Code is truth. This document is correct at the time of writing, but the system is still in development, so there may be detail changes before release.
In the interests of expediency, this paper concentrates on the most important privacy and security challenges involved in building a contact tracing app that is part of a wider public health management effort. There is much more in the security and privacy design, but those issues are not unique to a contact tracing app.
We intend to open source our codebase once the design is finalised. The documentation accompanying that released will supersede this paper.
There will be multiple releases of the app as the government’s response to the COVID-19 virus progresses. Not all features detailed here will necessarily be in the initial release.