curl -LO https://github.com/cami/ArduinoCore-nRF52/archive/v0.3.0.tar.gz
du -H v0.3.0.tar.gz
shasum -a 256 v0.3.0.tar.gz
Add https://raw.githubusercontent.com/cami/cami.github.io/master/package_nectis_index.json
as an Additional Board Manager URL
.