@concretedog

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Tinkerer, creates lots of stuff including the pay as you feel quarterly #SOURCE magazine https://sourcemag.co.uk/
Writer/Has Written for Raspberry Pi Press, Hackspace Magazine, Tindie, Kids Code CS, FreeCAD and more.
A couple of books, "FreeCAD for Makers" and "Design and RP2040 board with KiCad" published on RPI press.

Forged in the heart of a mountain.

Less than a month left until the Free and Open Source Software Developersโ€™ European Meeting (FOSDEM)!

With over 900 events already announced, here's my little companion web app that works on desktop and can be installed on mobile to help you with the planning: https://fosdem.sojourner.rocks/2026

New features this year (more improvement suggestions welcome):
- Speaker biographies (click on the person's name or visit the speakers page).
- Bookmark export.

#fosdem #pwa @fosdem #freesoftware #opensource

FOSDEM 2026 | Sojourner

FOSDEM conference companion PWA

Since posting this 2025 year-long keogram, there have been quite a few questions asking how it was created and what is visible. In this thread I'll try to explain how it all works.

ok, I think I'm done with this project?

it now plays conway's game of life and creepy noises, all from a single STM32G431 MCU with minimal external components, which is really all you can want from some lowfi analogue TV stuff.

In the process of making the audio work I ended up changing from channel 2 to channel 3 to get rid of the interference from the 48MHz clock I use for audio, which also means I'm running the CPU faster and get a little bit more processing time. Number of external components is now 4 resistors for mixing the baseband video signal and 5.5MHz audio carrier. Unfortunately going to the higher frequency also meant losing some signal quality, since I'm operating the internal opamp even more out of spec. Or maybe I'm just unlucky and there is more interference on that frequency here.

Join us at @tog Hackerspace for a hands-on afternoon of mending and repair. Bring your broken bits - and our amazing team of fixers will help you give them new life.

๐Ÿ“… Jan 18 | ๐Ÿ•› 12โ€“4pm | ๐Ÿ“ Tog Hackerspace, Kylemore Road, Dublin 12
๐ŸŽŸ๏ธ Tickets: https://www.eventbrite.ie/e/repair-cafe-tickets-1977495649721

@concretedog Yes, but better. It fixes the 2 main Jupyter problems. Notebooks are fully reproducible and have no hidden state, and notebooks are pure Python code and play well with Git.

https://marimo.io

marimo | a next-generation Python notebook

Explore data and build apps seamlessly with marimo, a next-generation Python notebook.

@concretedog Right now I'm also looking into Conan for C/C++ package management. Students will have a cross-platform, reproducible toolchain that allows them to automatically create software bills of materials.

That's the boon and bane of OSS, you never stop learning about ever better tools. Every year I teach my software engineering class, I update about 20-30% of the content.

https://conan.io

Conan 2.0: C and C++ Open Source Package Manager

Conan is an open source, decentralized and multi-platform package manager for C and C++ that allows you to create and share all your native binaries.

@concretedog To answer your original question where and why OSS is more useful and innovative: I've adopted the uv package manager and marimo notebooks into my curriculum less than a year after their first release, because it was clear what value those provided over the traditional tools. Commercial software just cannot be evaluated and acquired this fast and then there's always the risk of sunk cost if that doesn't work out.
@alexnetogeo @concretedog @ultrazool @volcan01010 ยฃ1000 per desk buys you a lot of open source training and consulting
@avian @concretedog That's because a capitalist mindset only deals with price, not cost. Ask any stay at home mom about that one.

@concretedog I think you could name anything academics do and find open source works better, but maybe I'm in a happy bubble!

It's definitely true in assessment. Commercial systems are expensive, limited and hard to work around when they go wrong. There are lots of widely-used, good, open-source assessment systems. The Moodle Quiz and associated plugins is I think the most popular example.
In my field, maths, there's STACK (https://stack-assessment.org/) and the thing I work on, @numbas.

Because they don't have to track users or depend on a central service, they can be hugely more robust and resilient.

STACK

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