It involved a couple of informational interviews, an assessment interview, and then a series of back to back assessments with senior leaders (such as heads of functional units). In total it was 6 different interviews.
I applied through a recruiter. I interviewed at Brimstone in Sept 2022
Interview
The recruiting organization made it sound like the role was EXACTLY what I do in my current role as a lead process engineer with regards to scale up/pilot plant design and operations, and that the pilot plant would be in Oakland (it's not - it'll be outside of Reno). The role they're actually looking for sounds more like a lead chemist position. The interview with the head of engineering was extremely painful for both ends because of this discrepancy in expectations.
Interview questions [1]
Question 1
What is pH? many other chemical synthesis questions