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February 20th, 2020, ISSUE 314

READING

Using Dotty Union types with Akka Typed

Based on what I’ve read and experimented with, it’s obvious that Dotty brings a lot of features that enable writing more concise and clearer code.
Eric Loots (@lootser)
About Variance

Variance is a complicated topic but it does not need to be. Its main purpose is to provide us with typesafe substitution but also with improved type inference.
Francis Toth (@francistoth)
My FP Journey

A story of a journey through paradigms and libraries.
Zach Albia
Creating a dead simple CountDownLatch with ZIO

We created a simple and non-blocking CountDownLatch with very little code, which is valuable for making our test suite more robust.
Amitay Horwitz (@amitayh)
ZIO STM: CountDownLatch in two lines

Here's a follow-up to the previous post, with an alternative approach.
Ferdinand Svehla (@fsvehla)
2019 Scala Developer Survey

The Scala Center, the LAMP, and Lightbend would like to know more about your habits as a Scala programmers and to identify the pain points of your workflow.
Scala Center (@scala_lang)
Benchmarking Web Services using GraalVM Native Image

In a previous post I discussed the steps needed to compile a http4s web service to an executable with GraalVM Native Image. It’s natural to ask what tradeoffs are made by going this route instead of using the JVM. In this post I present several benchmark results I obtained comparing the Native Image executable to the running on the JVM.
Noel Welsh (@noelwelsh)
Operating Akka Clusters using KUDO

The combination of extensible, open, dynamically scalable infrastructure (Kubernetes plus KUDO), with an extensible, open stateful runtime (Akka) opens up amazing possibilities.
Michael Beisiegel (@realmbgl)
Testing with Functional Programming in Scala

How you can apply functional programming concepts to gain confidence about your API code with minimum effort.
Leonti Bielski
Deploying a full stack Scala application on Heroku

Share a lot of code between your frontend and your backend, avoiding a lot of hassle in writing twice model definitions and validations.
Antoine Doeraene (@doe_antoine)
Elasticsearch Geo-point queries with Scala

Using Elasticsearch geo_point queries with Scala application.
λ.eranga (@itseranga)

PRESENTATIONS

Data Juggling - Part 5 - Curry-Howard-Lambek Correspondence

This video is an overview of the famous isomorphism between mathematical proofs, computer programs and category theory.
DevInsideYou (@DevInsideYou)

EVENTS

Stairway to Scala Workshop, March 16-20, 2020, San Damiano, CA, USA

Use code: SCALATIMESMAR20 to get -10%.
Artima, Inc (@ArtimaInc)
Scalar, March 19th-21st 2020, Warsaw, Poland

Get ready for the workshop-driven FP event in Poland!
SoftwareMill (@scalarconf)
ZIO Hackathon, March 22nd-23rd 2020, Warsaw, Poland

Over the course of two days, we will share and learn about ZIO and related projects; chat about functional programming, functional Scala, and much more; work on fun projects; and get to know one another.
Ziverge (@zivergetech)
ScalaUA, April 3th-4th 2020, Kyiv, Ukraine

Wholesale 10+ tickets are available till 2020.04.02.
ScalaUA (@ScalaUA_Conf)
flatMap(Oslo), May 14th-15th 2020, Oslo, Norway

The call for papers are open til until 1st of March. Also, user our link for a special discount for Scala Times readers!
flatMap(Oslo) (@flatmaposlo)
Scala Swarm 2020, June 18th-23rd 2020, Porto, Portugal

Ticket sale is now open, come quick and grab your ticket to this unique event!
ScalaSwarm (@ScalaSwarmConf)

RELEASES

zio-grpc

ScalaPB meets ZIO: write purely functional gRPC services and clients using ZIO.
zio-grpc contributors
typelevel-library.g8

Template for starting FP libraries ready to be published.
Alex Nedelcu (@alexelcu)

VARIA

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