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January 30th, 2020, ISSUE 312


Introducing error reporting in optics

A frequently requested feature is the ability to report why an optic failed. It is particularly crucial when you build a sophisticated optic.
julien truffaut (@JulienTruffaut)
The complexity of Java comparators, and the simplicity of Scala sort by

Sorting in Java vs sorting in Scala.
Alonso Del Arte (@alonsodelarte)
GraphQL in Scala with Caliban - Part 1

Small intro to Caliban - a functional GraphQL backend in Scala.
Pierre Ricadat (@ghostdogpr)
Tidying up your SBT file with Scala

A right toolbox to manage your dependencies and compilation options with SBT on a simple and clean way.
Manuel Rodríguez
Dependency injection with Reader Monad in Scala

One of the specific Functional Programming patterns: DI without gymnastic.
λ.eranga (@itseranga)
Etcd watch API integration with scala and cats-effect

An interaction with etcd watch API with scala and cast-effects IO monad.
λ.eranga (@itseranga)
Guide to Trait Linearisation in Scala

Do you understand in which order your overriden methods are being called?
Sayan Chakraborty


Data Juggling - Part 2 - Homegrown #Lenses (#Monocle - Part 1)

In this video we are going to implement our own Lenses and drive our design towards Monocle - a library which offers useful data manipulation tools called Optics. By the end of the video we will replace our lenses with Monocle.
Vladyslav Pekker (@DevInsideYou)
Managing Blocking in Akka

A four-minute video explaining why it is bad to block inside an actor, and how you can use custom dispatchers to manage blocking when you cannot avoid it.
Arnout Engelen (@raboofje)


Scalar, March 19th-21st 2020, Warsaw, Poland

Get ready for the workshop-driven FP event in Poland!
SoftwareMill (@scalarconf)
ScalaUA, April 3th-4th 2020, Kyiv, Ukraine

CFP is on! 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)



Cache in Scala with cats-effect.
Yaroslav Klymko (@t3hnar)

Redis client built on top of Cats Effect, Fs2 and Lettuce.
redis4cats contributors
chimney 0.4.0

Scala library for boilerplate-free data transformations. New version brings a bunch of new features.
chimney contributors


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