3 interviews in total plus a competency test.
The competency test touch on all the things you would expect a developer to know about, APIs, concurrency, OOP, command line interface and asynchronous requests.
I found it to be a moderate test and essential for most developers.
The interviews were human driven, by that I mean, it was more focused on how your personality fits within the company and the views of the company, which myself, I enjoyed.
The ethos that was transmitted was one of care and general well-being of customers, works and society at large (in this case the NHS ).