It was very time-intensive. It’s hard to quantify because none of us was doing it on a professional capacity, so, time was irregularly spent on long nights and weekends, but roughly, it took about 3 calendar months, because the more serious activities towards design and production started around April, and the badge was finally assembled on June 22nd (ON THE DAY OF THE EVENT’S KICK-OFF!). @rac2030, @ursm and I spent countless nights (and some days too) working on it and its assembly.
We were fortunate to have early and fully committed support from Sensirion and u-blox as sponsors, and their commitment went well beyond purely sponsoring, they actively helped with reviewing designs, offering prototyping facilities, even a full afternoon debugging session at some point to chase down a bug. Also very lucky to have R2Prototyping in Zurich, which as well helped us big time on the assembly process, and sponsored all the industrial-grade machinery to solder the boards.
In terms of production costs, we spent approximately CHF 4.5k (EUR 3.9k) to produce 120 badges. This cost includes all material expenses (including the lanyards) but excludes the sponsored value, i.e. the NINA ESP32 microcontroller and the Sensirion sensors.