Easy interview process; however, terrible handling from the HR person and CEO himself.
I signed a contract, got an appointment at Ausländerbehörde 8 working days later. Just 15 days before my appointment, HR stopped answering my e-mails for a whole week and called me one week later to inform me my contract was withdrawn due to visa issues. There was no prior warning, I was very transparent about my visa situation when the offer was made. Additionally, I had no visa issues except changing my visa status- which was going to be handled anyways in 15 days!
There can be legal grounds to everything; however, there is also the moral/ethical side of it. Once a company makes an offer, a prospect plans their budget accordingly and possibly declines other job offers. Especially as a foreigner, you need to deal with visa, which requires quite a lot of planning. How I was treated was very unprofessional and shows the quality of the company itself.
Additionally, after passing the first round of interview and completing the task, you meet the CEO. This interview showed me that the company has no ambitions to grow and improve.
Go for it if you need a job but don´t expect much out of this company. You will not grow and it will make 0 impact on your CV.