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March 14th, 2019, ISSUE 265

READING

Testing Incrementally with ZIO Environment

In this post, I’m going to show you how to use environmental effects to achieve testability. I hope to demonstrate that environmental effects provide easier and more incremental testability—all without sacrificing teachability, abstraction, or type inference.
John A. De Goes (@jdegoes)
Using Scala in the Cloud: A Guide to Amazon EC2 Instance Types

We ran a number of Scala compilation benchmarks and look at what Amazon instance type is the fastest and what offers the best cost per build.
Iulian Dragoș (@jaguarul)
Finally Tagless - Not Quite Dead Yet

Where one sees death, I see the rise of new, possibly more ergonomic, way of doing dependency injection in Scala.
Daniel Beskin
Functional Testing with Tagless-Final

We’ve explored several methods of testing “real-world” applications that are written in the tagless-final style.
Amitay Horwitz (@amitayh)
Monad Transformers aren’t hard!

Today we crafted couple of monad transformers like OptionT, EitherT, got to know that ListT is not a monad, covered that FutureT cannot be implemented without blocking.
Alexander Zaidel
The Functional Scala Concurrency Challenge

Instead of a circuit breaker, I want you to build a tap, which adjusts the flow of requests continuously through the tap.
John A. De Goes (@jdegoes)
Machine Learning with Scala in Google Colaboratory

In this blog post, we’ll see how to set up Scala to run inside Google Colab, and then take a look at a few examples of machine learning (including with GPU acceleration) with Scala inside Colab notebooks.
Shadaj Laddad (@ShadajL)
Rapid and Highly Scalable Development Using Scala and Lagom

The following blog posts will outline the thought process and the problems solved along the way.
Corey Auger (@coreyauger)
Context bound vs Implicit evidence: Performance

In a recent pull request review at work I suggested using context bound to declare effect capabilities instead of implicit values as this is what I see the most in OSS projects and it has also been my preference for a while.
Gabriel Volpe (@volpegabriel87)
Managing State in Akka Actors

Learn how to get rid of the “var” while maintaining a state as a behaviour change.
Tomer Shaiman (@tshaiman)
Typeclasses for Beginners

As a Scala developer, I had always heard about Typeclasses, and it seemed really hard to understand, but I’ll try to simplify it so much so other beginners can easily understand this great feature in Scala.
Orji Samuel
Simple HTTP Server With Scalatra In 20 Lines Of Code

A short example demonstrating how easy it is to build a web service with Scalatra.
Iev Strygul
Implementing deep learning from scratch. Scala example.

Neural networks can be easily built without dedicated libraries.
Seva Dolgopolov (@seva_dolgopolov)
MapR-DB Spark Connector Performance Tests

One of the questions we had during the implementation of our connector was related to how fast our connector is compared to the official connector.
Nicolas A Perez (@anicolaspp)

PRESENTATIONS

Adapters, Bridges & Typeclasses in Scala

Object Oriented languages implement ad hoc polymorphism via subtypes. In this video we will see how functional languages achieve similar results with type classes.
DevInsideYou (@DevInsideYou)

EVENTS

ScalaUA, Kiev, Ukraine, March 29-30

Use promo code ScalaTMS%_ScAlAUA-2019-29-30 for 20% discount for our readers!
ScalaUA (@ScalaUA_Conf)
Scalar, Warsaw, Poland April 5-6

Join the next edition of the largest Scala conference in central Europe!
SoftwareMill (@softwaremill)
flatMap(Oslo), May 8-9

Use promo code SCALATIMES for a discount for our readers!
flatMap(Oslo) (@flatmaposlo)
CFP for Lambda World, Cádiz, Spain, October 17th - 18th

Deadline for submissions is June 1st.
Lambda World (@lambda_world)
CFP & free ticket for BeeScala, 21-23 November, Ljubljana

Answer the question: "What is the idea behind the BeeScala name?", send your reply to info@bee-scala.org by 31st of March. For some lucky person, there's one free ticket waiting!
Bee Scala (@BeeScalaConf)
CFP for NEScala 2019

This year, NEScala is back in Philadelphia, April 1st through 3rd.
NEScala (@nescalas)

RELEASES

borer

Idiomatic CBOR (de)serialization in Scala.
Mathias Doenitz (@sirthias)
Dsl.scala

A framework to create embedded Domain-Specific Languages in Scala.
Yang Bo
quill 3.1.0

Quill provides a QDSL to express queries in Scala and execute them in a target language. Version 3.1.0 adds support for Oracle, Cassandra + Lagom, and improved modularization.
Quill contributors

VARIA

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