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June 20th, 2019, ISSUE 279

READING

Thread shifting in cats-effect and ZIO

ZIO’s .on and cats-effect’s .evalOn might seem to do the same, but they don’t. Remember to pay attention to the thread pools you are using!
Adam Warski (@adamwarski)
How to work with HTTP JSON APIs in Scala

This tutorial will walk you through how to access JSON HTTP APIs in Scala, building up to a simple use case: migrating Github issues from one repository to another using Github's public API.
Li Haoyi (@li_haoyi)
ZIO with http4s and doobie

An example of how to put together a reactive application with functional programming libraries.
Wiem Zine (@WiemZin)
Optimizing CI build times for Scala projects

At some point your integration tests suite may get super slow. Here are some techniques how to design and run them so you don't get stuck waiting unnecessarily.
Manuel Bernhardt (@elmanu)
The False Hope of Tagless-Final in Scala

In this post, I will argue that the many claims made about tagless-final in Scala are not entirely true, and that the actual benefits of tagless-final come mostly from discipline, not from so-called effect polymorphism. After this detailed analysis, I will conclude the post by providing a list of concrete recommendations for developers who are building functional Scala libraries and applications.
John A De Goes (@jdegoes)
Korolev. Slimming pill for Web

Learn about the Korolev project - how it runs a single-page application on the server side, keeping in the browser only a bridge to receive commands and send events. The page loads instantly and works fast, because it does a minimal amount of computation.
Aleksey Fomkin (@yelbota)

PRESENTATIONS

Homegrown Scala Collections - Part 34.1 and 34.2 - foldRight

In this video we will implement Lists/Stacks and learn about the hidden treasures of foldRight. This video is split into two parts.
DevInsideYou (@DevInsideYou)
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Lambda World (@lambda_world)
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