ACCU World of Code

On my phone and computer I use WhatsApp, Signal, Slack, Keybase, Discord, IRC, XMPP/Jabber and Element/Matrix. In addition, I occasionally use the messaging features of Mastodon, Twitter and even LinkedIn. I’ve never used Telegram, Line, WeChat, Sessio…

This was quite a challenge, and I nearly gave up, but I managed to write a Snake game in Terraform: Slides: artificialworlds.net/presentations/snake-terraform Source code: gitlab.com/andybalaam/snake Slides source code: gitlab.com/andybalaam/videos-sn…

I have recently started using Kupfer again as my application launcher in Ubuntu MATE, and I found it lacked the ability to suspend the computer. Here is the plugin I wrote to support this. To install it, quit Kupfer, create a directory in your home dir…

PeerTube’s API documentation gives an example of how to upload a video, but it is missing a couple of important aspects, most notably how to provide multiple tags use form-encoded input, so my more complete script is below. Use it like this: # First, m…

Being fed up with the limited configurability of some of the more widely used software used for video conferencig, I have put together a small LD_PRELOAD-able shared library that limits the available resolutions a webcam reports. Have a look at the REA…

Being fed up with the limited configurability of some of the more widely used software used for video conferencig, I have put together a small LD_PRELOAD-able shared library that limits the available resolutions a webcam reports. Have a look at the REA…

Category Theory is an incredibly exciting and challenging area of Maths, that (among other things) can really help us understand what programming is on a fundamental level, and make us better programmers. By far the best explanation of Category Theory…

Visual Lint 8.0.1.337 is a recommended maintenance update for Visual Lint 8.0. The following changes are included: If the Visual Studio plugin is selected for installation and the Visual Studio Debug Console (VsDebugConsole.exe) is running, the insta…

Visual Lint 8.0.1.337 is a recommended maintenance update for Visual Lint 8.0. The following changes are included: If the Visual Studio plugin is selected for installation and the Visual Studio Debug Console (VsDebugConsole.exe) is running, the insta…

It’s hard to believe it’s already a year since the release of RFC 8771 (The Internationalized Deliberately Unreadable Network NOtation), which for me at least made me think about IP addresses in a whole new way. So, it seems fitting for the anniversary…

Lots of people are filling in the extremely detailed UK government COVID test result page twice every week. It asks you to fill in a very large list of details, most of which are the same every time, but it doesn’t remember what you typed last time. I …

The first public build of Visual Lint 8.0 has just been uploaded to our website. As of today, Visual Lint 8.0 replaces Visual Lint 7.0 as the current supported Visual Lint version. As such Visual Lint 8.0 licences (as well as upgrades for Visual Lint 6…

The first public build of Visual Lint 8.0 has just been uploaded to our website. As of today, Visual Lint 8.0 replaces Visual Lint 7.0 as the current supported Visual Lint version. As such Visual Lint 8.0 licences (as well as upgrades for Visual Lint 6…

The Internet is full of outdated Python code for doing things with windows, so here is what I got working today in a Python 3, GTK 3 environment. This script toggles the window decorations on the active window on and off. I have it bound to Ctrl+NumPad…

During my work on RFC 8771 The Internationalized Deliberately Unreadable Network NOtation (I-DUNNO) I have come across a number of questions. I am documenting them here so I can send them to the authors and try to improve my understanding of the intent…

At the ACCU Conference last week I learned about RFC 8771 The Internationalized Deliberately Unreadable Network NOtation (I-DUNNO) from Jim Hague, and thought it would be fun to knock up a Rust implementation. The project is here: gitlab.com/andybalaam…

Sent via WriteToThem on Monday 1 March 2021. Dear Ben Spencer, Your experience on the front line in medicine means you are probably much more able than I to imagine the human impact of the situation in Yemen. On Sunday OCHA stated that 16 million peopl…

We’ve all done it. You prepare a new build, install it, start testing before releasing it and then…it crashes. The immediate thought is always “What have we done…?”. Exactly that happened to us recently when testing a Visual Lint build – all we did…

We’ve all done it. You prepare a new build, install it, start testing before releasing it and then…it crashes. The immediate thought is always “What have we done…?”. Exactly that happened to us recently when testing a Visual Lint build – all we did…

I’ve added the first features intended to make Smolpxl games work well on touch interfaces like phones and tablets: I’ve added a button bar at the bottom (and moved the navigation buttons to the top). I’m looking for feedback on this: Does it work on…

