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 an in-memory key-value store using maps
Design a low-level key-value store library (like an embedded storage engine) under an interview constraint: you may use only map/dictionary-like data ...
Deep dive a technical project and its impact
Describe one technical project you led or significantly contributed to (DS/analytics/ML/engineering). The interviewer wants both a high-level story an...
Quant Trading Game: Expected-Value Betting and Market Making on Coins, Dice, and Cards
Quant Trading Game: Expected-Value Betting and Market Making on Coins, Dice, and Cards You are playing a live, 30-minute trading game against the inte...
Handle multicollinearity in feature selection
You are building an interpretable predictive model for an insurance company, such as a linear or logistic regression model for claim risk. Several inp...
Design a group chat system
Design a WhatsApp-like group chat system. Core features: - 1:1 and group conversations - Send/receive text messages (assume small payloads) - Group me...
Design evaluation when A/B test is impossible
This question evaluates a data scientist's competency in causal inference, observational experiment design, metric selection, and production monitorin...
Minimum Movement Cost to Segregate Binary Digits
Minimum Movement Cost to Segregate Binary Digits Given a binary string, repeatedly move a 1 to the right across adjacent 0 characters until all zeros ...
Implement a Banking System
Design and implement an in-memory banking system. All operations are processed in non-decreasing timestamp order. Account identifiers are strings. Mon...
Implement Review Content Moderation
This question evaluates a candidate's ability to implement consistent server-side content moderation and stateful persistence handling in a backend se...
Design a scalable notification system
Problem Design a notification system for a company at Airbnb-like scale that can send notifications to different user types (e.g., customers/guests, h...
Design a marketplace price tracking service
Design a large-scale product price tracking service similar to an e-commerce price monitor. Users can submit product links from a major online marketp...
Join Tables and Rank Users
You are given two analytics tables: - users(user_id, country, signup_date) - listening_events(event_id, user_id, played_at, minutes_played) Because th...
Design aggregator for multiple downstream services
This question evaluates system-design and distributed-systems skills, focusing on microservice aggregation, fan-out/fan-in concurrency, fault toleranc...
Design a high-level logging system
Design a high-level centralized logging system for a company. Assume many services (microservices, batch jobs) running across multiple hosts/container...
Design an LLM quality validation system
You are asked to design an end-to-end LLM quality validation system for a team that trains and serves large language models. The goal is to automatica...
Define and sample a truncated normal
Define the truncated normal Z | a < Z < b for Z ~ N(0,1): write the normalized pdf and cdf. Then design efficient samplers for three cases: (i) a = 1,...
Diagnose and experiment to reduce late deliveries
Two-Sided Delivery Platform: Rising Late Deliveries You are the first analyst on a two‑sided delivery platform that handles both food and parcel order...
Derive MLEs and conditional Normal distributions
Normal and Bivariate Normal: PDFs/CDFs, MLEs, Conditioning, and Unbiased Variance Setup - Let X1, …, Xn be i.i.d. Normal(μ, σ²). - Independently, let ...
Compare two stores’ profits rigorously
Prompt: 14-Day Plan to Decide Which Snack Shop Will Be More Profitable Next Quarter Context: Two snack shops operate simultaneously at a school gate. ...
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...