Persistence Couchbase plugin allows for using Couchbase 5.1 and newer as a backend for Akka Persistence and Akka Persistence Query.
Akka Persistence Couchbase contributors

VARIA

Scala Times banners?

Want one? Click here
THE INTERNET
Scala Times stickers?

Want one? Let us know or tweet @scalatimes.
THE INTERNET





  1. Scala Times Issue #283

    Python vs. Scala: a comparison of the basic commands. Keep your projects up-to-date with Scala Steward. My favorite new features of Scala 2.13 standard library. Implementing a server for the Language Server Protocol. Homegrown Scala Collections: Testing Streams.


  2. Scala Times Issue #282

    Read Pure functional HTTP APIs in Scala | Leanpub. Combining ZIO and Akka to enable distributed FP in Scala. Rethinking Streaming Workloads with Akka Streams: Part II. ES/CQRS the Akka way - Krunoslav Uzelac - Medium. Tour of Akka Typed: Protocols and Behaviors.


  3. Scala Times Issue #281

    Abstracting Over Effect Types. Reusable pre-commit hooks in Scala projects. Functional Highlighting for Functional Programming. Top Link of June: The Evolution of a Scala Programmer. Lambda World, Cádiz, Spain, October 17th - 18th.


  4. Scala Times Issue #280

    Comonads for Life. TypeSafe journey using Scala. Scala programming language wins SIGPLAN award. Shapeless' HLists and how to traverse them. How to work with JSON in Scala.


  5. Scala Times Issue #279

    Thread shifting in cats-effect and ZIO. How to work with HTTP JSON APIs in Scala. ZIO with http4s and doobie. Optimizing CI build times for Scala projects. The False Hope of Tagless-Final in Scala.


  6. Scala Times Issue #278

    Counting to infinity at compile time. Vectos - A functional ecosystem. Scala 2.13.0 for the Akka family. The place of applicative style in today's Scala. This Month We've Learned - May’19 .


  7. Scala Times Issue #277

    Final Free Structures with Subtyping. Exploring the STM functionality in ZIO. The Evolution of a Scala Programmer. How to work with Files in Scala. Top Link Of May: The little gems of Scala standard library.


  8. Scala Times Issue #276

    Small & fast Docker images using GraalVM’s native-image. SystemFw FP blog. IO monad: which, why and how. Counting at compile time. Why I'm Stepping Back from Scalaz.


  9. Scala Times Issue #275

    Tagless unions in scala 2.12. Combine IntelliJ IDEA with Hydra for the fastest Scala development experience. TMWL April’19  - qubits, scripting Google Apps & Scala tricks. Performant Functional Programming to the max with ZIO.


  10. Scala Times Issue #274

    AST playground: recursion schemes and recursive data. Rethinking Streaming Workloads with Akka Streams: Part I. Sharing is Caring!. A Scala tutorial for Java developers. Scala: Useful User Information + Why you should consider the Language.


  11. Scala Times Issue #273

    Community and Communication. Futures Made Easy with Scala. Scala: Useful User Information + Why you should consider the Language. Using 47 Degree's Fetch library with ZIO. Scala Compilation Got 5x Faster With Triplequote Hydra.


  12. Scala Times Issue #272

    The little gems of Scala standard library. Practical fiber safety (and how Concurrent implies Parallel). Typelevel Sustainability Program Announcement. Homegrown #Scala Collections - ScalaCheck / ScalaTest Integration. Alphabet Soup: Lensing, for free.


  13. Scala Times Issue #271

    ZIO & Cats Effect: A Match Made in Heaven. Concurrency is complicated. An introduction to Law Testing in Scala. Celebrating 10 Years of Akka. Alphabet Soup: Type-level transformations.


  14. Scala Times Issue #270

    Akka 2.6 roadmap. Extending MapR Database Queries Using Scala Polymorphic Types. Marvels of functional programming: Composing effects with monads. Traverse your HLists for fun and profit. Did Functional Programming get it wrong?.


  15. Scala Times Issue #269

    Scalar 2019 whiteboard voting. 38 lines of code towards better data validation in Scala. Scala: Internals and Intermediates. Hacker News API Part 5. Scala Ordering Crash Course.


  16. Scala Times Issue #268

    Functional Hangman with ZIO. Scala or Go: Tastes Great or Less Filling?. An Example of Free Monads and Optimization. Homegrown Scala Collections - Part 29 - Are Views Typeclasses?. Scalar, Warsaw, Poland April 5th - 6th.


  17. Scala Times Issue #267

    Bloop’s compiler performance is ~29% faster than SBT. Fourth batch of Scala 3 SIPs. Functional Hangman with ZIO. Scala: Understanding Variance. Fun with mutually-recursive typeclass resolution.


  18. Scala Times Issue #266

    The RedMonk Programming Language Rankings: January 2019. A monad is not a burrito. Joins in Apache Spark - Part 3. Scala sbt Project Directory Structure. Scala Snippets #1: Instantiable Implicits.


  19. Scala Times Issue #265

    Testing Incrementally with ZIO Environment. Finally Tagless - Not Quite Dead Yet. Functional Testing with Tagless-Final. Monad Transformers aren’t hard!. The Functional Scala Concurrency Challenge.


  20. Scala Times Issue #264

    Final Tagless seen alive. Effectful Episode with John de Goes. State vs Stateful Actor. Phil Bagwell Nominations. Introduction to Akka Streams.


  21. Scala Times Issue #263

    Describe, then interpret: HTTP endpoints using tapir. Vue.js with Playframework. Mu-RPC: defining messages and services. Validate Service Configuration in Scala. Modern Systems Programming And Scala Native With Richard Whaling.


  22. Scala Times Issue #262

    Is your Scala object always a singleton?. Freer doesn’t come for free. Maintaining Binary Compatibility in Scala. Anatomy of functors and category theory. A little Scala 'sed' class.


  23. Scala Times Issue #261: from Scala with love

    Aecor — Purely functional event sourcing in Scala. Part 5. Homegrown #Scala Collections - Foldable Maps. Kubernetes Liveness and Readiness Probes Revisited. Streams and Resource Safety | Akka. Assemble messages from Akka Actors.


  24. Scala Times Issue #260

    Cats Ecosystem Community Survey 2018 Results. Thread Pool Best Practices with ZIO. Purely functional parallelism in Scala. Finatra meets Ammonite. Typed Supervision: why the changes?.


  25. Scala Times Issue #259

    State of Scala compilation time in 2018. Low-memory symbol indexing with bloom filters. Finally: Top-level Definitions. Why you should think about functional programming. Toward a polyglot James server….


Organizing an event?
Promote it with
Scala Times.
The Scala Times reader?
Get a banner!
Got a tip? Send it in!
Follow us on Twitter.
Curated by SoftwareMill.
We are hiring.
And taking on projects.