Author: Jenny List

3267 Articles

Track Your GitHub Activity With This E-Ink Display

July 5, 2025 by 5 Comments

If you’re a regular GitHub user you’ll be familiar with the website’s graphical calendar display of activity as a grid. For some of you it will show a hive of activity, while for others it will be a bit spotty. If you’re proud of your graph though, you’ll want to show it off to the world, and that’s where [HarryHighPants]’ Git Contributions E-Ink Display comes in. It’s a small desktop appliance with a persistent display, that shows the current version of your GitHub graph.

At its heart is an all-in-one board with the display and an ESP32 on the back, with a small Li-Po cell. It’s all put in a smart 3D printed case. The software is the real trick, with a handy web interface from which you can configure your GitHub details.

It’s a simple enough project, but it joins a growing collection which use an ESP32 as a static information display. The chip is capable of more though, as shown by this much more configurable device.

It’s 2025, And We Still Need IPv4! What Happens When We Lose It?

July 3, 2025 by 79 Comments

Some time last year, a weird thing happened in the hackerspace where this is being written. The Internet was up, and was blisteringly fast as always, but only a few websites worked. What was up? Fortunately with more than one high-end networking specialist on hand it was quickly established that we had a problem with our gateway’s handling of IPv4 addresses, and normal service was restored. But what happens if you’re not a hackerspace with access to the dodgy piece of infrastructure and you’re left with only IPv6? [James McMurray] had this happen, and has written up how he fixed it.

His answer came in using a Wireguard tunnel to his VPS, and NAT mapping the IPv4 space into a section of IPv6 space. The write-up goes into extensive detail on the process should you need to follow his example, but for us there’s perhaps more interest in why here in 2025, the loss of IPv4 is still something that comes with the loss of half the Internet. As of this writing, that even includes Hackaday itself. If we had the magic means to talk to ourselves from a couple of decades ago our younger selves would probably be shocked by this.

Perhaps the answer lies in the inescapable conclusion that IPv6 answers an address space problem of concern to many in technical spaces, it neither solves anything of concern to most internet users, nor is worth the switch for so much infrastructure when mitigations such as NAT make the IPv4 address space problem less of a problem. Will we ever entirely lose IP4? We’d appreciate your views in the comments. For readers anxious for more it’s something we looked at last year.

Finally, An Extension To Copyright Law We Can Get Behind

July 2, 2025 by 31 Comments

Normally when a government extends a piece of copyright law we expect it to be in the favour of commercial interests with deep pockets and little care for their consumers. But in Denmark they do things differently it seems, which is why they are giving Danes the copyright over their own features such as their faces or voices. Why? To combat deepfakes, meaning that if you deepfake a Dane, they can come after you for big bucks, or indeed kronor. It’s a major win, in privacy terms.

You might of course ask, whether it’s now risky to photograph a Dane. We are not of course lawyers here but like any journalists we have to possess a knowledge of how copyright works, and we are guessing that the idea in play here is that of passing off. If you take a photograph of a Volkswagen you will have captured the VW logo on its front, but the car company will not sue you because you are not passing off something that’s not a Volkswagen as the real thing. So it will be with Danes; if you take a picture of their now-copyrighted face in a crowd you are not passing it off as anything but a real picture of them, so we think you should be safe.

We welcome this move, and wish other countries would follow suit.

Pope Francis, Midjourney, Public domain, (Which is a copyright story all of its own!)

Chasing A Raspberry Pi Bottleneck

June 30, 2025 by 9 Comments

The Raspberry Pi has been used for many things over its lifetime, and we’re guessing that many of you will have one in perhaps its most common configuration, as a small server. [Thibault] has a Pi 4 in this role, and it’s used to back up the data from his VPS in a data centre. The Pi 4 may be small and relatively affordable, but it’s no slouch in computing terms, so he was extremely surprised to see it showing a transfer speed in bytes per second rather than kilobytes or megabytes. What was up? He set out to find the bottleneck.

We’re treated to a methodical step-through of all the constituent parts of the infrastructure between the data centre and the disk, and all of them show the speeds expected. Eventually, the focus shifts to the encryption he’s using, both on the USB disk connected to the Pi and within the backup program he’s using. As it turns out, while the Pi is good at many things, encryption is not its strong point. Some work with htop shows the cores maxed out as it tries to work with encrypted data, and he’s found the bottleneck.

To show just how useful a Pi server can be without the encryption, we’re using an early model to crunch a massive language corpus.

Header image: macrophile, CC BY 2.0.

Break The Air Gap With Ultrasound

June 29, 2025 by 15 Comments

In the world of information security, much thought goes into ensuring that no information can leave computer networks without expressly being permitted to do so. Conversely, a lot of effort is expended on the part of would-be attackers to break through whatever layers are present. [Halcy] has a way to share data between computers, whether they are networked or not, and it uses ultrasound.

To be fair, this is more of a fun toy than an elite exploit, because it involves a web interface that encodes text as ultrasonic frequency shift keying. Your computer speakers and microphone can handle it, but it’s way above the human hearing range. Testing it here, we were able to send text mostly without errors over a short distance, but at least on this laptop, we wouldn’t call it reliable.

We doubt that many sensitive servers have a sound card and speakers installed where you can overhear them, but by contrast, there are doubtless many laptops containing valuable information, so we could imagine it as a possible attack vector. The code is on the linked page, should you be interested, and if you want more ultrasonic goodness, this definitely isn’t the first time we have touched upon it. While a sound card might be exotic on a server, a hard drive LED isn’t.

Reading The Chip In Your Passport

June 28, 2025 by 37 Comments

For over a decade, most passports have contained an NFC chip that holds a set of electronically readable data about the document and its holder. This has resulted in a much quicker passage through some borders as automatic barriers can replace human officials, but at the same time, it adds an opaque layer to the process. Just what data is on your passport, and can you read it for yourself? [Terence Eden] wanted to find out.

The write-up explains what’s on the passport and how to access it. Surprisingly, it’s a straightforward process, unlike, for example, the NFC on a bank card. Security against drive-by scanning is provided by the key being printed on the passport, requiring the passport to be physically opened.

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Hackaday Podcast Episode 326: A DIY Pockels Cell, Funny Materials To 3D Print With, And Pwning A Nissan Leaf

June 27, 2025 by 3 Comments

Time for another European flavoured Hackaday Podcast this week, as Elliot Williams is joined by Jenny List, two writers sweltering in the humidity of a Central European summer. Both of our fans and air conditioners made enough noise to be picked up on the microphone when they were turned on, so we’re suffering for your entertainment.

The big Hackaday news stories of the week are twofold, firstly a cat-themed set of winners for the 2025 Pet Hacks contest, and then the announcement of a fresh competition: the 2025 Hackaday One Hertz Challenge. Get your once-a-second projects ready!

This week gave us a nice pile of interesting hacks, including some next-level work growing and machining the crystal for a home-made Pockels cell light valve, an upcoming technique for glass 3D prints, and enough vulnerabilities to make any Nissan Leaf owner nervous. We note that mechanical 7-segment displays are an arena showing excellent hacks, and we’re here for it.

Meanwhile among the quick hacks a filament made of PLA with a PETG core caught Elliot’s eye, while Jenny was impressed with a beautifully-made paper tape punch. Finally in the can’t miss section, The latest in Dan Maloney’s Mining and Refining series looks at drilling and blasting. Such an explosive piece should come last, but wait! There’s more! Al Williams gives us a potted history of satellite phones, and explains why you don’t carry an Iridium in your pocket.

Or download it your own fine self. MP3 for free!

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