The position is for: Senior Fullstack/Frontend Engineer.

I just finished my Uber interview onsite, and I did not get an offer. I wonder what went wrong? I passed all their technical interview questions.

Here are the questions:

• Currency converter, given an input and a dictionary containing currency mapping, write a function that will convert a number from a currency from one to another
  What I did:
  • Clarified problems, edge cases such as backward traversal
  • Using graph traversal (DFS)
  • Multiply it for every traversal, and multiply it by 1/x for every backward currency graph traversal
  • During the interview, I always talk about my solution approach
  • Solution worked, no more questions from the interviewer. The interviewer said I did good.
• Create an autocomplete engine, that will be given input of dictionary of words and weights. After that the autocomplete must also update its weights if there is a word that user type. Autocomplete must return k most weighed words.
  What I did:
  • Clarified the problems, edge cases
  • Using trie as main data structure
  • Created an autocomplete class to do the logic with DFS to collect the words
  • During the interview, I always talk about my solution approach
  • Solution worked, no more questions from the interviewer. The interviewer gave good remarks
• Create a recursive comment system using React. A user can reply to a comment and another user can reply to that comment and so on
  What I did:
  • Clarified the problems, edge cases
  • First I created the CSS
  • Then I created the recursive React component
  • Then I create the logic to wire up buttons/inputs
  • During the interview, I always talk about my solution approach
  • Solution worked, no more questions from the interviewer. The interviewer also gave good remarks.

Here is the system design question:

• Create a calendar app
  • It wasn't as focused. I went all over the map, from backend to load balancer to database to frontend
  • I can't gauge what the interviewer think of me

And then there is behavioral question

I got a reply from the recruiter, let me post it verbatim here:

Unfortunately at this time, we will not be moving forward with an offer. The team really enjoyed your positive demeanor, thought you had great communication skills, and a well thought out process throughout the technical interviews. I am not able to share specific feedback as per company policy, but I am of course happy to jump on a call if you have any questions.

I'm just wondering what went wrong.