I emailed the Design Lead directly as someone I knew just finished a coop there. He liked my resume so he setup a technical interview. Usually there are two interviews: HR and technical but I skipped the first one. He took a long time to ask me for an interview after I sent him an email but I emailed him way before they were thinking about hiring for when I wanted to work. He asked me some questions about my resume and my previous work experience as well as some specific technical questions I'll talk about later. He seemed very laid-back but also very knowledgeable as well. I asked him a very difficult question at the end of my interview and he recovered very well and answered my question to my satisfaction. The nice people at Cummins understand coops very well and how to deal with them.