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Hudson River Trading's Interview Process (2026)

Blog / Hudson River Trading's Interview Process (2026)

The Hudson River Trading software engineer interview process is known for being technically rigorous, with a strong emphasis on algorithmic depth and low-level systems knowledge. Most candidates report moving through five main stages, though the exact structure can vary depending on which track you're interviewing for.

Application Review: An administrative screen that routes candidates into the appropriate track, typically General SWE or Core Developer, before any technical evaluation begins.
Recruiter Screen: A short call, usually around 30 minutes, covering your background, role motivation, and logistical details like location and timeline.
Online Assessment: A timed coding challenge typically delivered via HackerRank, usually featuring 3 to 4 problems that range from a warm-up to multiple LeetCode Hard equivalents.
Technical Phone Screen: A live, 60-minute coding session with an engineer in a shared editor like CoderPad, focusing on a Medium to Hard problem with emphasis on edge cases and complexity analysis.
Onsite or Virtual Onsite: A series of back-to-back rounds, generally 4 to 6 total, covering competitive programming, low-level systems, CS fundamentals, and behavioral questions.

To prepare effectively, organize your study plan around the core areas that HRT consistently tests across its rounds:

Data Structures & Algorithms (DSA): Competitive programming style problems with a focus on optimal solutions and flawless implementation.
CS Fundamentals: Deep dives into OS internals, networking, concurrency, and C++ internals.
Systems Design and Low-Level Performance: High-performance computing concepts including lock-free data structures, CPU cache effects, and kernel bypass networking.
Behavioral: Project deep-dives, technical disagreements, and ownership-focused questions.

1. Data Structures & Algorithms (DSA)HRT's coding rounds are competitive programming in style, not just standard interview prep. Expect heavy focus on graph theory (BFS, DFS, Dijkstra), dynamic programming, and string manipulation, and expect to reach the optimal solution quickly enough to handle several follow-up questions within the same session.One 2026 candidate reported a tree path problem involving minimum excluded primes, which required combining number theory with tree traversal. Problems like Maze with Portals and Longest Path With Different Adjacent Characters are representative of the graph and tree problems you may encounter.A critical piece of advice from recent candidates: flawless implementation matters as much as getting the right approach. An off-by-one error on a problem you clearly understand can still result in rejection. Start by drilling our top 100 DSA questions to build that execution reliability.For targeted topic practice, focus your time on graphs and dynamic programming, as these appear most frequently in both the online assessment and onsite coding rounds.

2. CS FundamentalsHRT has a dedicated CS Fundamentals round that acts as a real gatekeeper, something you won't find at most general tech companies. Expect deep questions on OS internals like threads versus processes and virtual memory, as well as networking topics such as how packets are routed between hubs and nodes.C++ internals come up frequently here too. Interviewers have asked candidates to explain the amortized complexity of push_back, describe memory layout, and discuss C++20 or C++23 features while also being ready to explain legacy memory management. Brush up on operating systems concepts and networking fundamentals to cover this round thoroughly.Concurrency is another area that surfaces regularly, including questions about synchronization primitives and the trade-offs between different threading models. Treat this round as seriously as the coding rounds because candidates who underestimate it often do not advance.

3. Systems Design and Low-Level PerformanceThe systems round at HRT goes well beyond typical system design interviews. Questions focus on low-latency and high-performance computing topics like lock-free data structures, NUMA awareness, CPU cache effects, and kernel bypass networking. This is where the Core Developer track in particular gets very specific.For the SWE track, you may also encounter a performance-focused coding question where you need to write C++ code that minimizes latency rather than just producing correct output. Think about how memory access patterns, cache line contention, and thread synchronization affect real-world performance.Some 2026 reports also mention a presentation or technical talk component where candidates walk through a past project or a case study solution. Reviewing our High-Level Design case studies is a good way to practice structuring and communicating technical architecture clearly under pressure.

4. BehavioralThe behavioral round at HRT is less about culture-fit platitudes and more about your ability to own technical work and navigate real disagreements. Expect questions like how you resolved a conflict with a teammate over a technical decision, or a deep-dive into the most complex system you have built.Come prepared with two or three well-developed project stories that you can discuss in detail, including the trade-offs you made and why. Using a structured approach like the STAR principle keeps your answers focused and ensures you actually answer what was asked.For broader practice on ownership and collaboration questions, the Behavioral Playbook is a solid resource to work through before your onsite.

ConclusionHRT's process is thorough and takes around one to two months from application to offer, so start your preparation early and be deliberate about covering each area. Use the recruiter screen to confirm your track and tailor your systems or algorithms prep accordingly. Follow the Hudson River Trading Interview Roadmap for a structured, step-by-step plan to work through every stage.