It's been a minute, so please excuse any lack of specific knowledge.
Interview 1
Questions about my experience (with spring boot). What do I like about Spring boot, etc. Then, a 2sum problem, where I was asked afterwards to make unit tests for it. I finished that quickly so we talked briefly about a basic system design concept.
Interview 2
More experience questions. Not technology specific. I got asked a question where you got a list of scores (integer) on a scoreboard, sorted. Then you got a second list of scores (integer) ordered by time, and you had to return the list of what place each one would be in when inserted.
As an example, say we have a scoreboard with [5, 10, 15] and a list of scores of [6, 16, 3]:
[5, 6, 10, 15] : 3rd place
[5, 6, 10, 15, 16] : 1st place
[3, 5, 6, 10, 15, 16] : 6th place
So you'd return [3, 1, 6].
Interview 3
A basic system design question. "How would you design a product page".
Interview 4
The first half was a coding problem, a modified version of the climbing stairs problem where you output to sysout. We also talked about how I'd do automated testing of this (dependency injection). The second half was questions about core engineering principles. Stuff like "How do you descrie good code versus bad code", etc.
Offer took a while, even with prodding due to competing offers and interviews. They said it was budgeting season, which from some checking on teamblind was apparently true. Declined the offer for a FAANG offer. Was offered 25k sign on bonus.