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March 15th, 2018, ISSUE 213

READING

Generic Programming and Shapeless with Miles Sabin

A new episode of the CoRecursive w/ Adam Bell podcast.
Miles Sabin, Adam Bell (@milessabin)
Implementing an event-driven HTTP server with Scala Native

In this post I'm going to introduce Scala Native by using it to write a simple HTTP server using a C library called libuv.
Chris Birchall (@cbirchall)
Survey on Swagger with Akka HTTP

TL;DR) You can use Swagger with Akka HTTP and get some benefit from Swagger, but the workflow is not fully automated with existing tools.
Richard Imaoka (@richardimaoka)
AST-free JSON parsing

Provisional benchmarks of AST-free serialization puts my WIP branch of uPickle about ~40% faster than circe on my current set of ad-hoc benchmarks, if the encoders/decoders are cached.
Li Haoyi (@li_haoyi)
5 steps of creating your very first Type Class in Scala

In this blog post you will learn about how to implement your first type class, which is fundamental language feature in the icon of the functional programming languages — Haskell.
Adam Gajek (@adam_gajek)
Scala: try-with-resources

Despite the fact that resource management is a well-known subject, there are still many mistakes around it.
Dmitry Komanov (@dkomanov)
Avoid pattern matching with List in Scala

recently debugged a strange issue which seemed to appear out of nowhere™. It all came down to a that we used List in a match while the methods signature was changed from List to Seq.
Anton Fagerberg (@AntonFagerberg)
Understanding Functor and Monad With a Bag of Peanuts

When I started coded in Scala I heard someone saying List, Option, Future etc. are all monads and functors. I wanted to understand what exactly is a monad or a functor.
Sujit Kamthe (@sujeet100)
Announcing discuss.akka.io!

We’re pleased to announce a new way to communicate with the core team and communities around the Akka projects (including Akka HTTP, Alpakka the various persistence plugins and all other community projects), as well as downstream projects such as Play and Lagom.
Akka Team
Deploying a Medical Time Series Model using Zeppelin Notebooks and SKIL

One of the largest barriers to deriving value from machine learning (ML) in clinical and other enterprise settings is the handoff from data science to production deployment. We have shown how SKIL provides a single environment in which to create, analyze, and deploy models for production quickly and easily, easing this handoff.
Briton Park

EVENTS

ScalaUA, April 20-21, 2018, Kyiv, Ukraine

Use promo code "ScalaTimes_ScalaUA-2018-20-04" for 5% discount!
ScalaUA
Scala Sphere, April 15-17, Kraków, Poland

Use promo code sphereit-2018-scalatimes for 10% discount for Scala Times readers!
Scala Sphere (@ScalaSphere)
Scalapeño 2018 CFP, July 2, Beer Sheva, Israel

Send your proposal before 2018.04.01.
Scalapeño
Blockyard Conference, April 13, Gdańsk, Poland

Use our promo link to get a 40% discount for Scala Times readers!
Blockyard

RELEASES

akka-http-json 1.20.0

akka-http-json provides JSON (un)marshalling support for Akka HTTP via Argonaut, circe, Jackson, Json4s, Play JSON, uPickle, and avro4s.
akka-http-json contributors
pulsar4s

Idiomatic, typesafe, and reactive Scala client for Apache Pulsar
Stephen Samuel
sbt-close-watch

This is an sbt plugin that aims to lower the latency between file system events and sbt tasks. It replaces the default watch service with a more highly optimized service that works well on all platforms.
Ethan Atkins
scalajs-react 1.2.0

React 16 support and adherence, new shapes, type-safe and purely-functional AJAX + much more.
scalajs-react contributors
Dsl.scala

A simple framework for creating embedded DSL in Scala control flow.
Yang Bo
kafka-streams-scala 0.2.0

This release brings implicit Serdes, more typesafety, misc refactorings.
Lightbend
Akka HTTP 10.1.0

The new client pool implementation introduced in 10.0.11 is now the default, Experimental artifacts are available for Scala 2.13.0-M3, no more Akka 2.4.x support, and much more updates.
akka-http contributors
Dotty 0.6.0 and 0.7.0-RC1

These releases serve as a technology preview that demonstrates new language features and the compiler supporting them.
Dotty contributors
Travesty 0.9

A library for generating structural diagrams of your Akka Streams. First of all, supported Akka versions have been extended up to 2.5.11. Most importantly, Travesty can now generate diagrams from any graph, not only RunnableGraph / Graph[ClosedShape].
Mikołaj Koziarkiewicz (@mikolak_net)

VARIA

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