Braze

Got an email saying they would like to start the interview process; I took a HackerRank test (one question, medium difficulty, any language). Had trouble with the coding question and was contacted that I didn't get to the next round of the interview

Hacker rank - very simple o(n) question, sorting lists based on some pipeline. Unfortunately had to cancel onsite due to coronavirus. I heard their onsite is not that difficult, mostly algorithms questions and graphs.

OA followed by an interview with an engineer. Receive rejection 5 days later. The interviewer was kind of exhausted and reluctant to speak. He asked "how do you prove your program is correct?" multiple times and then I realized he wanted me to add