# ESP32-S3 USB Authentication Key

A DIY FIDO2 key using an ESP32-S3, a [top-to-top](/vocab) type-C coupler, and the [Pico-Fido firmware](https://github.com/polhenarejos/pico-fido).

This was kind of my introduction to 3D modeling, as I had gotten access to a (frustrating and poorly-maintained) 3D printer when I started my (at time of writing) current job several months prior.

I'd also been wanting a USB authentication key for use with my computers, but didn't want to shell out the cash for a Yubikey. I realized for the same price, I could make my own and have parts left over.

It works well, honestly I've no complaints with the firmware, and am happy with how the casing I printed turned out. I did wind up having to dremel some of the aligment walls for the button and shave it down.

![A photograph of an ESP32 and USB-C coupler sitting inside of a 3D printed housing, with a metal keyring attached to the back](https://pogmom.me/assets/img/plog/pico-fido/2025-07-17.jpg)
![A photgraph of a 3D printed flash drive-sized enclosure with a button on the side facing the camera, and metal keyring protruding from the back](https://pogmom.me/assets/img/plog/pico-fido/2025-07-18.jpg)

### Resources

 - [Housing STL Files](https://pogmom.me/assets/stl/pico-fido.zip)
