Tower Research

Role: SDE 1 (Backend Post Trade)

College: Not Specified

Interview Date: Jan 2025

Interview Type: Full-Time

Result: Rejected

Difficulty: Not Specified

Rounds: Online Assessment + 2 Technical Rounds

Topics Asked: Data Structures, Algorithms (Graph, OOP), Operating Systems, Database Management Systems, Computer Networking, Java (Connection pooling, == vs equals, deep/shallow copy, HashMap, String immutability, memory allocation), Python (memory management, debugging, decorators), SQL injection prevention, TCP congestion control.

Experience:

This candidate's interview process for an SDE 1 (Backend Post Trade) role at Tower Research Capital began with an Online Assessment in January 2025. The online assessment, conducted on HackerRank, was 135 minutes long and comprised two coding questions and four theoretical questions. The theoretical questions covered Operating Systems, Database Management Systems, and Computer Networking. One Java-specific coding question tested Object-Oriented Programming concepts, particularly inheritance. Other theoretical topics included Python memory management, debugging (readline and readlines methods), Banker's algorithm for deadlock detection, Python decorators, SQL injection prevention, Java context, `final` keyword in Java functions, synchronized method access in multithreading, Java class execution, constructor overloading, polymorphism, and TCP congestion control.

Round 1, scheduled 3-4 days after the OA, was an hour-long session focused on Data Structures and Algorithms. The interviewer asked a graph question similar to "Max Area of Island" on LeetCode, and after discussing the approach, a modified version of the question was presented.

Round 2, scheduled 3-4 days after Round 1, lasted 45 minutes and consisted of Java-specific questions, data structure-related questions, and rapid-fire questions. Topics included connection pooling, the difference between `==` and `equals` in Java, deep and shallow copy, `HashMap` and `Map` implementation, the database connection process, String immutability in Java, Java `equals` and `hashCode` method relationship, String immutability in Python, Spring Boot and related connection classes, memory allocation for primitive types, and heap and stack memory. The candidate was ultimately rejected.