I learned quite a bit today about how to think about concurrency in Rust. I was trying to use a Semaphore to limit how many open sockets my TCP listener allowed, and I had real trouble making it work. It either didn’t actually work, allowing any number…

Here is the email I just sent to the organisation I volunteer for. Feel free to adapt and use in your context. Dear [organisation leaders], Much of the tech industry (e.g. [1]) is warning against the use of WhatsApp due to its policy of collecting and …

I just streamed about 40 minutes of me playing Trials Fusion using Owncast. Owncast is a self-hosted alternative to streaming services like Twitch and YouTube live. Normally, you would need to pay for a computer to self-host it on. Owncast suggest this…

I got a Pinephone for Christmas! Here is quick summary of my experience with it. (Originally published on mastodon.) Update on the pinephone as promised. I love it, but I would definitely not recommend expecting to use it as your actual phone. I have …

Maybe everyone knows this already, but for my own clarity, I think there are really two types of computer program: A function: something that you run, and get back a result. Example: a command-line tool like ls A service: something that sits around wa…

Some Java code with bugs Here’s my main method (in Java). Can you guess the bug? Db db = new Db(); Monitoring monitoring = new Monitoring(); Monitoring mon2 = new Monitoring(); Billing billing = new Billing(db, monitoring); monitoring.setDb(db); runMa…

I’m looking into Edge computing at work. By Edge computing I mean running WASM programs in lots and lots of smallish computers in places near to actual people (rather than in huge cloud data centres). I think it’s cool because I love Rust, and Rust is …

Are you writing schema upgrade code? Then I humbly suggest you take the time to write schema downgrade code too. “Why would I do that?” you might well ask, “I won’t ever need to downgrade.” Now, I imagine you’re expecting me to say you actually will ne…

You can make levels for Rabbit Escape!

It’s a very early beta for now, but I’m ready to announce Smolpxl Scores, which provides high-score tables for Free and Open Source games. Each game can have multiple high-score tables – for example, you might want one for each level. At the moment it’…

I upgraded to Ubuntu 20.04.1 and chose to keep my existing config files, and my mail server stopped working. In the log I saw: Nov 25 09:07:57 machine dovecot: imap-login: Error: Failed to initialize SSL server context: Can’t load DH parameters: error:…

Letter I sent to my MP today on the overseas aid budget. Let’s not be foolish. Dear Ben Spencer, Please use your influence to persuade the government to maintain our overseas aid budget commitment at 0.7% of national income. I believe that changing th…

I have a unit test that is running slowly, and I want a quick view of what is happening. I can get a nice overview of where the code spends its time by adding this to the JVM arguments: -agentlib:hprof=cpu=samples,lineno=y,depth=3,file=hprof.samples.tx…

is an excellent book by Carlo Rovelli (isbn 978-0-141-98321-9) As usual I’m going to quote from a few pages. It doesn’t describe where there is a particle but how the particle shows itself to others. It isn’t things that enter into relations…

is an excellent book by Carlo Rovelli (isbn 978-0-141-98321-9) As usual I’m going to quote from a few pages. It doesn’t describe where there is a particle but how the particle shows itself to others. It isn’t things that enter into relations…

Recently I’ve been having a lot of fun working on Smolpxl, which is a web site featuring some little retro web games that are all Free and Open Source Software. Here’s a sneak preview of the game I am working on: Why do this? Apart from the fact that …

Dear Anneliese Dodds MP,  I have voted for you in the last two elections, as a proxy for my support for Jeremy Corbyn, though your attendance and performance at the hustings arranged by the Stop the War Coalition was a reason for my suppor…

is an excellent book by Jacob Bronowski (isbn 0-7088-2035-2) As usual I’m going to quote from a few pages. Evolution is the climbing of a ladder from the simple to the complex by steps, each of which is stable in itself. The turning point to…

is an excellent book by Jacob Bronowski (isbn 0-7088-2035-2) As usual I’m going to quote from a few pages. Evolution is the climbing of a ladder from the simple to the complex by steps, each of which is stable in itself. The turning point to…

is an excellent book by Paul Nurse (isbn 978-1-788451-40-6) As usual I’m going to quote from a few pages. Cells repair these mutations, but they are not completely successful. If they were, all individuals of a species would be identical and evo…

is an excellent book by Paul Nurse (isbn 978-1-788451-40-6) As usual I’m going to quote from a few pages. Cells repair these mutations, but they are not completely successful. If they were, all individuals of a species would be identical and evo…

