OpenTrafficMap(opentrafficmap.org)
289 pointsby moooo99Apr 29, 2026

12 Comments

solarpunkApr 29, 2026
Cool, but it there's no links for more info, and it doesn't seem to work in the USA at all.
moooo99Apr 29, 2026
The project was shared as part of a talk at Graz Linux Tage. You can find it here, unfortunately it is only available in German

https://media.ccc.de/v/glt26-688-c-its-mit-einem-esp32-ampel...

RobotToasterApr 29, 2026
Is there a link to the hardware they mention in the description?
MaxiousApr 30, 2026
They built their own circuit board but the core module that does the 802.11p is just a ESP32-C5
RobotToasterApr 30, 2026
Yes, I understand that. The translation makes it sound like they have published the software and design, or are somehow making boards available.

>To improve coverage, we need your support! We have built a board with *ESP32-C5* and *PoE* that allows you to capture *C-ITS* packages yourself, and provide us for our face-up card, or process it yourself.

Edit: found it, https://codeberg.org/opentrafficmap

refulgentisApr 29, 2026
Pastebin here containing AI-generated English translation, LGTM: https://pastebin.com/fK5Atwzg
localhostingerApr 30, 2026
Happy to see this popping up here, I watched the Linux Tage talk last week. The demo just kept getting better and better, to a point where the audience just interruptively cheers and claps away. I know nothing about the contents, but this warmed my heart. True hacker project!
walrus01Apr 29, 2026
If I had a dollar for every time I've seen an American on the Internet assume that anything published in the English language must be US-centric...
rootusrootusApr 29, 2026
Conversely, if I had a penny for every time someone complained about Americans... ;-)
dawnerdApr 30, 2026
That's one way to get rid of our (US) pennies now that they're useless!
exegeteApr 29, 2026
I mean I don’t anyone thought this was in the US since the UI is not in English. Maybe it’s more of, this neat, wish we had it here?
amazingamazingApr 29, 2026
This is an American site to be fair. Mapbox is also an American company.
bravoetchApr 29, 2026
You still wouldn't have nearly as many dollars if you subtracted the times those people were correct in that assumption. Personally I assumed the site would be global. It doesn't have any info though, so I rely on finding out somewhere else I guess.
lucideerApr 29, 2026
> Personally I assumed the site would be global

The only reason you would assume a site would be global is if your definition of "global" is "works in the US" & you never bother to check for support of other countries. I live in the anglosphere outside of the US & I encounter more than enough US-only web projects for that not be to a default assumption I hold.

Most sites are not global - it's very odd to assume they would be.

BigToachApr 30, 2026
Another reason could be that calling this OpenTrafficMap gives an impression that it is similar to OpenStreetMap, which is global.
lucideerApr 30, 2026
OSM launched as a London / UK project. Even today, it's a lot more comprehensive in some parts of the world than others.

If I got the impression that it was like OSM, that would give me the impression that it is only as global as my contributions to it (which is what lead to OSM becoming global).

MrDrMcCoyApr 30, 2026
Expecting support globally is of course unreasonable. Expecting it to be designed to be somewhat location-agnostic for contributors and including some obvious docs (which could just be "coming soon" or "here's what we need to expand") is pretty reasonable to me.

I don't get why there isn't even a stub repo for a mobile app to contribute with. Or am I just not finding it?

perching_aixApr 29, 2026
Is expecting something to work in the US the same as expecting it to be US-centric?
hamdingersApr 29, 2026
It seems pretty weird to use all English words in the domain for a service that offers no English translations and operates in no English speaking countries.
walrus01Apr 29, 2026
The Germans and Danes and Swedes and Norwegians I see on the Internet developing and publishing software often have a better grasp of the English language than many born in the USA Americans.
ufociaApr 30, 2026
That's true for Scandinavians, Germans are not as gut.
aspect0545Apr 30, 2026
Ja ja, maybe not as gut as the Scandinavians, but still better than many US Americans.
moooo99Apr 29, 2026
The map is based on international standards and technically it does not restrict locations to German speaking countries.

The authors of this project also shared that they intend on publishing more around this project. This seems to be mostly an early demo that was intended for the live event.

estimator7292Apr 29, 2026
OpenStreetMaps works in the US and much of the rest of the world.

