A free, once-weekly Scala news flash. Easy to unsubscribe. Goes out every Thursday.
June 27th, 2019, ISSUE 280

READING

Comonads for Life

We will look at Comonads, a type class closely related to Monads, firstly from an abstract point of view and progressing to a couple of practical, yet simple, examples of using Comonads for interesting applications.
Justin Heyes-Jones (@justinhj)
TypeSafe journey using Scala

A quick book on Scala Type System.
Harmeet Singh (@singh_harmeet13)
Scala programming language wins SIGPLAN award

According to the SIGPLAN award committee, “Scala is one of the few programming languages from academia that has had a significant impact on the world as well as on programming languages research."
Shapeless' HLists and how to traverse them

Learn how to achieve working sequence and traverse implementations for any HList and any Applicative.
Yannick Heiber
How to work with JSON in Scala

This tutorial introduces you to the basics of working with JSON in a Scala program, using the uPickle library.
Li Haoyi (@li_haoyi)
cleanframes  - data cleansing library for Apache Spark!

cleanframes is a library that aims to automate data cleansing in Spark SQL with help of a generic programming.
Dawid Rutowicz

PRESENTATIONS

Killing the unit test

In this talk, I’ll explain what Property-based testing and Law testing are, and share some concrete examples from the work we do in BigPanda.
Dor Sever (@dor_sever)

EVENTS

LX Scala & Reactive, Lisbon, Portugal, 4th - 5th July

Use promo code scalatimes_ to get a 40% discount for our readers!
LX Scala & Reactive (@lx_scala)
Lambda World, Cádiz, Spain, October 17th - 18th

Use our link to get a special discount for Scala Times readers!
Lambda World (@lambda_world)
BeeScala, Ljubljana, Slovenia, November 21st - 21rd

Don't miss your ticket for this unique conference!
BeeScala (@BeeScalaConf)

RELEASES

http4s-jdk-http-client

JDK 11+ http client implementation for http4s clients.
stateful-serverless

Research into Stateful Serverless With Akka, Knative, and gRPC.
Lightbend (@lightbend)
cats-retry

A library for retrying actions that can fail.
cats-retry contributors
zio-saga

A library that helps to implement Saga Pattern in purely functional way.
Vladyslav Kopaniev

VARIA

Scala Times banners?

Want one? Click here
THE INTERNET
Scala Times stickers?

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

Need some? SoftwareMill is here, ready to talk and dive deep into your code. .
SoftwareMill





  1. Scala Times Issue #296

    Travis Continuous deployment for your open source library. Publish open source project to Maven with Sonatype. My Way to Scala - part 1. Scala Tuples - Syntax, Declaration, Use case, Examples. Better management of transitive dependencies and conflicts.

  2. Scala Times Issue #295

    Tour of Akka Typed: Event Sourcing. Optional Is the New Mandatory. Visitors - a tale of generalization. Working with Databases using Scala and Quill. Proving Primality with GADTs.

  3. Scala Times Issue #294

    Scraping Websites using Scala and Jsoup. A quiet, attractive new programming language. Domain-driven event sourcing with Akka Typed. Crushing Design Patterns! - Chain of responsibility (Scala). Crushing Design Patterns! - Unnecessary Patterns.

  4. Scala Times Issue #293

    Painlessly passing message context through Akka Streams. Simple Web and Api Servers with Scala. From @Transactional to type-safe, reasonable transactions. 3 Layer Scala Cake. Illustrated guide to Types, Sets and Values.

  5. Scala Times Issue #292

    Human-readable case class diffs. Cats 2.0 migration guide. Top 10 Scala Libraries For Data Science. Kenji Yoshida receives community award. Kelley Robinson receives community award.

  6. Scala Times Issue #291

    Squeezing extra productivity out of Ammonite Scala REPL. Akka family build infrastructure. Learning Akka Typed from Classic. On Eliminating Error in Distributed Software Systems. Error Handling in Functional Applications - from Monad Transformers to ZIO.

  7. Scala Times Issue #290

    Easy Parallel Programming with Scala Futures. Permutive Community Engineering, August 2019. Key things I picked up while working with Scala. Typing the technical interview in Scala. Why Try? - Scala Error Handling.

  8. Scala Times Issue #289

    Dotty (Scala 3) adoption report: easy so far. Scraping and Storing Crypto-currency Prices with Scala and PostgreSQL. Scala Almost Succeeded. Allow significant indentation syntax. Jailbreak Oozie Spark action.

  9. Scala Times Issue #288

    Bootzooka 2019: functional Scala and React. The Science of Functional Programming book. Scala's isInstanceOf is an Anti-Pattern. A Scala “functional programming style” To-Do List application written with Cats. Minutes of the 13th meeting of the Scala Center, Q2 2019.

  10. Scala Times Issue #287

    When do you need Akka Cluster?. Hangman in FP Scala. Make your Google Spreadsheets Scala-ble. Understanding Monoids using real life examples. Scala in the City, London, Simply Business, August 28th.

  11. Scala Times Issue #286

    Tic-tac-toe in FP Scala. How to create Build Pipelines in Scala. Tour of Akka Typed: Message Adapters, Ask Pattern and Actor Discovery. Promise for better Future. Streaming data with Apache Kafka and Akka Streams.

  12. Scala Times Issue #285

    Monad Transformers and Cats MTL. Ratelimiter4s : A functional rate limiting library. A way out of the Jar Hell. Wrapping impure code with ZIO. XXE Attacks in Scala and Play Framework.

  13. Scala Times Issue #284

    Cross-compiling In Scala. IntelliJ Scala Plugin 2019.2. Introducing Scala Cypher DSL. Tame your config. A rate-limiter in 15 lines of code with cats-effect.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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 .

  20. 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.

  21. 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.

  22. 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.

  23. 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.

  24. 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.

  25. 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.

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.