Wells Fargo · Senior — 3 rounds, Java/Spring + system design + HM, offer accepted
Background
I have 4.5 years of experience and applied for the Senior Software Engineer role through Wells Fargo's career portal. There were three rounds in total.
Round 1 — Online Assessment (HackerRank)
A 90-minute HackerRank round covering:
- Java Spring Boot backend development
- SQL
- Kafka
- Microservices knowledge
This was a well-composed round. Organisations are increasingly shifting to this type of test away from typical DSA questions.
Round 2 — Technical Interview (Two Senior Engineers)
The interviewers didn't introduce themselves, but I gathered one was a senior developer and the other a manager. It started with introductions, then moved to my current project and contributions.
Java & Design:
- Interface vs abstract class; feature enhancements across Java versions
- Design patterns I've implemented — heavy focus on Bridge design pattern since I mentioned it
- SOLID principles
Spring & Infrastructure:
- Lots of questions around Spring Security
- Full CI/CD pipeline walkthrough of my current project
Kafka:
- Topics, partitions, brokers, and message ordering
System Design:
I was given a scenario: three existing services expose APIs; I need to build a system that calls all three, aggregates their documents, and persists the result to a DB for clients — handling failures end-to-end. I designed it covering:
- Circuit breaker pattern
- Async API calls via a central API orchestrator
- Dead letter queue
- Scaling
- CQRS pattern and DB read replicas
Round 3 — Hiring Manager Round
She asked me to walk through my current project architecture end-to-end on a whiteboard; I answered her follow-up questions.
Technical topics:
- Spring Security — interceptor vs filter, pre-auth, etc.
- Load balancer vs API gateway
- AI tools I use and where; LLM explained in layman's terms
- LLM vs RAG, fine-tuning, RAG pipeline optimisation techniques
Coding question:
Given a list of Employee POJO objects, find the maximum salary using Java Streams only.
Behavioural questions:
- What would you do if you're new to a team and the tech lead isn't helping?
- Reason for switching roles
Outcome
I was selected. I've probably forgotten a few scenario-based questions from each round, but those were straightforward.