Top posts

Every blog post that took off on Hacker News, ranked by the votes of its best submission. 326 posts.

Hardware & Electronics
2025
10

Root shell on a credit card terminal

In this project, I started to reverse engineer payment card terminals because they seemed to be an interesting target for security research, given the high stakes involved. Although I initially didn’t know much about this industry, I did expect a ton of security features and a very security-hardened device. And to…

28

Why is my CPU usage always 100%?

If you’re new to this series, I’ve been documenting the process I went through upgrading my old PXA166-based Chumby 8’s 2.6.28 Linux kernel to a modern 6.x version. Here are links to parts 1 , 2 , 3 , 4 , 5 , 6 , 7 , and 8 . At this point in the project, all of the main hardware peripherals were working great. I…

29

MacBook Pro Insomnia

Update (01.08.2025): fixed broken link, typo, clarified problematic behaviour For a number of years now I have a MacBook Pro Silicon M1 Max. It worked beautifully. Then, seemingly out of nowhere, I started noticing that the battery drained over night when I left the notebook somewhere, not connected to power. This got…