Very casual but have set answers to who you'd like to work with and/or what you'd like to work on and why that fits into their work. The personalities of all the interviewers were very different so being able to adapt to different people is a strong plus.

Initial call with recruiter and was told there would be a call with the hiring manager in a week but didn't receive a response until a month later from a different recruiter (first recruiter had left the company). Meeting with hiring manager was straightforward asking to desescribe my research but the manager was not knowledgeable in the field and fairly rude.

For the initial phone interview(s), be prepared to answer questions about your work in detail. They want to ensure that you were substantially involved in what you claim to have worked on. For the in-person interview, treat this like any academic postdoc interview. During your job talk, be prepared to defend your work but do not get defensive. Questions are usually asked a few minutes into your presentation and will be peppered throughout. Stay focused and engaged. Also, don't neglect the HR interview. If you are fundamentally involved in your work and have contributed significantly to it intellectually and technically, you will actually enjoy the interview process. Good luck!