It's entirely reasonable to expect that a project with an extremely similar name would also work in most of the world, which just happens to include the USA.

ufociaApr 30, 2026
It does have an English name, so why the surprise?
mahsa32Apr 30, 2026
I did scroll across to the UK and was disappointed that there's none for here.

But I'll probably add my own receiver soon!

felixguendlingApr 29, 2026
It's based on Car2X/Vehicle2X data that's sent unencrypted and can be received with chips you can order from China.
rootusrootusApr 29, 2026
Will be interesting to see how it fares when it does come to the US. It seems like there are some cars that already have the tech installed. But the US is allegedly more interested in the cellular version, which I am guessing is not as easy to pick up with a simple receiver?

My gut feeling is that this seems like one of those things likely to face a lot of backlash when it becomes widely known.

felixguendlingApr 29, 2026
I guess we only find out if some people order those chips and check if there is some data. From my understanding the idea is the same like maps showing air planes or ships (for ships it’s AIS). So without volunteers/pioneers who participate we won’t know. It seems like traffic lights and trams also can send data.
uyzstvqsApr 29, 2026
The site is definitely lacking. It's half in German, half in English.

The concept is that there is this protocol called ITS-G5, which is a European profile of 802.11p. Vehicles and traffic infrastructure can transmit telemetry on 5 GHz. Other vehicles and traffic infrastructure can use it for situational awareness.

This website collects that data using local receivers and aggregates it onto a map, similar to what website like ADSB-Exchange do with ADS-B.

What is concerning is that vehicles appear to broadcast a MAC address. Does this mean that ITS-G5, 802.11p, and C-ITS could be used for persistent tracking?

alexpotatoApr 29, 2026
This should be a top level comment as it has a ton of useful info and can be voted to the top.
softgrowApr 30, 2026
Reading the translation of the talk, public transport vehicles have a persistent MAC but for private cars the MAC address changes every 15 minutes.
ufociaApr 30, 2026
That still doesn't seem very private.
BarbingApr 30, 2026
Particularly anywhere rural or off the beaten path
moooo99Apr 30, 2026
You wouln‘t really have the kind if hardware there. The communication relies on a multi hop mesh that would‘t work anywhere without sufficient coverage.
izacusApr 30, 2026
You do know you have a unique ID displayed on a big tab on the vehicle, right?
interloxiaApr 30, 2026
fy20Apr 30, 2026
For a vehicle with a highly visible unique identifier on the front and rear? In my country basically every private carpark has ANPR cameras, the tech is dirt cheap now.
rompicApr 30, 2026
As discussed in the video they are not resetting the packet sequence number though, making it easy to match them with the other data transmitted.
firesteelrainApr 30, 2026
Did they re invent APRS?
antmanApr 30, 2026
What about the traffic lights on the map do they also have transmitters?
moooo99Apr 30, 2026
Yes, they also have transmitters. The traffic lights send out MAPEM and SPATEM messages. They describe the layout of the lanes at the intersection as well as the red/green phase timings of the signal.

In Graz, the city where the authors live, there are 165 of such signals planned.

wummsApr 30, 2026
> What is concerning is that vehicles appear to broadcast a MAC address.

Somewhat related: 'Your car’s tire sensors could be used to track you': https://networks.imdea.org/your-cars-tire-sensors-could-be-u...

xd1936Apr 29, 2026
I haven't seen a theme on OSM data look this modern and fresh before. Beautiful color palette and iconography!
stevenhubertronApr 29, 2026
It's a Mapbox theme
azza2110Apr 30, 2026
Agreed - it is very similar to Google Maps.
pxebootApr 30, 2026
It looks like Mapbox Standard [1]. While a free tier is available, most sites are going to need a paid plan.

[1] https://docs.mapbox.com/map-styles/standard/guides/

maelitoApr 30, 2026
Can you try this one ? Though not as flashy, it's a step away from most OSM styles.

https://cartes.app/#13.13/47.06727/15.44801

mlaretallackApr 29, 2026
Found out about this today, up until now 802.11p hardware is very expensive, and so you cannot easily do anything with V2x messages like CAM or SPAT, but the fact this was done with sub £20 hardware is really interesting.
rompicApr 30, 2026
Fully agree. That's the most interesting thing about this.
Cider9986Apr 29, 2026
>WebSocket getrennt

Hug of death? Nothing loads.

poormanApr 29, 2026
I wonder if this could be used to track location of the vehicle
embedding-shapeApr 29, 2026
Isn't that the point of the project? I'm seeing a bunch of tracked vehicles, although they all seem parked at the moment.

