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."
Why use the t-statistic?
This question evaluates understanding of the t-statistic as a standardized test measure connecting effect size, variance, and sample size, and probes ...
How to evaluate a similar-listing notifications feature
Question You are a Data Scientist on a US C2C marketplace app (like Facebook Marketplace) where users buy and sell second-hand products. Current produ...
Consistent Hashing Ring with Virtual Nodes for Shard Rebalancing
This question evaluates a candidate's ability to design and implement a consistent hashing ring with virtual nodes for distributing keys across shards...
Interpret a Smart Wait Launch with Conflicting Metrics
A product changes its wait-time display to show more conservative estimates. After launch, conversion falls by 5% while actual time to pickup falls by...
Design a compliant multi-tenant analytics platform
This question evaluates system design and security competencies, including multi-tenant architecture, complex authorization and attribute-based access...
Write self-attention and cross-entropy pseudocode
You are asked to explain core Transformer / deep learning components. Part A — Self-attention pseudocode Write clear pseudocode (not full code) for sc...
Design streaming mention analytics with search and alerts
This question evaluates system-design competencies such as real-time stream ingestion, stateful stream processing and time-windowed aggregation, high-...
Design a disk-backed KV store under contention
This question evaluates systems-design and concurrency engineering skills, specifically the ability to reason about durable on-disk storage, indexing ...
Explain why the t-statistic helps
Suppose you estimate an effect size \(\hat{\beta}\) in a regression model or an A/B test and compute a standard error \(SE(\hat{\beta})\). Explain why...
Design a Payment Fraud Detection Service
Design a real-time fraud detection service for a payment platform. When a user submits a payment attempt, the platform calls your service before autho...
Discuss ML Project Tradeoffs
You are interviewing for a senior machine learning role and are asked to discuss a past recommendation or prediction project in depth. Use one concret...
Define Churn and Design Onboarding Experiment
This question evaluates the ability to define and operationalize churn metrics and design rigorous controlled experiments for onboarding flows, includ...
Design a Scalable and Polite Web Crawler
Design a horizontally scalable web crawler with a durable frontier, host-level politeness, deduplication, parsing, and recrawl planning. Examine URL n...
Answer four core statistics questions
Problem set (timed) Answer the following four questions. 1) Covariance of order statistics Let \(X\) and \(Y\) be independent \(\mathrm{Unif}(0,1)\). ...
Handle traffic spikes and estimate server capacity
Scenario You are designing and operating a backend service that receives API requests from clients. Recently, the service becomes slow or times out wh...
Design guardrails and fallback for LLM reliability
This question evaluates a candidate's ability to design safety and reliability layers for LLM-driven production systems, covering guardrails, input/ou...
Design game matchmaking and waiting queue
Design a scalable game matchmaking and waiting-queue system You are designing the matchmaking system for a large real-time multiplayer game (think of ...
Compare Survey Satisfaction for New and Established Users
The interview report preserved the survey tables and the request to compare response levels for new and old users, but it explicitly noted that the in...
Solve common string and subarray problems
You are given three coding tasks: 1) Reverse a string - Input: a string s. - Output: the string with characters in reverse order. 2) Maximum sum of a ...
Design expense rules engine and return type
Design a Rules Engine for Corporate Card Expenses Context We offer a corporate credit card that employees use for business expenses. Managers set poli...