Took quite some time. Had about 4 different phone interviews, each with increasing technical complexity and difficulty. Finally got a face-to-face interview that took about 4 hours. Consisted of a 90 minute practical exercise. I had to design and architect a solution, but also develop the project plan and present my solution.
Presented solution to peer architects that further grilled me on the design and architecture with some brutally challenging questions. Then I had to present the solution to a panel of 'mock CTOs and CIOs' with even more questions and challenges. I made it through all of that. A week later I was brought back in to meet with one of the directors face-to-face and further get grilled. All these interviews took about 7 weeks before an offer was made. Then I spent another week haggling and negotiating perks and salary.