I applied online. The process took 3 months. I interviewed at Caterpillar (Peterborough, England) in Feb 2019
Interview
Aptitude test - Phone Interview - Assessment day
The aptitude tests were standard, after that I had a 30 min phone interview based on motivations - answered using STAR. The Assessment day was 7 hours, relaxed and very technical. Offered to cover travelling costs. Decent.