Someone with both epidemiological and software development experience who is developing and evaluating scientific models to try and measure risk, exposure, and control effects for a DCT app or DCTS. An end user of a DCT app. Typically a resident of a country or state with a public health authority. Normally PHAs provide a DCT app, but it may also be a private company for its own staff. An Epidemiologist without computer science knowledge or skills. They are trying to stop the spread of a disease. A Public Health Authority who have staff with a range of skills but who are trying to protect a population from the spread of a disease by providing advice and systems to control the spread. Somebody working for a PHA that is trying to trace and contact those who have been at risk of disease exposure. May not be a trained epidemiologist. A group of DCT app users whose geographic remoteness or social standing (E.g. lack of wealth) may mean that some technology approaches available to richer members of a country or state are not open to them. This is a KEY GROUP within Herald's design goals. It includes, but is not limited to, those who are elderly, or very young, or homeless, in traditional communities, are poor, do not have access to ICT, do not have regular Internet/Data connectivity for devices, or are disabled and find using technology difficult. A nation state who is trying to compromise a DCTS system for economic, military, political, or society disruption / propaganda reasons. They may want to access DCTS data of another nation to track people or force people in to a location at a time of their choosing. (aka 'the Westminster attack') Someone who seeks to control and monitor an individual through technical and emotional abuse/coercion means. They may misuse data in a DCT app to see that a person is mixing with others or travelling out of area. Well funded and organised groups that would seek to exploit a DCTS for economic gain or individual coersion Main reference implementation since v1.3. All new features are defined and tested here first. Swift and iOS Herald libraries are really specialisations of the C++ project's components. Opensource hardware designs. May also include specialist hardware driver code for devices not supported by Zephyr natively. From GovTech in Singapore From GovTech in Singapore From GovTech in Singapore Adapter library - exposes the Herald C++ API into Node.js exports. Thin adapter layer. For a human, the DCT hash ID. For other sources, their IDs. E.g. radiation whether a local dosemeter or one from a building's beacon. Start and End date times. For 'live raw exposures', the last time for which a reading was given in the period. Double for now. Perhaps a more complex value in future. E.g. HumanProximity, UVRadiation, OutdoorLight, IndoorLight, AudioLoudness E.g. BluetoothRSSIMinutes, AudioDistanceEstimateSeconds, LumensMinutes, RadMinutes, etc. E.g. Potential Risk (non confirmed cases), presumptive risk, confirmed risk (E.g. from exposure notification confirmation after PCR testing) E.g. Exposure Confidence Updated (wasConfidence, nowExposure), Live Exposure Changed (was, now) Calculate Risk Score (Exposure Manager, Configuration, Metadata) -> Risk Score, Update Risk Score (WasScores (Periods may overlap), Exposure Change Details) -> Risk Score For human proximity, the status of the individual you are proximate to (presumed healthy, symptomatic-untested, tested-positive, tested-negative) would affect the confidence score, which in turn would trigger the exposure manager to update the risk score. Lowercase components are packages/namespaces, uppercase are classes/structs. Exposures are things that can be directly measured to some degree of accuracy. E.g. Proximity to a person, temperature, UV, radiation. Risks are things that can be estimated from information about the person at risk, and the risk environment (such as exposures). E.g. Risk of having contracted COVID-19. All projects have Herald for C++ as an upstream dependency. It will therefore be necessary to tightly test and control C++ API releases.