Static assets in an eventually consistent webapp deployment

The Problem

Deploying a high traffic website with zero downtime is a challenge – there’s a natural tradeoff between:

  • Performance and cacheability.
  • Getting updates versions of the application live.

The approach you use to manage your static assets plays a big role in this.

This post explains how we dealt with the challenges in our move from the data centre to a multi region highly available cloud-based architecture.

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A Journey into Extensible Effects in Scala

A Journey into Extensible Effects in Scala

This article is an introduction to using the Scala Eff library, which is an implementation of Extensible Effects. This library is now under the Typelevel umbrella, which means it integrates well with popular functional programming libraries in Scala like Cats and Monix. I will not touch on the theoretical side of the concept in this post. Instead, I will be using code snippets to describe how you would introduce it to an existing Scala code base. This should hopefully improve extensibility and maintainability of the code. As part of this, I will demonstrate how to build a purely functional program in Scala using concepts such as Either, Writer and Reader.

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Lean QA (aka QA Ops)


Developers have – with the advent of DevOps – been working more and more in Operations and Infrastructure. Testers however, have not.

Thus far, the testing personnel have been mostly or wholly assigned to application testing work. As SOFTWARE testers, we have only worked on software – and then mostly only on application software.

I pose the questions: What about infrastructure as code? Should that not be explicitly tested?

And: if Testers are meant to be testing the system, why then have they not explicitly been testing the whole system, infrastructure included?

I am going to make a case here for including QA in Operations and Infrastructure, by clarifying how I see the QA fitting in the DevOps world. Continue reading

AWS API Gateway, Lambda and Swagger


With this article you will be able to build


Building upon

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My Journey in a UI Project (aka front-end is the new back-end)

In this blog post, I share my recent experience in a UI project, as a developer with limited past experience in UI development. I published this internally on REA Group’s wiki a while back to foster interest in UI projects from a broader set of developers – highlighting that solid engineering is a big part of contemporary UI development.

This is not specific to REA, hence I was keen to share this journey externally on our blog. Continue reading