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December 6th, 2018, ISSUE 251

READING

Scala Numerical Performance with Scala Native and Graal

That post focused on the style of Scala code used and how that impacted the performance.
Mark Lewis
SBT Plugin - How to make it, debug it, improve it?

A detailed step-by-step guide.
Leo Benkel (@LeoBenkel)
Better than IO, part 1

This part covers MTL style.
Yuriy Netesov (@yuriynetesov)
Scala and Slick - An Introduction

In this article, I am going to explain working with Scala and slick, this is a tutorial to help beginners get a hang of slick as well as introduce to the concept of Scala Programming.
Adekunle Babatunde
EitherT

EitherT is a data type offered by cats, and despite the great documentation, I don’t think the EitherT docs do a great job explaining why something like this exists.
Ben Sheron
Category Theory for Programmers: Scala Edition 1.1-RC

First (pre)release of the Scala Edition! Contains code snippets in both Haskell and Scala (one after the other).
Bartosz Milewski (@BartoszMilewski)
Shape-dependent computations in Scala … and Agda!

In this post we will solve a little programming problem, mainly with the excuse of talking about dependent types.
Juan
Deploying Scala.js to the Web with Netlify

Last week I set up a Scala.js project to automatically deploy the master branch from github to a website running on Netlify, and was pleasantly surprised at how easy and straightforward it all was.
No Fun Allowed
Error handling in Http4s with classy optics – Part 2

I recently gave a 20 minutes talk on classy optics at the unconference of Scale by the Bay where I also talked about this error handling technique and on my way back home I was still thinking of different ways of doing this. So, after some exploratory work, I came up with a few different alternatives.
Gabriel Volpe (@volpegabriel87)
Scala exercises: cats-effect

Enjoy solving worker pool with load balancing and race for success to understand the practical side of cats-effects!
Oleg Pyzhcov
The Little Typer With Dan Friedman and David Christiansen

You can write more correct software and even rigorous mathematical proofs. Prepare for some mind stretching.
CoRecursive
Using Scala at the BBC

As part of the lead up to Scala eXchange London, we sat down with Phoebe Greig and Duncan Walker from BBC about their experience in adopting Scala. Read the interview here.
Skills Matter (@skillsmatter)
ScalaX2gether Community Day 2018

Following 2 days of awesome fun at Scala eXchange 2018, jump in right away with the latest technology on hand, join fellow ScalaX attendees and some of the most talented coders and experts, for ScalaX2gether and create something amazing! Register for FREE!
Skills Matter (@skillsmatter)
Imposing invariants in Scala

This post discusses different FP and OOP techniques to leverage types in order to model some constraints.
Carlos Teixeira
What Does an Ideal Data Scientist’s Profile Look Like?

Because of the need to implement algorithms from scratch and deploy ML models in big data environments, relevant languages such as C++ and Scala are also important.
George Liu
Top link of November: Explore Witnesses as an Alternative to Implicits

Martin's proposition has started quite a hot discussion, becoming the most visited link at Scala Times. Time to revisit!
Martin Odersky (@Odersky)
Aecor - Purely functional event sourcing in Scala

An introduction to the series.
Vladimir Pavkin (@vlpavkin)
Aecor - Purely functional event sourcing in Scala. Part 1

The first part focuses on defining entity behavior.
Vladimir Pavkin (@vlpavkin)

PRESENTATIONS

Homegrown Scala Collections - Part 16 - Stacks & related JVM flags

In this video we are going to start a conversation about advanced tail call elimination techniques.
DevInsideYou (@DevInsideYou)

EVENTS

Scalar, Warsaw, Poland April 5-6, 2019

Join the next edition of the largest Scala conference in central Europe!
SoftwareMill (@softwaremill)
Lambda Days, Kraków, Poland, February 21-22, 2019

Use promo code SCALArlz10 for a 10% discount for our readers!
LambdaDays (@LambdaDays)
$100 discount for Scala Times readers for "Functional Scala" training by John A De Goes in London

Use code "ScalaTimes" and join the training on Dec 10-12.
Signify Technology (@Signify_Tech)
What are the experts keen to share at Scala eXchange London 2018

“A conference is more than just a series of talks. It's about community, friendship, and having fun. You can't replicate that by watching videos." - Noel Welsh on why he is speaking at ScalaX again this year. Check out what others amazing speakers are most looking forward to the conference! Read more.
Skills Matter (@skillsmatter)

RELEASES

scala-typed-holes

This is a Scala compiler plugin to emulate the "typed holes" feature of Haskell, Idris, Agda, etc.
Chris Birchall (@cbirchall)
Announcing Dotty 0.11.0-RC1

Opaque Type Aliases, Worksheet Mode Support in Visual Studio Code, Various IDE improvements, and much more!
Dotty contributors

VARIA

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