Welcome! We are going to code a whole snake game. It’s going to look like this: It doesn’t matter if you have never written any code before: I am going to try and explain everything from scratch. I’m going to assume you are using a Raspberry Pi. but y…

is an excellent book by Yuval Noah Harari (isbn 978-0-099-59008-8) As usual I’m going to quote from a few pages. Whereas chimpanzees spend five hours a day chewing raw food, a single hour suffices for people eating cooked food. Since long inte…

is an excellent book by Yuval Noah Harari (isbn 978-0-099-59008-8) As usual I’m going to quote from a few pages. Whereas chimpanzees spend five hours a day chewing raw food, a single hour suffices for people eating cooked food. Since long inte…

is an excellent book by Daniel Coyle (isbn 978-1-847-94127-5) As usual I’m going to quote from a few pages. Much of the connection happens around the dinner table, as Popovich is obsessed with food and wine. One misconception about highly succ…

is an excellent book by Daniel Coyle (isbn 978-1-847-94127-5) As usual I’m going to quote from a few pages. Much of the connection happens around the dinner table, as Popovich is obsessed with food and wine. One misconception about highly succ…

I love simple games: playing them and writing them. But, it can be overwhelming getting started in the complex ecosystems of modern technology. So, I am writing the Smolpxl library, which is some JavaScript code that makes it quite simple to write simp…

I was looking for the right way to make a “Share This”-style button for my tiny games site Smolpxl, and I found shareon which worked exactly the way I wanted (load the JavaScript and call a function to display the buttons, with no privacy concerns), an…

I’m working on a little JavaScript library called Smolpxl. It aims to make it really easy to create retro-style pixellated games that run well in the browser, using simple JavaScript. This is me live-streaming writing a tiny “game” using Smolpxl: To …

Sometimes I run grep commands that search files with hugely-long lines. If those lines match, they are printed out and spam my terminal with huge amounts of information, that I probably don’t need. I couldn’t find a tool that limits the line-length of …

 The word “algorithm” has caused a storm in recent news in the UK. Due to COVID-19 school children were not able to sit their exams. This left 16 and 18 year olds waiting to see how they would be assessed, and had obvious implications for their ac…

 The word “algorithm” has caused a storm in recent news in the UK. Due to COVID-19 school children were not able to sit their exams. This left 16 and 18 year olds waiting to see how they would be assessed, and had obvious implications for their ac…

To set the date when a photo was taken, install ExifTool e.g.: sudo apt install libimage-exiftool-perl # If on Ubuntu sudo dnf install perl-Image-ExifTool.noarch # If on Fedora And modify the photo with a command like this: exiftool -DateTimeOrigina…

SMPP is a binary protocol used by phone companies to send text messages, otherwise known as SMS messages. It can work over TCP, so we can use netcat on the command line to send messages. A much better way to understand this protocol is to use Wireshark…

Here is the text of a letter I wrote to my MP today via writetothem.com: Dear [], I am writing to you to express my growing horror at the ongoing police violence and brutality Black protesters are facing in the US, and the UK’s disturbing silence on t…

If there is any single consolation amidst the circumstances we are all having to cope with at the moment it is that many of us have lots of time to fill – not only with unproductive things like binging Netflix (I really should get around to watching Di…

If there is any single consolation amidst the circumstances we are all having to cope with at the moment it is that many of us have lots of time to fill – not only with unproductive things like binging Netflix (I really should get around to watching Di…

My grandfather, Norman Angier, worked at Churchill’s Toyshop (M.D.1) as the head civilian engineer during WWII. On VE day “Norman Angier felt it was an occasion for fireworks. He therefore acquired a large batch of quite big rockets and proc…

My grandfather, Norman Angier, worked at Churchill’s Toyshop (M.D.1) as the head civilian engineer during WWII. On VE day “Norman Angier felt it was an occasion for fireworks. He therefore acquired a large batch of quite big rockets and proc…

I’ve spent the last couple of days fighting the Android command line to set up a simple project that can run automated tests inside an emulator reliably and repeatably. To make the tests reliable and independent from anything else on my machine, I want…

Made some significant progress for running Tizen on an Orange Pi PC (and hopefully any other SBC with a similar Mali GPU). Main issue was that alignments in TBM (Tizen Buffer Manager) weren’t in sync with what the actual GPU driver expected. With that …

