Table subset searching with a list and DBIx::Class
When searching for a subset of rows in a database table by using a list of entries in one of its columns, one can use the WHERE column_name IN list syntax in...
Posts by Year
2024
Book review: A Common-Sense Guide to Data Structures and Algorithms
A Common-Sense Guide to Data Structures and Algorithms (second edition) by Jay Wengrow is a clearly explained and (dare I say it) fun guide to data structure...
A dinosaur learns poetry
Not a real dinosaur and not real poetry. Just me updating my Python project setup knowledge.
Resizing the disk on a Vagrant virtual machine
When creating a Vagrant VM, one gets a pre-determined VM disk size. While this is more than enough in most use cases, sometimes it isn’t enough for what one...
Avoiding Ansible apt_key on Debian
The apt_key Ansible module has been deprecated and there isn’t a drop-in replacement. There is a workaround available which achieves the same result but req...
The Enterprise amusement park ride
As part of tutoring physics and maths to high school students, I sometimes write up deep-dive explanations of questions arising during lessons. Below I disc...
Book review: Practical Object-Oriented Design
Practical Object-Oriented Design by Sandi Metz: A well-paced, well-structured, and well-written introduction to the concepts of object-oriented design.
Using a Garmin Edge 530 head unit with Linux
As a Linux user, getting commodity devices like GPS head units to play nicely can be hard. This is why I was particularly happy to find out that Garmin devi...
Fixing a fifteen-year-old curve fit bug
The backwards compatibility of Perl software is wonderful. That’s why it’s all the more jarring when you find a package that doesn’t work. This is the stor...
Resurrecting tmux sessions after restart
Have you ever wished your tmux sessions could magically spring back to life after having had to restart your computer? With tmux-resurrect, they can.
Car crash calculation counsel
A trip to the library ended up being more eventful and instructive than planned. This is the story of how a bit of physics led me to look deeper into a car ...
Test that forking code!
Not only should the final commit in a pull request patch series pass all its tests but also each commit back to where the pull request branched from main. A...
Throwing a javelin and finding where it lands
As part of tutoring physics and maths to high school students, I sometimes write up deep-dive explanations of questions arising during lessons. Below I disc...
Adding Shields.io badges to your GitHub profile
A GitHub user profile page can be a great place to show off what you’re interested in and what experience you might have. Rather than presenting a wall of t...
Basic Python project setup
Setting up an existing Python project from a fresh clone shouldn’t be a chore. Automate the process with a setup script.
Unnecessary upload evasion with lftp mirrors
I’ve been using lftp’s reverse mirror feature for years to upload files to this blog. I’d never worked out how to avoid repeated file uploads. Until now.
Evaporating a pot of water
As part of tutoring physics and maths to high school students, I sometimes write up deep-dive explanations of questions arising during lessons. The question...
Correcting iBus/X-Windows compose key conflicts
Did you know that iBus can cause the compose key to stop working in X-Windows on Linux? I didn’t either. The solution in my situation: if in doubt, leave i...
Breaking spaces in vim
Some text editing software packages seem to insert non-breaking spaces into files willy-nilly. This can be a pain if you don’t want them. Also, they’re ver...
Better date mocking in Python tests with FreezeGun
A couple of years ago I stumbled across the FreezeGun library. It’s been a great help in making the date/time-related intent in my Python tests much clearer....
Avoiding stringy eval in Perl
Once upon a time, I used to take an active part in the CPAN Pull Request Challenge (and later in the Pull Request Club). One task I tackled as part of each ...
German Perl/Raku Workshop Frankfurt 2024
This week I was at the German Perl/Raku Workshop in Frankfurt. This is the main yearly meetup of the German-speaking Perl/Raku community. The event isn’t j...
Sailplane glide distance
As part of tutoring physics and maths to high school students, I sometimes write up deep-dive explanations of questions arising during lessons. The question...