Does Graz not have night bus service?

flickenApr 30, 2026
The night bus service only runs the nights "before" Saturday and Sunday[1]. It's a small university city with 300k population (600k greater metropolitan area).

[1] https://www.verbundlinie.at/en/customer-service/arriving-in-...

embedding-shapeApr 30, 2026
> It's a small university city with 300k population

Made me smile, I'm from outside a city we used to call "big city" when I was growing up, it had ~110K population and is the 9th largest in the country or something :P Anyways, that city still has night service, so not sure why a city with three times the population wouldn't, especially if it's a university city.

fragmedeApr 30, 2026
If it's not able to support a robust bus system, it's not a city, just a really big town.
modinfoApr 30, 2026
It will be nice if we everybody could just add own receivers, then it will be quickly cover more cities. But still nice project.
modinfoApr 30, 2026
Ahh, it send automatically to website! "mqtts://cits1.opentrafficmap.org"
RobotToasterApr 30, 2026
fy20Apr 30, 2026
How does the hardware work? It seems like there isn't any radio hardware other than the ESP, so that can natively receive the ITS-G5 messages? Why not just use an ESP board with native ethernet then?
rompicApr 30, 2026
They are doing it with the standard WIFI receiver. Currently they are sending the Wireshark dumps to a backend for processing.

According to their presentation they are working on a rust firmware to do everything on the board.

ablationApr 30, 2026
Huge performance issues for me trying to use it on Chrome. But I like the idea.
CountGeekApr 30, 2026
I recently learned that with smart traffic lights cyclists can change traffic lights -https://nltimes.nl/2026/04/28/new-app-turns-traffic-lights-g...
alex_dufApr 30, 2026
Rotterdam is using rain data to asjust traffic lights. Bicycles are waiting less at intersections. They also make the amber light longer to give you time to break for farther away and avoid a fall.

https://popupcity.net/insights/rotterdam-traffic-light-prior...

jorisborisApr 30, 2026
For a while I tried creating traffic-light-free bicycle routes from my home in the suburbs to my office in Amsterdam center (because intersections, especially with trams, can sometimes take a long time.

Unfortunately there was no API with data on which intersections have traffic lights and I had to build these routes manually in Strava using satellite images.

I did learn in the process that some traffic light data is actually available from the government, but only for selected partners. The Flitsmeister app for example has it and shows at some traffic lights how long it will take for the light to turn green (in a car, not on a bicycle)

Myzel394Apr 30, 2026
I don't get this at all. Is this a live view of the traffic lights, buses, and more? How do they get the data?
maelitoApr 30, 2026
We need global open congestion data. At least on the european scale.

It's important so that alternatives to Google Maps and Waze (Google) can emerge.

To create congestion data, one needs to own an OS with location tracking, or be an international mobile network. Won't happen.

[disclaimer : I work on an open source alternative to big tech's maps]

crimsoneerApr 30, 2026
What is the OS alternative? OSM?
maelitoApr 30, 2026
https://cartes.app. Based on OSM of course, but OSM is just a geographical database, with lots of incomplete UIs built on top by the community. Cartes is one of them, we're trying to make it complete and modern :)
yosaminoApr 30, 2026
That looks pretty cool - sorry to have a complaint immediately:

When opening the map on Firefox/Linux zooming to like a France-size view and then not doing anything, the view keeps scrolling up and down relatively slowly, but very annoyingly.

Zooming all the way out, it looks like the globe is jiggling back and forth ever so slightly, but continually.

I've recently seen this happen on another mapping application ( cannot remember which one) so it's probably in down the stack somewhere in a library you are using.

cheschireApr 30, 2026
How would you overcome the data source trust issue? In open data collection you either fingerprint the data to ensure validity or you anonymize the data to provide security, but striking the balance between the two seems like the biggest of hurdles in an effort like this.

The risk of the data being invalid seems as risky as the privacy implications in this case.

CodeCompostApr 30, 2026
Am I the only one here who thinks this is intrusive?