Blue Origin Structural Engineer interview questions

Since I was near the area, HR set up a time for me to visit the Kent site. After a tour around the site, I was interviewed by a structures lead, and was asked to answer a few fundamental questions. About 3 weeks later, I was contacted by the HR again for another interview, this time I was to present my resume to a panel of four engineers/leads for roughly an hour. Followed by 4 one-on-one interviews. Then the following week, I was asked to provide three references of former manager/colleagues. Finally three more weeks, the HR called to negotiate my salary.