Machine Learning Engineer ML System Design Interview Questions
Practice 178 real ML System Design interview questions for Machine Learning Engineer roles. From companies including OpenAI, Meta, Amazon, Snapchat, Google.

"I got asked a hardcore MCM DP question and I saw it on PracHub as well. Solved that question in 5 minutes. Without PracHub I doubt I could solve it in 5 hours. Though somehow didn't get hired, perhaps I guess I solved it too fast? /s"

"Believe me i'm a student here jn US. Recently interviewed for MSFT. They asked me exact question from PracHub. I saw it the night before and ignored it cause why waste time on random sites. I legit wanna go back and redo this whole thing if I had chance. Not saying will work for everyone but there is certainly some merit to that website. And i'm gonna use it in future prep from now on like lc tagged"

"10 years of experience but never worked at a top company. PracHub's senior-level questions helped me break into FAANG at 35. Age is just a number."

"I was skeptical about the 'real questions' claim, so I put it to the test. I searched for the exact question I got grilled on at my last Meta onsite... and it was right there. Word for word."

"Got a Google recruiter call on Monday, interview on Friday. Crammed PracHub for 4 days. Passed every round. This platform is a miracle worker."

"I've used LC, Glassdoor, and random Discords. Nothing comes close to the accuracy here. The questions are actually current — that's what got me. Felt like I had a cheat sheet during the interview."

"The solution quality is insane. It covers approach, edge cases, time complexity, follow-ups. Nothing else comes close."

"Legit the only resource you need. TC went from 180k -> 350k. Just memorize the top 50 for your target company and you're golden."

"PracHub Premium for one month cost me the price of two coffees a week. It landed me a $280K+ starting offer."

"Literally just signed a $600k offer. I only had 2 weeks to prep, so I focused entirely on the company-tagged lists here. If you're targeting L5+, don't overthink it."

"Coaches and bootcamp prep courses cost around $200-300 but PracHub Premium is actually less than a Netflix subscription. And it landed me a $178K offer."

"I honestly don't know how you guys gather so many real interview questions. It's almost scary. I walked into my Amazon loop and recognized 3 out of 4 problems from your database."

"Discovered PracHub 10 days before my interview. By day 5, I stopped being nervous. By interview day, I was actually excited to show what I knew."

"I recently cleared Uber interviews (strong hire in the design round) and all the questions were present in prachub."
"The search is what sold me. I typed in a really niche DP problem I got asked last year and it actually came up, full breakdown and everything. These guys are clearly updating it constantly."
Improve Trust in a RAG System
You own an enterprise retrieval-augmented generation system used for high-stakes document question answering, such as mortgage underwriting, legal rev...
Design a hierarchical multi-label classifier
System Design: Hierarchical Multi-Label Classifier for Noisy Taxonomy Context You have a catalog of items with hierarchical tags (e.g., Category → Sub...
Design notification and feed recommenders
Design two recommendation systems for a large visual-discovery platform: 1. Notification recommendation system: Decide whether to send a notification ...
Design a Production ML Serving System
You are given an existing ML-powered production system that serves online user requests. The interview focuses not on changing the model architecture ...
Design a RAG system end to end
Design a Retrieval‑Augmented Generation (RAG) System for Enterprise Text Context You are building a production RAG system that answers employee questi...
Design a low-latency RAG system
System Design: Production-Grade RAG for Customer Support (p99 ≤ 1.5 s) Goal Design a production-ready retrieval-augmented generation (RAG) system for ...
Design a video VLM end-to-end
Prompt: Design a video vision-language model (VLM) from scratch You are asked to design an end-to-end system to build a video vision-language model th...
Design an app-store app recommendation system
You are building an app recommendation system for a mobile app store. Goal Recommend apps to a user on surfaces such as: - Home feed / “Recommended fo...
Design a Location Recommendation System
Design a machine learning system that recommends places to a user in a maps or local-discovery product. A user opens the app and expects relevant near...
Debug online worse than offline model performance
Production ML: online performance worse than offline You launch an ML model. Offline evaluation (validation/test) looked good, but after deployment th...
Design a news feed ranking system
Design a personalized news feed recommendation system. Requirements: - Low latency serving (real-time feed generation). - Personalization using user b...
Design a CPA system for ad bidding
You are designing an ads bidding/optimization system where advertisers care about CPA (cost per acquisition). Describe how you would design a system t...
Design an enterprise RAG agent system
Design an enterprise AI assistant for internal company knowledge. The system should answer employee questions over documents such as policies, product...
Design an image/video near-duplicate detection system
Question Design a system to detect near-duplicate images/videos (e.g., reuploads, minor edits, different encodes) at large scale. Requirements - Suppo...
Design weapon-selling ad detection from posts
ML System Design: Detect weapon-selling ads from user posts You work on a platform with user-generated content (UGC): posts may include text, images, ...
Design a production RAG system
Question Design a production retrieval-augmented generation (RAG) system for enterprise document QA. Walk through the end-to-end architecture and just...
Design a real-time home feed ranker
Scenario Design a real-time home feed (e.g., social or content platform) that is responsive to user engagement. Users open the app and see a ranked li...
Design an LLM math-solving chain
Design an LLM-Based Arithmetic Solver Context You are building an LLM-driven service that answers arithmetic questions ranging from simple expressions...
Design an Enterprise Tool-Using Agent
Design an enterprise LLM agent that can use external tools to complete multi-step business tasks. Assume the agent may call tools such as document ret...
Design an HR Document AI Platform
Design an internal AI platform for a bank's HR organization. The platform should ingest HR documents such as policies, benefits guides, onboarding man...