The omnipresent Andrew Back has asked me to design a small board / badge for the upcoming Wuthering Bytes Workshop in Hebden Bridge. We decided on a simple circuit -- something based on littlewire (thanks!) -- and Andrew gave me creative freedom. Below is the result. It's released under the Solderpad license. The source is here, and the Gerber package is here.
Please help us by having a look over the design files, and let us know if you spot any problems!