PayPal Staff engineer Full Stack Interview Experience
Summary
I successfully cleared all technical rounds covering Data Structures & Algorithms, Low-Level Design, System Design, and a Specialization round for a Staff Engineer Full Stack role at PayPal. However, I did not pass the final Leadership & Behavioral round, which required more structured answers and specific examples.
Full Experience
✅ Round 1: DSA (Graphs)
- Problem: Find the nearest exit in a maze grid
- Approach: BFS traversal from entry point, handled edge detection and visited cells
- Status: Cleared
✅ Round 2: Low-Level Design (Notepad App)
- Implemented cursor operations: up, down, left, right, page up, page down
- Used doubly linked list for lines and pointers for cursor movement
- Focused on correctness and time complexity
- Status: Cleared
✅ Round 3: System Design (Distributed LRU Cache)
- Designed LRU with HashMap + Doubly Linked List
- Added distributed layer using consistent hashing
- Discussed replication, eviction, and cache invalidation strategies
- Status: Cleared
✅ Round 4: Specialization Round (Shopping Cart Design)
- Features: add/view/delete items from cart
- Handled edge cases like out-of-stock items, cart overflow, and empty cart checkout
- Covered object-oriented design and basic validations
- Status: Cleared
❌ Round 5: Leadership & Behavioral
Questions around:
- Analyzing client feature requests
- Calculating ROI
- Innovation and responsibilities in current role
- End-to-end feature planning
- Giving/receiving constructive feedback
Missed out due to lack of structured answers and specific examples
Takeaway:
Strong performance in DSA, LLD, and System Design
Prepare leadership rounds with structured frameworks (e.g., STAR) and real stories
Status: Cleared all technical rounds, didn’t make it past the final leadership round. Learned a lot!
Interview Questions (9)
Find Nearest Exit in Maze Grid
Given a maze grid, find the nearest exit.
Low-Level Design: Notepad App
Design a Notepad application, specifically implementing cursor operations such as up, down, left, right, page up, and page down. Focus on correctness and time complexity.
System Design: Distributed LRU Cache
Design a Distributed LRU Cache, including discussions on replication, eviction, and cache invalidation strategies.
Shopping Cart Design
Design a shopping cart with features to add, view, and delete items. Handle edge cases like out-of-stock items, cart overflow, and empty cart checkout. Focus on object-oriented design and basic validations.
Analyzing Client Feature Requests
Questions around analyzing client feature requests.
Calculating ROI
Questions around calculating Return on Investment (ROI).
Innovation and Responsibilities
Questions around innovation and responsibilities in current role.
End-to-End Feature Planning
Questions around end-to-end feature planning.
Giving/Receiving Constructive Feedback
Questions around giving/receiving constructive feedback.
Preparation Tips
To improve, I should prepare leadership rounds with structured frameworks (e.g., STAR) and real stories.