Starting ssh-agent in Windows PowerShell
As someone who works mostly on Linux, there seem to be a multitude of issues for me to stumble over when having to use Windows. Using ssh in Windows PowerSh...
Letting mere mortals run Windows PowerShell scripts
While playing with Raku and rakubrew on Windows recently, I encountered more than one stumbling block. One stuck out in particular. Did you know that, by def...
Building and testing Raku in AppVeyor
Trying to get an old Raku project up and running again led me down a deep rabbit hole. I ended up working out how to set up, build, and test Raku projects on...
Hotel hotspot hijinks
Ever been staying at a hotel and gotten annoyed that you always have to open a browser to log in for wireless access? Yup, me too. A recent instance was pa...
2023
ptc-it.de is now peateasea.de
It’s been annoying me for a while now that the URL for this blog somehow just didn’t sound nice. I finally came up with a better-sounding domain name and ha...
Bash-ing our way to a project’s base directory
Do you want your script to be told where it needs to run? Or would you rather it work things out for itself? Personally, I find the more a script can work ...
German Perl/Raku Workshop Frankfurt 2023
It was that time of the year again: late winter/early spring; time for the German Perl/Raku Workshop. This year (2023) it was held in Frankfurt and thus hos...
Vim hjkl arrow keys T-shirt design
Back in 2018 I found a T-shirt featuring vim’s hjkl arrow keys but stocks were sold out. I therefore had a dab at designing my own.
Reverting migrations in Django
When developing Django applications it’s sometimes necessary to revert (i.e. undo) a migration, especially if something didn’t quite work as planned. If som...
2022
Rewriting author information in Git commits
Ever needed to change your email address in your Git history? For instance, you’ve mistakenly used your personal email address in a repository at work? Here...
The curious case of the disappearing PDF text
A case of disappearing text in an auto-generated PDF document led me to dig deeper and learn more about ReportLab: a PDF generation library. Here’s the stor...
Adventures in collating text in Linux, Docker and Postgres
It’s interesting how bugs can lead to a deeper understanding of how computer systems work. It’s also amazing how nuanced some technical topics can be. For i...
Installation, setup and basic use of the SourceTree Git client
Recently I’ve been investing more time in documentation at work to try and make it easier for new staff members to come up to speed. The following HOWTO has...
Migrating project management software from Redmine to GitLab
Migrating tickets, comments, roadmaps and wiki pages from Redmine to GitLab is a lot of work if you do it by hand. Fortunately, one can automate this proces...
Tunneling through a gateway server via SSH
Some of the servers I manage are hidden behind a corporate firewall and hence not accessible from the open internet. In order to access them from my office ...
Headless Cordova Android builds on Jenkins
This is a fairly old story, nevertheless I still think it’s worthwhile telling, just in case someone else wants to build Android APKs from Cordova within the...
German Perl/Raku Workshop Leipzig 2022
The workshop was held only online last year due to the pandemic, thus it was really nice to be able to see people in-person again (my first workshop/conferen...
2021
Pull Request Club October 2021: App::ConsistentRandomPassword
This month, as part of the Pull Request Club, I was assigned the Perl distribution App::ConsistentRandomPassword. This is my report of what I found out about...
Agile Testing Days 2021
This is the first in-person conference for me in almost two years. Crazy times! Below are my notes from the talks that I attended at the Agile Testing Days...
Weaning my website off cookies
Do you find having to accept or decline cookies everywhere on the web annoying? Me too. That’s why I decided to remove cookies from this blog. Here’s how I...
Pull Request Club: April 2021
The Pull Request Club is a way to connect open source maintainers to contributors through monthly assignments. It’s free to join up (just use your GitHub lo...
2020
Adding a favicon to a Jekyll-based static website
Having a favicon on your website can be a nice touch, especially if you’ve got a cool logo. Unfortunately, I don’t have a cool logo, however I thought I’d a...
Two handy mutt tips
Mutt is a very powerful email client, mainly because it’s terminal-based and because it has a vast array of terse commands reminiscent of the terse command p...
