https://tech.newstatesman.com/security/nhsx-tracing-app-source-code-was-released-privacy-fears

In a move designed to create the impression of radical transparency, NHSX finally released the source code for the UK’s Covid-19 tracing app last week. However, among experts, the reception was mixed.

Aral Balkan, software developer at Small Technology Foundation, expressed criticism that the source code for the server hadn’t been released, only that of the iOS and Android clients. “Without that, it’s a meaningless gesture,” he wrote on Twitter. “Without the server source you have no idea what they’re doing with the data.”