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Server Charm

Photo of the server charm hanging from the belt on jeans trousers
My server charm

In a Tracks video about Sneakernet, I've learned about Actinomy's Server Charm workshop. The idea is to guide people into building a portable server using cheap electronic components, thus educating them about the operation of a network and raising awareness about the domination imposed by large companies hosting our network. The device relies on the ESP32-C3 microcontroller, a very versatile chip with a Wi-Fi emitter, powered by a used vape battery. The whole thing holds in one's hand and can be carried anywhere. People can connect to this portable Wi-Fi access point, and thanks to a "captive portal" trick, a webpage shows up immediatly – for most phones – on the user's screen.

Screenshot of a PDF document
Actinomy's Server Charm Manifesto, which details what to do to build your own server charm

I've never really got into electronics project, but this one seemed very easy to replicate. The software part was the easiest for me. I then learned how to use the FreeCAD modelling software to design a box for my little contraption. If found FreeCAD's approach of modelling very neat: draw a rough skecth of your object, then write a list of logical constraints about points or segments, and a logical solver generates the object for you. There is a bit of a learning curve: I followed MangoJelly Beginners Tutorial, that appeared to be recommanded on some parts of the internet (aka. Reddit).

Screenshot of FreeCAD Assembly workspace, with the box in it, as two parts: a bottom and a top
The case model in FreeCAD

I then 3D printed the box – twice, because my first measurements were a little too tight – and soldered the components together. Compared to the original design by Actinomy, I've added a power switch to turn the device on and off at will. The soldering part was also kind of new to me. The main difficulty I faced was the reduced spaced I had to fit everything into, but I got it to work with some patience.

Photo of the contraption on a wooden desktop, white top with a hole where we can see the electronic chips inside Photo of the contraption on a white floor, sealed up
The final object, with and without the small panel hiding the inner electronics.

Finally, I had to choose what to put on this portable website. I finally ended up writing a list of projects and things to do, by gathering some ideas I've had in the past, some of which were already achieved, some abandonned, and some left for the future. I figured that if someone randomly found out about my server charm and connected to it, they would certainly be interested in some of those. Though, as someone said in Tracks video, if you want to know about those ideas, you'll have to get close to me!

Demonstration of the user experience: turn on the device, connect to the access point and the page opens up