Initial 30 minute call with HR. Then a 1 hour interview with the 2 Senior Devs who went on to ask some behavioural questions. If successful you are then sent a coding exercise. Finally, another 1 hour interview with the 2 Senior Devs to review your code and talk more about the role. So, 4 steps in total, but the process did get drawn out needlessly - almost 2 months in this case when it could have taken 2 weeks max.