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February 11th, 2021, ISSUE 365

READING

Coding Adventures with Party Parrot Game

Type safe, party hard and travel the world with Party Parrot! Solve fun programming puzzles, bookmark the game, and join us on 13th of February.
SoftwareMill (@softwaremill)
Scala Cats Contravariant Functors

In this post, we’ll talk (again) about Functors — the ones from Scala Cats library, but not the classic Functors like we all know and love, we’ll cover a bit different kind of Functors called Contravariant Functors — depicted in Cats itself as a type class named just that: Contravariant.
Krzysztof Grajek (@grajo)
From First Principles: Why Scala?

Learn why all Languages lead to Scala.
Li Haoyi (@li_haoyi)
Pure Functional Stream processing in Scala: Cats and Akka – Part 1

This is the first part in a series of post where I explore how to connect pure functional programming using Cats and Streaming with Akka Streams.
Mihai Safta (@saftacatalin)
Idiomatic Error Handling in Scala

What's the best way to handle errors? Exceptions? Try? Either? Validated? It depends!
Daniel Ciocîrlan (@rockthejvm)
Stop Letting Your Tests “Make” Your Luck

At Riskified, we wrote a small Scala testing framework that automatically generates random inputs. It makes our lives a bit easier, leaving us free to focus on what really matters in our tests.
Asaf Manshary
How To Implement Streaming Microservices Using ZIO and Kafka

I will cover the basics of ZIO, ZIO Streams, and finally, the process of implementing streaming microservices using functional programming techniques.
Aleksandar Skrbic (@skrbic_a)
Adam Rosien: Cheese Pairings For Effects - The Scala Logs

A new episode is up with Adam Rosien, talking about his new book Essential Effects.
The Scala Logs (@TheScalaLogs)
Union and Intersection Types in Scala 3

Scala 3 aka dotty comes with a lot of new types. Union, Intersection, Opaque etc. Let’s understand union and intersection types in detail.
Ayush Mittal
Programming in Scala, Fifth Edition

PrePrint PDF update of Programming in Scala is now available. Use code SCALATIMESPINS5 for 15% off. Offer expires 2/28/2021
Artima, Inc. (@ArtimaInc)

EVENTS

Scala Love in the City, 13th February, Online Event

Come, come, come! Have a wonderful time together voicing solutions to problems as well as discussing education and Scala careers in the new millennium.
Scala Love (@scala_love)
Lambda Days 2021, 16th - 19th February, Virtual Event

Use code ScalaTimes15 for a 15% discount for our readers! 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)
Unlock the Secrets of Scala 3 Macros, 24th February, online event (EST)

If we look deeper into Dotty Mirrors and inline, we discover an incredibly deep feature-set that elegantly solves a plethora of meta-programming problems.
Alexander Ioffe (@deusaquilus)
ZIO World, 11th March, Online Event

Join ZIO users and contributors for the inaugural ZIO World, which reveals ZIO 2.0, providing inspiration and new opportunities to create the most powerful reactive applications on the JVM. FREE of charge for all ZIO Contributors and Users.
Ziverge (@zivergetech)

RELEASES

korolev 0.17.0

Single Page Applications running on the server side. Now with Http4s/Fs2 support.
korolev contributors
Laminar

Simple, expressive, and safe UI library for Scala.js.
Nikita Gazarov (@raquo)
natchez-http4s

Glorious integration layer for Natchez (a functional tracing library) and Http4s.
Rob Norris (@tpolecat)





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    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.


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