Machine Learning Engineer + Data Scientist + Software Engineer Interview Questions
Practice the exact questions companies are asking right now.
"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."
Compare list/dict; parse JSON/CSV at scale
Compare Python list and dict precisely: for append/insert/lookup/update/delete, state average and worst-case time complexity, memory implications, and...
Design a robust fraud detection system
Real-Time Card Fraud Detector — End-to-End Design Context - Fraud base rate ≈ 0.2% (severe class imbalance) - Labels arrive with a 14-day delay (e.g.,...
Analyze data duplication effects in linear regression
OLS With Duplicated Observations: Estimator, Variance, and Inference Pitfalls Context: You have the linear model y = Xβ + ε with full-rank X ∈ ℝ^{n×p}...
Diagnose a sudden metric spike or drop
Investigate a 3-Day Jump in Checkout Conversion Rate (CCR) Context On 2025-06-12, the daily Checkout Conversion Rate (CCR) increased from 3.2% to 4.5%...
Design a model for subscription adoption prediction
Predicting 60-Day Adoption of Subscription by Non-Subscription Merchants Context You need to predict which merchants who are not currently using the S...
Communicate and de-risk a non-experimental launch
Decision-to-Launch Plan After a Synthetic Control Result Context You are a data scientist who used a Synthetic Control method to estimate the causal i...
Derive expectation for two consecutive heads
Waiting Time Until First HH (Two Consecutive Heads) Setup Let T be the number of coin flips required until the pattern HH (two consecutive heads) appe...
Prevent data registration outage and reduce loss
Preventing Silent Failures in the Premium Registration Pipeline Context A premium registration pipeline silently failed for three months, causing thou...
Challenge and validate assumptions
Vegan-Burger Launch: Assumptions at Risk, Validation, Sensitivity, and Experiment Plan Background You are evaluating the launch of a vegan burger acro...
Prove SQL proficiency with concrete outcomes
SQL Proficiency Self‑Assessment and Evidence (Technical Screen) Provide a concise self‑rating and concrete, real‑world examples that demonstrate your ...
Interpret A/B results for video-pin increase
A/B Test: Increasing Video Pins for New Users Context Pinterest ran an online controlled experiment on new users to increase the share of video pins i...
Enable secure offline reservation caching
System Design: Offline Caching for Reservations (PWA) Design a web application that supports offline access to reservation information. The app is a p...
Design a bus simulation metric
This question evaluates a candidate's ability to comprehend and navigate a large unfamiliar codebase, safely make targeted code changes, and design, i...
Design a Conversational AI Assistant
This question evaluates system design, distributed systems, and real-time inference-serving competencies for building large-scale conversational AI pr...
Design a low-latency RAG system
Design a Low-Latency RAG System for Customer Support Problem Statement Design a production-grade retrieval-augmented generation (RAG) system that powe...
Design a Trade Ledger Class
This question evaluates the ability to design class interfaces, choose and justify data structures for ordered storage, and reason about sorting behav...
Design a system for LinkedIn Skills
Design an ML system for “LinkedIn Skills”. The system should infer and/or recommend skills for members, and support downstream use cases like search/r...
Design LinkedIn Learning course recommendations
Design a mini ML system to recommend LinkedIn Learning courses to a user. Product goal: - Recommend courses that help the user succeed in their job se...
Diagnose Low CTR in an Advertising Campaign Funnel
Diagnose Low CTR in an Advertising Campaign Funnel An analysis has flagged several ad campaigns because their click-through rate (CTR) is below the av...
Explain your biggest project with trade-offs
Behavioral interview (Amazon-style). 1) Pick the biggest/most impactful project you worked on. Explain the problem, your role, the technical design, a...