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April 12th, 2018, ISSUE 217

READING

A Functional Interface for Key/Value Store

In a stream-based store interface built with Functional Streams for Scala (fs2) we can transfer the stream of bytes coming from SFTP into the stream of bytes going into S3 without ever storing these bytes in the local filesystem.
Stew O'Connor (@StewOConnor)
Defeat your 99th percentile with speculative task

Speculative task has saved the day in our case. It has reduced the last percentiles. At the same time we haven’t observed increase load to Redis. In reality the speculative call takes place only once per a few hundreds calls.
Bartosz Jankiewicz
cats-infographic

This is an OmniGraffle 7 diagram of the Cats typeclass hierarchy, shareable under the CC-BY-SA 4.0 license.
Rob Norris (@tpolecat)
Synchronous or asynchronous, and why wrestle with wrappers?

Have you ever wondered why you have to wrestle with CompletableFutures instead of “just writing code” like in the old days? Is it only for performance? Or maybe it’s just a fashion? Let’s find out!
Adam Warski (@adamwarski)
Running Spark on a Cluster: The Basics

We’ll cover how to start up a Spark cluster using the Flintrock command-line tool, and we’ll run a simple word count example using the spark-shell, Spark’s interactive REPL.
Heather Miller (@heathercmiller)

PRESENTATIONS

Talks from Scalar Conference 2018

First videos are available, come and check for updates regularly!
SoftwareMill (@scalarconf)

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)

RELEASES

GitHub - battermann/pureapp

A principled and opinionated library for writing purely functional, easy to reason about, and stack-safe sequential programs partly inspired by Elm, scalm, and scalaz's SafeApp.
Leif Battermann (@leifbattermann)
reactive-kafka 0.20

Exposed metrics and ability to set rebalance listener plus some minor fixes.
reactive-kafka contributors
sbt 1.1.4 hotfix

Fixes triggered execution on macOS and quite a few more issues.
sbt contributors

VARIA

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