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December 19th, 2019, ISSUE 305


Alpakka Kafka -  an open-source Reactive Enterprise Integration library for Java and Scala

Read about the origins of the library and what I've learned about contributing to Open Source.
Krzysztof Ciesielski (@kpciesielski)
Beyond Liskov: Type Safe Equality in Scala

How a "safer" equality check is just one of many features that go against the principles that underlie any type system with subtyping, and achieving it requires a fundamental re-thinking of what it means to be "type safe".
Li Haoyi (@li_haoyi)
Scala 2 Roadmap Update: the Road to Scala 3

Scala 3 instead of Scala 2.14.
Scala Team (@scala_lang)
Explicit nulls are in!

In the Dotty master branch, there is now a concept of “explicit nulls”.
Mark "Justin" Waks (@jducoeur)
Functional Scala London 2019: Day 1

A short summary of the talks presented on the first day of the event.
Juliano Alves (@vonjuliano)
Leveraging Monoids for More Powerful Summarization

The discussion on the power of folds.
Adam Rosien (@arosien)
Scala Server Toolkit – Creating HTTP Server

How to initialize and start a simple HTTP server using http4s.
Jakub Janeček (@jakubjanecek)
How to dynamically inject the implementation for ZIO with MacWire

How to wire the implementation dynamically on application start (defined in a configuration file)?
Pascal Mengelt
Demystifying Functional Programming (Part 1)

What are Pure Functions?
Harshpreet Singh
Building a scalable reactive ingestion pipeline to ingest data in a Graph DB

Ingestion pipeline implemented end to end.
Dhananjay Ghanwat
Get started with ZIO Test

A zero dependency Scala library for testing.
Wiem Zine (@WiemZin)
Quick start guide to Spark with Databricks

Getting results from Spark in minutes instead of days.
Scott Johnson
Being Explicit on Scala Implicits

Implicits in their natural habitat.
Shantanu Kamath
Functional retry handling with cats-retry in Scala

How to implement a functional retry mechanism in Scala.
Hiroki Fujino


Lambda Days, February 13th -14th 2020, Kraków, Poland

Draft paper submission by January 13th.
Lambda Days (@LambdaDays)
ScalaUA, April 3th-4th, 2020 Kyiv, Ukraine

CFP is on! Also: Super Early Bird tickets are available on website till 2019.12.31, and Wholesale 10+ tickets are available till 2020.04.02.
ScalaUA (@ScalaUA_Conf)
Scalar, March 19th-21st, 2020, Warsaw, Poland

Don't miss the CFP, open until Jan 1st! Get ready for one of the biggest Scala conferences in Europe!
SoftwareMill (@scalarconf)


cats-retry - v1.0.0

Simplify the module structure and introduce alleycats-retry.
Luka Jacobowitz (@LukaJacobowitz)

JSON RPC client for Bitcoin, Ethereum and Omni.
Jendrik Poloczek (@madewithtea)

Scala DSL for Unit-Testing Processing Topologies in Kafka Streams.
Jendrik Poloczek (@madewithtea)
Announcing Scala.js 1.0.0-RC2

Dropped support for sbt 0.13 and Scala 2.10, 2.11, 2.12.0, Access to the global scope instead of the global object, Members can only be accessed with a statically known name which is a valid JavaScript identifier, and many more fundamental changes!
Scala.js contributors (@scala_js)
Play 2.8.0 Released!

Many new features and continuation of efforts to make Play more modular, flexible, and secure.
Play Framework Team (@playframework)
Lagom 1.6 Released

Akka Persistence Typed, Projections Stop/Resume, Akka Jackson support and more.
Lagom contributors


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