I should have taken the red flags from reading other reviews and known not to apply for this company. As other reviewers said, HR is very dis-organized and not professional. It has been over 4 weeks and did not hear anything back at all from them after the interview and not even any word on my interview expenses reimbursements until I had to pro-actively had to request my money for the expenses they said they'd pay for. Very negative feeling and experience with this aspect of the interview. Would not recommend the experience and rather go for companies that treat candidates in a more professional manner.
Interview wise, it started with talking to HR about general requirements. Your typical HR interview about why I want to work there, my status, skills etc..
Step 2 : They sent me a CodeEval challenge to complete. 4 programming questions - nothing too complex - palindrome, circular linked list, primes.. took me some 2 hours to complete (they were generous in giving 10 hours though)
Step 3 : After having complete the challenge, they scheduled a skype video screen with an engineering manager. Was relatively easy, covering general technical topics, a little bit of complexity of some algorithms and design questions.
Step 4 : They invited me for an on-site interview. The interviews were set up as panel interviews with 4 engineers asking design questions mostly (no coding) and a second panel assessing culture fit. Questions were easy and straightforward - nothing too complex [but they were looking for specific answers and not open to different ways of doing things and discussing it - red flag for me] and panel was very cold [red flag again] and did not make me feel welcome at all. All business and no fun. Anyways, perhaps it's their mandate to be serious and treat candidates very business.
Anyways, general negative experience interview experience, mostly due to the bad communications and no responsiveness or follow up after the interview.