ALTEN interview questions

One recruiter reached me out on Linkedin. First call, it was to talk about the company - Recruiter Second call, it was to talk about my professional experience - Same recruiter Third call - It was discussed about a project to be done (Hotel booking) - Again discussion about my professional experience and some technical questions. The project consists in create a API for booking a room. I've sent 3 days later the third interview. After 2 weeks, they approached me to make an offer.