Made some significant progress for running Tizen on an Orange Pi PC (and hopefully any other SBC with a similar Mali GPU). Main issue was that alignments in TBM (Tizen Buffer Manager) weren’t in sync with what the actual GPU driver expected. With that …

I am building a toy project in Rust to help me learn how to deploy things in AWS. I’m considering using Elastic Beanstalk (AWS’s platform-as-a-service) and also Kubernetes. Both of these support deploying via Docker containers, so I am learning how to …

While trying to get Tizen working on my Orange Pi PC, I noticed some strange behaviour in the Linux kernel in that SIGCHLD signals sent to the parent process don’t always set the “si_pid” field correctly. I tracked this down to a bug in the Linux kerne…

While trying to get Tizen working on my Orange Pi PC, I noticed some strange behaviour in the Linux kernel in that SIGCHLD signals sent to the parent process don’t always set the “si_pid” field correctly. I tracked this down to a bug in the Linux kerne…

A corner of the roof of our office building. Even though the sea is just over 350m away to the left, sadly it’s currently off-limits. 2020 is not turning out to be what we expect as – like much of the world – the UK is locked down right now as a resul…

A corner of the roof of our office building. Even though the sea is just over 350m away to the left, sadly it’s currently off-limits. 2020 is not turning out to be what we expect as – like much of the world – the UK is locked down right now as a resul…

is an excellent book by Douglas Adams (isbn 978-0-330-49120-4). As usual I’m going to quote from a few pages. He would insult the universe. That is, he would insult everybody in it. Individually, personally, one by one, and (this was the thing t…

is an excellent book by Douglas Adams (isbn 978-0-330-49120-4). As usual I’m going to quote from a few pages. He would insult the universe. That is, he would insult everybody in it. Individually, personally, one by one, and (this was the thing t…

I was recording some podcast audio tonight and wanted to be able to press a single key when I reached a significant moment, so I could add the times to the show notes. I couldn’t find anything that already did this, so I wrote a tiny bash script. I ran…

is an excellent book by Douglas Adams (isbn 978-0-330-49121-1). As usual I’m going to quote from a few pages. There is another theory which states that this has already happened. The story so far: In the beginning the Universe was created. Thi…

is an excellent book by Douglas Adams (isbn 978-0-330-49121-1). As usual I’m going to quote from a few pages. There is another theory which states that this has already happened. The story so far: In the beginning the Universe was created. Thi…

I previously wrote an overview showing how decision trees work: http://buontempoconsulting.blogspot.com/2019/07/decision-trees-for-feature-selection.html This time, let’s build a decision tree with some data. There are many freely available data …

I previously wrote an overview showing how decision trees work: http://buontempoconsulting.blogspot.com/2019/07/decision-trees-for-feature-selection.html This time, let’s build a decision tree with some data. There are many freely available data …

is an excellent book by Douglas Adams (isbn 978-0-330-49119-8). As usual I’m going to quote from a few pages. Far out in the uncharted backwaters of the unfashionable end of the Western Spiral Arm of the Galaxy lies a small unregarded yellow sun…

is an excellent book by Douglas Adams (isbn 978-0-330-49119-8). As usual I’m going to quote from a few pages. Far out in the uncharted backwaters of the unfashionable end of the Western Spiral Arm of the Galaxy lies a small unregarded yellow sun…

I love Bash tab completion, and I want it for the command I am writing, so it can automatically complete parts of the command line when I run my program. Code Here is the script (install-bash-completion) I wrote to set it up (no need to be root – it in…

I am loving writing code in Rust. So many things about the language and its ecosystem feel so right*. * For example: ownership of objects, expressive type system, compile to native, offline API docs, immutability, high quality libraries. One of the thi…

Got a $20 voucher code for a review of a Rock Pi S SBC. Although the cost of the board is only $13.90, with shipping at just over $8, it’s a bit over $22 in total. When the board arrived, I did actually wonder if shipping could have been made a bit mor…

Got a $20 voucher code for a review of a Rock Pi S SBC. Although the cost of the board is only $13.90, with shipping at just over $8, it’s a bit over $22 in total. When the board arrived, I did actually wonder if shipping could have been made a bit mor…

I tried to describe the main ideas that will help you write decent React code. Maybe it will help you understand the docs a bit more when you read them… Slides: React Concepts slides