Amazon || SDE-2 || Bangalore || Onsite || Interview Experience
Summary
I had an onsite interview experience for an SDE-2 role at Amazon in Bangalore, consisting of five rounds covering DSA, System Design (LLD and HLD), and Leadership Principles. Although I haven't received the official result, I assume a rejection based on my performance in some rounds.
Full Experience
I was contacted by a recruiter regarding onsite interviews for an SDE-2 role at Amazon. The interview process spanned two dates: July 26th, 2025, for rounds 1 and 2, and August 23rd, 2025, for rounds 3, 4, and 5. All interviews were conducted onsite.
Onsite Rounds:
Round 1 (DSA / Problem Solving):
This round was focused on Data Structures and Algorithms. I was asked to solve two problems. One of the specific questions was related to Serialize and Deserialize a Binary Tree. Additionally, there were a couple of generic Leadership Principles questions. The interviewer was an SDE-2, and I rated my performance as 3/5.
Round 2 (System Design - LLD):
This round concentrated on Low-Level System Design. I was tasked with designing a Filtering System capable of filtering files based on their size and extension. Similar to the previous round, one question on Leadership Principles was also posed. The interviewer was an SDE-2, and I felt I performed slightly better, giving myself a 3.5/5.
Round 3 (DSA / Problem Solving):
This was another DSA round, interviewed by a Sr. SDE (SDE 3). A key question involved finding K nodes in a BST closest to a target value. Beyond the technical problem, I was asked "Why Amazon?" and several other Leadership Principles questions. I felt this round went well, rating it 4/5.
Round 4 (System Design - HLD):
The focus of this round was High-Level System Design, with an SDM as the interviewer. I was asked to design a Real-time Monitoring System. Two Leadership Principles questions were also included. I felt confident about this round, rating my performance as 4/5.
Round 5 (Bar Raiser Maybe - System Design + DSA):
This final round, potentially a Bar Raiser round with a Sr. SDE (SDE 3) interviewer, combined System Design and DSA. I had to provide a High-Level Design of my Current Project. The DSA component involved the problem of finding the Median from a Data Stream. One Leadership Principle question was also part of this round. My self-verdict for this round was 3/5.
As of now, the result has not been shared by the recruiter. However, based on my average performance, especially in rounds 1, 2, and 5, I am assuming myself rejected.
Interview Questions (6)
Serialize and Deserialize Binary Tree
Design an algorithm to serialize and deserialize a binary tree. There is no restriction on how your serialization/deserialization algorithm should work. You just need to ensure that a binary tree can be serialized to a string and this string can be deserialized to the original tree structure.
Design a Filtering System
Design a Low-Level Filtering System capable of filtering files based on their size and file extension.
K Closest Elements in BST
Given a Binary Search Tree (BST), a floating-point target value, and an integer K, find K nodes in BST whose values are closest to the target.
Design a Real-time Monitoring System
Design a High-Level Real-time Monitoring System to track and report events or metrics.
Current Project HLD
Present and discuss the High-Level Design of your current project.
Find Median from Data Stream
Design a data structure that supports the following two operations: addNum(int num) and findMedian(). The findMedian operation should return the median of all numbers added so far.