Expedia Sr SDE US — behavioral, Java, coding, architecture

Here's my experience of virtual onsite that I gave recently.

Interview 1 [45 min]
Behavioral round with Director. Interviewer asked me to answer in STAR format.

1. Innovative task that I worked on? What was innovative?
2. When was the time that I took risk? Did it pay off?
3. When was the time that I showed a growth mindset? Challenged myself to learn something new.

Interview 2 [45 min]
Technical round with EM. Mostly Java based questions.

1. Languages I'm comfortable with.
2. Java8 vs previous versions. What's new in Java8?
3. Abstract classes
4. Dependency injection pattern vs factory builder pattern.
5. How do I monitor health of my services? Metrics, dashboards, tools.
6. How do I do integration testing? What kinds of integration testing?
7. Unit testing? Tools, frameworks.

Interview 3 [45 min]
Coding round with SDE.
https://leetcode.com/problems/integer-to-roman/ - LC medium

Interview 4 [45 min]
Architecture design - Design a hotel booking website. Mostly backend.
Tinkered with functional requirements - search, book/unbook, get bookings.
Follow-up: How would I improve architecture if I was getting booking updates from some dependency via Kafka stream.
Follow-up 2: What changes would I make to scale 10x during holiday season?

There are good YT videos on the basic template of reservation systems, watch those.
Interviewer was not helpful, and expected me to answer every ambiguity and trade-offs by myself.

Overall experience: Good, could have been great. Interviewers were not very straightforward with their answers for my questions and were very diplomatic.