Jan

In Austria, price increases are only allowed once per day, at 12:00. There, it’s cheapest to refuel right before 12:00 and most expensive at 12:01, but at least you can plan a bit better.

The idea that centralized fuel price data (held by the Cartel Office) would benefit customers was good. Now that gas stations are apparently using the data to spy on each other, it's a problem. How useful is it to know that a station has the lowest price if it may shoot up before you get there?

Average Vehicle count per 15 minute time bucket over 24 hours from several car counting sensors in Hamburg, Germany. The line chart looks much smoother than the price chart just one big wave starting at 3:20 with its peak at 12:30.

If you’re wondering (like I was) whether waves of commuters correlate with prices: no. Here’s data from Hamburg’s car-counting traffic sensors plotted over a day. If we use car volume as a proxy for demand, then demand doesn’t correlate with this price pattern.

It doesn’t make sense to raise prices only a little, because your competitors are still cheaper. So they raise them sharply. Others follow very quickly, and the next cycle starts.

But how come?
This pattern isn’t correlated with supply or demand at all.
It’s a tactic to extract the most from consumers: stations lower prices to be the cheapest around for a while. At some point, prices have to rise again, and that increase is initiated by the big gas station chains.

Line-chart of average Diesel, Super E5, Super E10 prices over 15k gas stations in germany for one day. Seven sharp increases followed by slow decreases.

This pattern can even be observed in the average fuel price across all 15,000 fuel stations in Germany. They’re all in sync.

Line chart of Diesel prices of one gas station for one day. There are several sharp increases, followed by slow decreases. Cycles are about 3-4 hours apart from each other and there are not such cycles at night.

Looking at the price of diesel at one gas station over the course of a day, there are several sharp increases followed by slow decreases.

Line-Chart of fuel prices of one gas station in germany, showing Diesel, Super E5 and Super E10, all on the rise from around 1,70 € to almost 2,10€ per liter in the past few days, while they were relatively steady the three weeks prior to that.

This chart is from mcsprit.de, a site a friend (hi Max!) and I built using data from the German Cartel Office. It shows #fuel prices over about a month for one particular gas station.

Fuel prices go brrr in #Germany right now.

#CivicTech #dataViz

Terminal output, starting with uninteresting headers from CURLing a site, followed by the LLMs output. The original LLM output is in german. Here is the english translation: Here are the next collection dates from the waste collection calendar, sorted by date: 12 February 2026: ⚪🔵
 13 February 2026: ⚫
 20 February 2026: ⚫🌿🟡
 26 February 2026: ⚪🔵
 27 February 2026: ⚫🌿🟡
 6 March 2026: ⚫🌿🟡
 12 March 2026: ⚪🔵
 13 March 2026: ⚫ Emojis: ⚪: Blue paper bin ⚫: Black residual waste bin
 🌿: Green organic waste bin
 🟡: Yellow recycling bin/bag Please note that the collection dates are listed starting from the current date (11 February 2026).

Made a script to grab a waste collection calendar HTML table from a site and pipe it to an #llm, prompting it to list the dates.

Its nice and all, but every time it gets something else slightly wrong 🤷

(translation in alt text)

🐇

This is so damn awesome! Congrats on such a nice build :)

Good guess, it’s indeed ratatui!

3d printed case of my cyberdeck. With a 3x3 key pad, a small and a large OLED and a physical button.

Internals of the cyberdeck, including a raspberry pi and a powerbank.

Cyberdeck without the lid, showing the wiring and usb-c port (for power) of the deck.

My #cyberdeck build is almost done.
#3dprint is complete, parts are assembled but not painted yet.
Still working on the #rust TUI application that runs on the main screen.

#freeCAD

this elevator thing is brilliant btw

This is exactly what I need right now. Thanks :)

Heat inserts are so awesome!
Discovered them way to late.

Thank you so much for all your nice messages! It's been a typical Monday, and they really cheered me up :)

I think I managed to capture most of them in a picture, which I'll be adding to my blog post about this project:
jflessau.com/projects/ret...

The display on my retro cube showing „this is dog“, which is the part of a message that fits on the screen. If this were a video, you would see the text line moving to eventually display all characters.

🤩

3d printed housing for a raspberry pi zero w and an OLED, showing a text message: „Low-res, high vibes“.

I made a website to control the content on my retro cube.
If you’d like, send me a message :)

retro-cube.jflessau.com/form
user: retro
password: cube

#3dprinting #pi #rust

100% this!

I made a housing for a #pi zero, an #OLED, and a dial for navigating between the views:

- Date & Time
- Weather
- A message fetched from a server

The server hosts a web form to update the message.
I think the colors turned out pretty cool :)

All written in #Rust and designed with #FreeCAD.

Switched from #blender to #FreeCAD for my #cyberdeck build and finally gathered all the hardware parts. #3dprinting it tomorrow! Still not sure how I’ll paint it, though.

A small part of me wishes people who start hitting the gym in January would give up sooner. This year most stayed until March and it was so crowded.

Peak commedy 😅

Had some fun with fuel price data from the german cartel office and wrote about it.

Teaser: Very synchronized prices of two gas stations, different companies, 5 km apart, no clear line of sight.
[one frame = one station]

#data #datascience #blog #opendata

jflessau.com/projects/gas...

A screenshot of a website showing a search bar for location and zip code at the top, a map of Hamburg in the middle, with pins and prices for petrol stations, and a list of petrol stations below the map, showing the first two with their name, zip code, price and the time of the last price update. It’s 1,49€ at 21:20 for the first station and also 1,49€ at 21:00 for the second one. The petrol station names are: Raiffeisen Energie Nord GmbH at zip code 22952 and the second one is Calpam Express 6-22h Tanken at zip code 22941

A friend and I built mcsprit.de, a website to see real-time gasoline prices in Germany.

Prices change so often that you’ll likely see a different one by the time you actually arrive. That’s why we’ll have some fun with time series prediction models.

#civictech #solidjs #rust #ml #datascience

First 3d print for my #cyberdeck project turned out so well.

Measurement for all the parts were correct 🤯
But I forgot some parts 🙄

Anyway, super happy with the look and feel.

#raspberry #pi #3dprint

Recently discovered the subreddit r/cyberdeck, and it's the coolest thing ever!
I'm now building one with two OLED displays, a 3×3 keypad, a dial, etc.

Can't wait for the first one to come out of the 3D printer.
The UI will be built with ratatui.

#cyberdeck #blender #3dprinting #rustlang #ratatui

Thanks for explaining :)
Makes perfect sense. I got burned trying out surrealDB recently and ended up going back to Postgres as well. Still keeping an eye out for other interesting DBs to try. Maybe not for production, though.
But sqlx in rust is just so damn good.

Curios to know why you chose Postgres as Gel‘s successor.