Blaz Merela,
a problem solver.

AWS & PostgreSQL; Elixir & Python; iOS.

Recent posts

A royal road to Kubernetes on AWS - part 0

This will be the first in a series of posts on how to set up a production-grade Kubernetes (k8s) cluster on AWS EKS. The series aims to be a piecing together of dissociated documentation and best practices, with a few touch-ups of my own. The end goal is a distilled, yet hopefully comprehensive…

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Ansible & fork (un)safety

Running a simple, single-task playbook on macOS 10.15 returned this error: Turns out macOS 10.13 onward started enforcing stricter rules on -safety. To get the older, unsafe behaviour (temporarily) back, use this environment variable: Here's a detailed writeup on this, with a focus on Ruby servers.

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pgTAP's case-sensitivity

The following pgTAP inconsistency led to a few wasted hours. Turns out that handles both upper- and lower-case input for its parameter, whereas only handles the lower-case version. Case in point, given this function ... ... the first test passes, while the second one fails with the error! At…

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Automated permissions testing

Previously we've covered deeplinks with automated tests. Let's now do the same for permissions. We'll only showcase doing so for notifications, but the same would apply to others: camera, photos, location, calendar, reminders, microphone, etc. UI testing power-up First we need to empower UI testing…

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Automated deeplinks testing

UI testing under iOS 11 has the ability to interact with other installed apps. Specifically, got a new constructor that takes a bundle ID. Let's see how we use this to put our deeplinks under automated tests. Overview What you basically do is create a helper-app, in below examples, that merely…

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Stanford CS229

Just finished Andrew Ng's ML course and I can wholeheartedly recommend it as a nice balance of both exposition and hands-on work. Was a bit surprised though when, around logistic regression, maybe thirdway through the course, prof. Ng said that in his experience of "walking around Silicon Valley…

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One weird trick

One weird Swift trick to not have to come up with silly and inconsistent names for the unwrapped : Fellow developers might hate you for doing this, for it is a Swift compiler bug. Swift does allow backticks to use a otherwise reserved word in other cases though. Update: This has been fixed in Swift…

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Boy scout rule

A good boy scout "leaves the campground cleaner than he found it". Or at least, not leave the campground messier than he found it. In iOS this includes those 'misplaced views' warnings that Xcode sometimes unhelpfully causes, when you merely peek at files. Future Xcode releases will hopefully fix…

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Accurate iOS code coverage

The natural next step from testing your code, perhaps even in a test-first manner, is knowing how much of your code is covered by these tests. To do that, you have to first open the and tell Xcode to . Running unit tests as is would give you inaccurate coverage, as it would take into account and…

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Automate Xcode upgrades

It seems unavoidable for new Xcode versions to override any custom keybindings. Ditto for a custom, brighter text-cursor, which is pretty much a necessity when using a darker background. And let's not forget the plugins. Since Xcode updates aren't that rare, here is a script of all the steps: Xcode…

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