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August 10th, 2018, ISSUE 234

READING

Reverse State Monad in Scala. Is it possible?

Summer fun: binding your mind backwards with the reverse state monad!
Vladimir Pavkin (@vlpavkin)
Typedapi or how to derive your clients and servers from types

Continuing the Swagger theme from last week, here's how to implement a type-safe HTTP API description library
Paul Heymann
Testing in the wild

Real-world tips on how to use specs2 + ScalaCheck, straight from the specs2 author!
Eric Torreborre (@etorreborre)
The Infamous Cake Pattern for Dependency Injection in Scala - Part 3

This is the 3/3 part of the video series in which we are going to learn about the infamous cake pattern, which is commonly discussed in the context of dependency injection. In order to explore the intricacies of this pattern we are going to write a massively over-engineered todo app with a terminal delivery mechanism and an in-memory persistence layer.
DevInsideYou (@DevInsideYou)
Akka HTTP request/response scope operations, vs. Deferred operations

The next installment in the Akka HTTP series: working with Futures, and how they integrate in the Request-Response cycle. With pictures!
Richard Imaoka (@richardimaoka)
Akka anti-patterns: too many actors

Can you have too many actors? Turns out that's the case!
Manuel Bernhardt (@elmanu)
Using ZIO with Tagless-Final

Can you use the ZIO bifunctor and tagless final? Sure! John shows you how.
John de Goes (@jdegoes)
Data Modeling in FP vs OOP

How to replace polymorphism in Scala with a "functional" approach, on the example of data hierarchy modeling. This might be a start to an interesting series!
John de Goes (@jdegoes)
sbt 1.2.1 patch release

Use 1.2.1, don't use 1.2.0 - there were some binary compatibility issues. All the goodies of the 1.2 sbt series remain!
Eugene Yokota (@eed3si9n)
Introduction to mockito-scala

Mockito might not be the most popular testing library among Scala programmers, but it's sometimes useful nonetheless. Now with a Scala-friendly wrapper.
Bruno Bonanno (@bbonanno)
Http4s With Ross Baker

Something to listen to on the road, an interview with http4s contributor Ross Baker on writing purely functional HTTP services.
Adam Bell (@corecursive)
Kinds of types in Scala, part 1: types, what are they?

New mini-series by Mateusz: an introduction to types and the related concepts, plus how they map to Scala
Mateusz Kubuszok (@MateuszKubuszok)
The missing findM and collectFirstM methods in cats.Foldable

A specific problem: finding the first collection item when dealing with effectful types, and the road to a functional solution
Henry (@EnergyThen)

EVENTS

Lambda World Seattle, September 17th - 18th

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47 degrees (@47deg)
Lambda World Cádiz, Spain, October 25th - 26th, 2018

Use promo code STLW18 for Scala Times readers to get 10% discount!
47 degrees (@47deg)
Scala Wave, September 6th - 8th, 2018, Gdańsk, Poland

Use code scalatimes_10, registration with special 10% off discount, to use on the conference day, ends on June 30th!
Scalac (@scalawavepl)
Scala Italy, September 14th-15th, Florence

Use promo code SCALATIMES_U2N for a 10% discount for Scala Times readers!
Scala Italy (@ScalaItaly)
LambdAle, London, September 1st

Use promo code SCALATIMES for Scala Times readers to get 10% discount!
LambdAle (@lambd_ale)
Win a ticket to Scala Italy!

Enter the competition to win a free ticket.
Signify Technology (@Signify_Tech)

RELEASES

Typelevel http service definition DSL

Another development in the typelevel HTTP service definition DSLs!
Tinkoff Credit Systems
Simple Kafka Client for fs2

Functional Kafka using FS2
Ovotech
A static site generator for Scala

For all your static website needs
Anatolii Kmetiuk (@AKmetyuk)
2.13.0-M5 release train

2.13 is coming, don't miss the train!
Seth Tisue (@SethTisue)
Mercator: a small macro for automatically creating typeclass evidence for monad-like types

No-runtime-overhead, no-boilerplate library for working with abstract monad-like types
Jon Pretty (@propensive)

VARIA

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