The interview process had 3 stages: programming challenge, 1hour phone interview, and a full-day on-site interview with the team which included some pair programming and design discussions.
I felt Venmo's interview was not tricky or difficult but intelligent!
For example, the programming challenge was straight forward and no specific language was required, but since there are many ways of writing software for a simple problem and I felt this was how Venmo evaluate your skill level and maturity as a sw developer.
Similarly, for the phone and on-site interview, the Venmo team took the approach of having a technical conversation with you, either in the context of designing an application or musing about sw languages, design, and methodologies. I felt this was a smart way to evaluate a candidate's depth and breadth of knowledge, compare to other companies that ask "tricky" questions just to see if you know some nifty methods in Ruby Array class.
The team at Venmo seemed genuinely enthusiastic and interested in software. Their engineers could go on musing and discussing about a particular topic even after you've answered the interview question. Again this is a contrast with other companies, where the interviewer seems uninterested and is only asking for the sake of the interview.
Overall, I felt the software team at Venmo is of a high caliber.