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."
Design cart management lifecycle service
Scenario You are designing the backend for an on-demand delivery app (restaurants and grocery). Users can create a cart, modify items from multiple de...
How to test bike delivery?
You are a data scientist at a food-delivery marketplace. The company is considering launching a bicycle courier delivery option in selected cities. De...
In-Memory Key-Value Database with Nested Transactions
This question evaluates a candidate's ability to design a data structure that layers transactional state over a committed base, testing skills in nest...
Deep Equality of Two Records
This coding question tests a software engineer's ability to implement recursive structural comparison across nested, heterogeneous data types. It eval...
Account Balance with Expiring Grants
This question evaluates the ability to design a data structure that tracks time-limited credit grants, prioritizing expiration order during spending a...
The Celebrity Problem
The Celebrity Problem At a party there are n people, labeled 0 to n - 1. Among them there may be exactly one celebrity — a person who satisfies both o...
Why Use a t-Statistic?
This question evaluates understanding of the t-statistic as a standardized measure for testing whether an estimated effect differs from zero, covering...
Design a video recommendation system
Scenario You are designing an ML-driven video recommendation product (home feed + “up next”) for a consumer app. The interviewer focuses heavily on in...
Debug and harden trial-assignment Python code
You are given the following simplified Python snippet used to assign users and trigger a 1‑month free trial: """ import random, datetime, requests def...
Design robust primary and guardrail metrics
Experiment Metric Design, Guardrails, and Power for a 14-Day A/B Test Context You are testing a newly launched, guest-facing booking feature in a glob...
Design multi-GPU matrix multiplication
Multi-GPU MatMul (2 GPUs): Design and Implementation You are given two GPUs connected via NVLink or PCIe. You must compute C = A × B where: - A is sha...
Build House Price Model Responsibly
This question evaluates a data scientist's competencies in end-to-end supervised learning pipeline design—covering train/validation/test strategy, tar...
How to rank statements by likelihood
This question evaluates proficiency in data interpretation, probabilistic reasoning, and statistical literacy for ranking statement likelihoods from v...
Boolean Expression Tree with Leaf Flips
This question evaluates a candidate's ability to work with tree data structures and apply efficient update propagation techniques. It tests practical ...
Explain variance reduction in random forests
This question evaluates understanding of variance reduction in ensemble methods, the impact of inter-tree correlation on averaged predictors, and the ...
Design a model downloader
This question evaluates a candidate's competency in ML system design and distributed systems, covering model lifecycle management, versioning, integri...
Explain Your Engineering Ownership
You are on an initial technical screening call for a Software Engineer role. Despite being an early-stage "recruiter" screen, it is unusually technica...
Prevent Duplicate Request Processing
A client accidentally sends the same network request twice, for example because the user double-clicked a button, the client retried after a timeout, ...
Explain what happens when opening a website
When a user types https://www.amazon.com into a browser and presses Enter, what happens end-to-end? Cover the major steps across the browser, DNS, TCP...
When to use a dictionary vs an array?
This question evaluates understanding of data structures—arrays/lists versus dictionaries/hash maps—focusing on access patterns, time complexity for c...