The interview process began with an onsite tech screen, followed by four 1:1 rounds.

Three of these technical rounds focused on coding questions, and one included a design problem.

Most of the technical problems were easy, but I didn't code as well as I could have, likely because I didn't practice whiteboard coding sufficiently.

The design round presented an interesting problem.

I will probably reapply for this position in about a year.

All interviewers were professional and well-behaved.

The overall process was smooth.

The recruiter communicated my area of weakness (coding), and I agree with their assessment.

Convert a tree to a doubly linked list.