Setting up Jenkins email sender configuration correctly
To set up the configuration for sending email on Jenkins correctly, it’s necessary to set options in two quite separate locations within the main Jenkins con...
Backing up photos from Android to Debian
One would think that since Android is a Linux-based operating system, that integration between Android devices and Linux computers would work rather seamless...
Working around the focus-click problem in Selenium
Sometimes Selenium can lose browser focus when running tests, which can cause timeout errors when testing click events in a web application. Here I discuss ...
Enabling cookie consent on a Jekyll Minimal Mistakes site
It turns out that my Jekyll-based static site was storing cookies, of which I wasn’t aware. Oops! Sorry! Cookie opt-in is required by law in Germany and I...
Creating a random secret key in Raku
This post might seem a bit silly, because I’ve already posted this tip on Twitter about a year ago. Nevertheless, I needed exactly this piece of information...
Relative copy and paste in vim
Sometimes there seems to be so much hidden power in vim that it’s just stunning. It’s like there’s a hidden reservoir of power just underneath the surface o...
Book review: Technical blogging; second edition
Technical blogging, second edition by Antonio Cangiano is–as the title implies–a book about blogging for the technically inclined. It guides the reader from...
Developing an OpenLayers app from scratch in ES6 using Mocha, Webpack and Karma: Arctic sea-ice data visualisation
… where we finally visualise actual sea-ice concentration data and migrate our tests to karma.
Developing an OpenLayers app from scratch in ES6 using Mocha, Webpack and Karma: Projections
… where we investigate projections and view our map from an Arctic perspective.
Developing an OpenLayers app from scratch in ES6 using Mocha, Webpack and Karma: Mocha tests
… where we start testing our application.
Developing an OpenLayers app from scratch in ES6 using Mocha, Webpack and Karma: Initial app
… where we create a simple OpenLayers map and modularise our code for later use.
Developing an OpenLayers app from scratch in ES6 using Mocha, Webpack and Karma
It looks a bit like I’m trying some kind of SEO trick with this title. Believe me, I’m not! It’s just amazing how many technologies were necessary to get in...
2019
Moving Files and Directories to a New Repository in Git
I’ve needed to move files or directories (along with their histories) from one Git repository into a new repository often enough now that I’m annoyed with my...
ssh, tmux and vim: A Simple Yet Effective Pair Programming Setup
At my work, Drift+Noise, we try to use Agile software development methods where possible. For instance, we use TDD largely for our unit tests, BDD for funct...
Automating Use of the PostGIS Backend for Django Tests
Ever had the problem that your automated Django tests wouldn’t work because you didn’t have permissions to create the given extension and you thought: “WTF? ...
Fixing ‘cache resources exhausted’ errors in imview
imview is a handy image viewing application for Linux. I’ve started using this at $work recently, because Eye of Gnome, a.k.a eog, (my usual go-to applicati...
Installing Android Studio for Apache Cordova
At work we’re looking at using Apache Cordova to create cross-platform applications. The idea of being able to use a single code base and yet still target A...
The Trick with Perl6 and Linux: Staying Composed
During Andrew Shitov’s talk about Perl6 one-liners at the recent German Perl Workshop in Munich I followed along on the Perl6 REPL trying out the examples as...
2017
Helping to clean CPAN: January 2017
… where I get out my virtual broom and sweep up cruft I can find in my assigned distribution for this month’s edition of the CPAN Pull Request Challenge.
2016
Helping to clean CPAN: December 2016
… where I get out my virtual broom and sweep up cruft I can find in my assigned distribution for this month’s edition of the CPAN Pull Request Challenge.
Helping to clean CPAN: November 2016
… where I get out my virtual broom and sweep up cruft I can find in my assigned distribution for this month’s edition of the CPAN Pull Request Challenge.
Controlling screen brightness via ACPI
Really, this is just a workaround for an issue I haven’t completely understood. Nevertheless, since I had to work out how I’d handled brightness control via...
