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September 17th, 2020, ISSUE 344

READING

Can we build better?

Can we have a dependable and reproducible way to build and test scala applications locally and in a CI pipeline?
Adam Gordon Bell (@adamgordonbell)
Algebra and Parametricity

Reasoning using parametricity requires a polymorphic function from which we can derive free theorems. In this post, we are going to look at the algebra of these polymorphic functions and how we can arrive at a concrete value for them.
Tony Morris (@dibblego)
How to Deploy a Scala Application to AWS Lambda

I'll demonstrate how to deploy a Scala application to AWS Lambda, step by step.
Daniel Ciocîrlan (@DanielCiocirlan)
5 lessons learned from my continuing awesome journey with ZIO

Learn about performing non heap-safe recursion, running a side-effect alongside an effect that is repeated, unintentionally using TestClock in periodic assertion code, forgetting to map between ZIO Test assertions, and interrupting a fiber that originates from a Managed#Acquire scope.
Natan Silnitsky (@NSilnitsky)
Scala 3 - A community powered release

This blog aims to capture what it takes to coordinate the Scala 3 release efforts and to invite you to help us make it a success!
The Scala Center team (@scala_lang)
Apache Kafka and ZIO

This article will explain why you want to use Apache Kafka in your project, Core Concepts about Kafka, and how you can use it with the ZIO Kafka library.
Aleksandra Holubitska (@Oleksandra_A)
Akka HTTP loves JSON: 3 Libraries You Can Integrate into Akka HTTP

In this article we'll address not one, but 3 different ways to handle JSON in Akka HTTP.
Daniel Ciocîrlan (@DanielCiocirlan)
4 Ways to Make Change in Scala

With that in mind, this blog post about 4 different ways to solve one of the exercises, and what they taught me, not just about Pure FP, but about teaching Pure FP.
Joe Warren (@hungryjoewarren)
Top Link of August: An Introduction to Functional Design

Definitely the most popular article last month, don't even think about skipping this one!
John A. De Goes (@jdegoes)

PRESENTATIONS

Programming in Scala for beginners at university level - week 1

Open Scala lectures in Swedish by Björn Regnell at Lund University, Sweden
Björn Regnell
Hands on Scala With Li Haoyi

Discussion about upcoming "Hands on Scala" book, as well as Mill and Ammonite.
Scala Love (@scala_love)
Tagless Final - Part 10 - main-postgres-skunk (The Big Rewrite)

In this video we will finish the skunk layer. We will also create and run a postgres database via docker and docker-compose.
DevInsideYou (@DevInsideYou)

EVENTS

Functional Effects, September 23rd-24th, Online training

In this course, Scala developers will learn how to solve complex problems in asynchronous, concurrent programming using the ZIO library. Use code "ScalaTimes10" to receive 10% off at the checkout.
John A. De Goes (@jdegoes)
Virtual Scala, September 24th, Online Meetup

Talks: "Multi-Tenancy at Scale" by Sahil Anand, and "Using Aspects to transform your codes with ZIO Environment" by Adam Fraser. The meetup will take place online via GoToWebinar on the 24th of September, 2020 at 19:00 GMT+2.
Ziverge (@zivergetech)
Functional Scala CFP

The CFP closes on October 15th
Ziverge (@zivergetech)
Functional Design, October 20th - 22nd, Online training

In this course, developers will learn how to write simple functional solutions to everyday business problems, without jargon and without type classes. Use code "ScalaTimes10" to receive 10% off at the checkout.
John A. De Goes (@jdegoes)
The Rise of Loom and the Evolution of Reactive Programming, October 22nd, Online meetup

On Thursday, October 22nd at 5:00 PM John A. De Goes will be giving a talk to the online meetup of ZIO London.
John A. De Goes (@jdegoes)
Functional Data Modeling, November 18th - 19th, Online training

In this course, developers will learn how to use functional Scala to construct simple, precise, and flexible models of any business domain. Use code "ScalaTimes10" to receive 10% off at the checkout.
John A. De Goes (@jdegoes)
ZIO Hackathon, November 20th-21st, online event

Attendees of ZIO Hackathon 2020 will be able to attend talks on ZIO projects from leading open source contributors, as well as receive expert mentorship in contributing features, bug fixes, and documentation enhancements to the ZIO ecosystem of libraries.
Ziverge (@zivergetech)
Functional Scala, December 3th-4th, London

Learn the critical topics you need to excel as a Scala developer, and celebrate the Scala programming language and community.
Ziverge (@zivergetech)
Scala 3 for Scala 2 developer, December 8th - 10th, Online training

In this course, developers who are already familiar with Scala 2.x will get a high-speed introduction to all the changes coming in Scala 3, including semantic changes, syntactic changes, new features, and dropped features. Use code "ScalaTimes10" to receive 10% off at the checkout.
John A. De Goes (@jdegoes)
Functional Scala Megapack (4 workshops)

Functional Effects + Functional Design + Functional Data Modeling + Scala 3 for Scala 2 developers. Use code "ScalaTimes10" to receive 10% off at the checkout.
John A De Goes (@jdegoes)

RELEASES

Akka Projections 1.0.0

In Akka Projections you process a stream of events or records from a source to a projected model or external system. Each event is associated with an offset representing the position in the stream. This offset is used for resuming the stream from that position when the projection is restarted.
Akka Team (@akkateam)
caliban 0.9.2

Functional GraphQL library for Scala. Upgraded zio-query to 0.2.5, bringing a x2 speed improvement in the "simple" benchmark scenario, applied the GQLName annotation properly to fields, improved schemas inference, and many more updates!
caliban contributors





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