During my PhD I created the C++ software library Harpocrates. The library serves as a transparent interface for hashing algorithms. Supporting SHA-1, SHA-256, SHA-512, and HMAC. Later with the aid of Sipos Marton added AES encryption and decryption was added. Christian Gottel added support for CRC-32. Finally, Rasmus Vestergaard helped making the library easier to use.

Since then library has not really evolved at all. There have been a few users and none have found bugs nor compliant. However, this has changed. As part of my work for my own company Obsidian Wolf Labs and new need for Harpocrates arose. A customer asked for SHA-512 hashing using OpenSSL version 3. Funny enough the customer themselves suggested Hapocrates not realising I am the original author. Another requirement was that CMake support was added. Therefore I embarked on the process of updating Harpocrates.

Whilst the updated version has been running for a while at my customer. I have not had time to upstream the changes to the original repository. Until now. Therefore, I am happy to public share that Hapocrates has been released in version 4.0.0. Which brings the ability to use CMake as build system and support is now included for OpenSSL version 3. With legacy support for version 2 still available.

Whilst CMake is now first citizen in the project, the integration could be better. Therefore, I will continue to improve the CMake experience and make it easier to integrate Hapocrates into other projects.

Special thanks to Net-X for continuing to hosting the code on GitHub and giving it a home. My current changes will be on my personal fork looopTools/harpocrates. Where changes will appear first before I upstream them.

If you want a hashing algorithm include in the library. Reach out and I will see what I can do.

./Lars

Some years back I purchased the book The things that nobody knows - 501 Mysteries of life, the universe, and everything by William Hartston (Book on Goodreads). But I never got around to read it, until NOW! This will not be a deep dive into the exact content but rather an argument for why you should definitely need to read this book.

Mr. Hartston does not dive into topics he know the answer to nor limits him to trivial topics. The tittle encompasses the concept is perfect. The book covers science, history, psychology, arts, and more. But not on topics we actually knows answers too, but those we don’t. Which makes this book a fascinating reading. Why did Edgar Allan Poe wear someone else clothes when he died_, Does Californium exists naturally on earth, and _What is the penguin population of Antarctica are just a few of the topics covered. All of which we have no answer too and some we likely never will.

So why do I believe you should read this book. Well, the book presents numerous different questions and give a rough explanation of each about why we do not know how to answer it. Some may think why do I want to read it then, if it doesn’t give answers? Well, at least for me, it prompted me to research some of the topics. Which made me learn more and gain knowledge, always a good thing I believe. Also its a good topic to discuss at a party as it is also fully of little fun facts. Like lesbian albatross are common. But more importantly, it gives us a narrow introductory gauge into how little we actually know. A certain level of humility is instilled and you will start to wonder about what of this can we one day know the answer to.

For some of the question raised my Mr. Hartston the answer is likely that we will never know. For others its a question of scientific studies. Like did the sun consume a planet? And that is just plain old fascinating. The book is for the curious, the one that wants to know what is not known. It is a gift for the arrogant, that thinks he/she knows it all. I will guarantee you there is something in the book for that person.

The book is a series puzzle with no clear answer and that is again simply fascinating. I highly recommend it for anyone who are curious and can accept to be left with more questions than answers.

./Lars

I have been thinking about why I continue to maintain this blog. What is its purpose? Is it good for me? Should I continue? Can I continue? In this post I would like to dive into this.

First of, I started this blog a six years ago, back in April of 2020. Originally my purpose with the blog was to discuss tech things. Programming, backups, network, and more. But over time it became more of just a miscellaneous blog, where I discuss whatever. Still tech has a heavy hold. But I have also discuss food and miniature painting. Yet, what very few know is that the blog started with two purposes, one I already discussed. The second was improving my writing skills. I am, still, working on a novel. But writing skill in a more literal sense rather than academic and technical sense was lacking. Therefore, I want to utilise this blog to expand this skill set and I do find that it has evolved over time. Additionally the blog gave me a way to write down my thoughts on certain topics that I thought other might need. And through this, the blog gave me a sense of purpose. So why have I been thinking about why I maintain the blog?

I have been thinking about this, because I am not happy with how rarely I post. So, I have been feeling stressed about it a little. But there is actually a deeper reason for it. At the moment I cannot share so much of my primary work without potential trouble. As a lot of my work now is proprietary and I cannot share it. Well I can if I make it very abstract, but then the fun gritty details are left out. Which intone reduce the value of the post I would make. I can share some of the work I do on the RDK platform. But it is a grey area. I can would be able to share the open source stuff. But really, that is not so interesting. The interesting stuff like hardware abstraction layers and so on, is a no go. So what would the purpose of this blog become then?

Well that leads into the is it good for me to have a blog and should I continue? Indeed is good for me, I love writing blog post and put them up online. Which answers the second question, should I continue, yes! But I want to change the rules for myself a bit. First of, I will not expect myself to have one post a month or something like that. I will write on draft posts until they are ready and then release them. I do not want to rush through a post and then half ass it. That is just not the person I am. Plus it is clearly not good for my psyche.

But what then becomes the purpose. Well! I have plans! As some have noticed, I have been writing more about mental health. In particular screen time. I would like to continue down this avenue. Not because I am professional, because I am not! But because I find that certain things work for me and I want to share it. I really do believe I can help people in this area. I do not want to become a coach. I just want to share the little nuggets I find. This is both to help my readers and myself.

I will also continue to do tech post. Probably mainly programming. But I would like more deep dives. Like how does a data structure work, write example in C or C++, maybe rust. What is generic programming, and so on. More the stuff that good engineers should know, in my opinion.

Finally, I would like to show case some other work. Which is more in regards to teaching material. But I am not sure it belongs here. We will see.

Thanks for reading

./Lars

So I have used yocto since 2024 as part of my position at Sky Labs Aalborg. Whilst, at work I mainly provide recipes that integrates into a larger yocto based project. This has made me build a few yocto based projects in my spare time, mainly focusing on creating a simple print server system and a simple storage system. So I do have some understanding about very big and very tiny yocto projects.

But, before we dive into why I love it. Let me briefly touch on what is actually is. yocto at is core is a (collection) of tools that allows you to build a custom Linux distribution. Some would argue that it is only for constructing Linux distributions for embedded devices. Yet, I have seen it used for building very heavy distros no for embedded devices. Also, it is a project under the Linux Foundation.

So why do I like and why did write this post? Let us start with the latter. Amongst my colleagues and on forums online, I have heard a lot of arguments against yocto. Must circling about when a project gets large enough, it gets too difficult to manage or the build gets heavy. Some even suggest switching too alternative tools, one popular option seems to be BoB.

Okay, let us talk about why I like it then. Firstly, getting started with yocto is super simple! The Yocto Project Quick Build guide, pretty much sets you up for success. One thing here, the guide is focused on Debian and Ubuntu based distros. However, it is fairly easy to find a guide for how to get it running on OpenSuse or Fedora. When you have followed the quick build it is easy to advance on to the next steps.

Secondly, manuals! To me it honestly feels like the yocto project took inspiration from freeBSD and its in depth handbook or ArchLinux wiki. If it is not in the documentation why are you even doing it???? That of course is a joke. The manuals are quite and an excellent resource

recipes.

https://bootlin.com/training/yocto/

I originally planned this to be a post on Mastodon, You can follow me here if you want. But, it simply got to long for that format. So here it is, in a longer form than I originally planned.

I got asked an interesting question by a junior developer a couple of weeks ago. The question was quite simple but interesting; “What do you do to wind down”.