Helping to clean CPAN: October 2016
… where I get out my virtual broom and sweep up cruft in my assigned distribution for this month’s edition of the CPAN Pull Request Challenge.
Helping to clean CPAN: September 2016
… where I get out my virtual broom and sweep up cruft in my assigned distribution for this month’s edition of the CPAN Pull Request Challenge.
Helping to clean CPAN: August 2016
… where I get out my virtual broom and sweep up cruft in my assigned distribution for this month’s edition of the CPAN Pull Request Challenge.
YAPC::EU 2016 Day 3
These are my notes from the talks I attended at the third day of YAPC::EU 2016.
Building Rakudo the hard way
One can build Rakudo very easily via rakudobrew, for instance:
YAPC::EU 2016 Day 2
These are my notes from the talks I attended at the second day of YAPC::EU 2016.
YAPC::EU 2016 Day 1
These are my notes from the talks I attended at the first day of YAPC::EU 2016.
Helping to clean CPAN: July 2016
… where I get out my virtual broom and sweep up cruft in my assigned distribution for this month’s edition of the CPAN Pull Request Challenge.
Helping to clean CPAN: June 2016
… where I get out my virtual broom and sweep up cruft in my assigned distribution for this month’s edition of the CPAN Pull Request Challenge.
Helping to clean CPAN: May 2016
… where I get out my virtual broom and sweep up cruft in my assigned distribution for this month’s edition of the CPAN Pull Request Challenge.
Helping to clean CPAN: April 2016
… where I get out my virtual broom and sweep up cruft in my assigned distribution for this month’s edition of the CPAN Pull Request Challenge.
NPLW 2016
The Dutch Perl Workshop (NLPW) was held on the 1st of April, 2016. Many jokes were made about the date being no joke… Here are some of my impressions about...
Helping to clean CPAN: March 2016
… where I get out my virtual broom and sweep up cruft in my assigned distribution for this month’s edition of the CPAN Pull Request Challenge.
Helping to clean CPAN: February 2016
… where I get out my virtual broom and sweep up cruft in my assigned distribution for this month’s edition of the CPAN Pull Request Challenge.
Helping to clean CPAN: January 2016
… where I get out my virtual broom and sweep up cruft in my assigned distribution for this month’s edition of the CPAN Pull Request Challenge.
2015
Helping to clean CPAN: December 2015
… where I get out my virtual broom and sweep up cruft in my assigned distribution for this month’s edition of the CPAN Pull Request Challenge.
Helping to clean CPAN: November 2015
… where I get out my virtual broom and sweep up cruft in my assigned distribution for this month’s edition of the CPAN Pull Request Challenge.
Helping to clean CPAN: October 2015
… where I get out my virtual broom and sweep up cruft I can find in my assigned distribution for this month’s edition of the CPAN Pull Request Challenge.
Processing files with spaces in filenames
Sometimes I get files from friends who use certain graphical operating systems, where it’s ok to use spaces in filenames. Processing these files on Unix isn...
Perl 6 hackathon at the Swiss Perl Workshop
The third instalment of the Swiss Perl Workshop will take place in the last week of August 2015. Part of the workshop will be a Perl 6 Hackathon, one of the...
Cleaning the CPAN cage: January 2015
In the first installment of my participation in the CPAN Pull Request Challenge I was assigned the module XML::NamespaceSupport. The module enables one to pr...
Module clean up ideas for the CPAN Pull Request Challenge
At the end of 2014 I signed up for the CPAN Pull Request Challenge; a brilliant idea of Neil Bower’s to clean up CPAN modules in need of a bit of “tender lov...
2014
Windows Git Installation
A version control system is fundamental to the work of anyone developing software, whether it be scientific software or not. This is one of the fundamental ...
Test suite profiling
Recently at $work I found that our test suite was taking longer and longer to run and had begun to slow down development. A long-running test suite smells of...