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 a donations service with 3-day rolling totals
Design a service that ingests donations and serves rolling 3-day donation totals. Requirements Core features 1. Ingest donation events: - Each dona...
Design and explain your project architecture
Question Pick one of your recent projects and walk an interviewer through its architecture end-to-end. Sketch a high-level diagram, then go deep on th...
How do you test two variants vs control?
You ran an A/B/n experiment with 1 control and 2 treatment variants. The primary metric is conversion rate (each user either converts or not within th...
Debug and scale a PyTorch training loop
You are given a PyTorch training script for a CIFAR-10 image classifier that either: - does not converge (accuracy stays near random), or - becomes un...
Design efficient Transformer inference with KV cache
You are implementing autoregressive inference for a decoder-only Transformer. 1) Explain what the KV cache is, what tensors are cached per layer, and ...
Why do you want to join this company?
In a hiring-manager interview, you are asked: - Walk me through your past experience and the impact you’ve had. - Why do you want to join this company...
Design a chatbot fallback for unknown questions
Scenario You run a ChatGPT-like assistant. Users sometimes ask questions the model cannot answer reliably (unknown/uncertain/needs up-to-date facts). ...
Evaluate a Boolean Formula AST
Evaluate a Boolean Formula AST Evaluate a formula represented as a JSON-compatible abstract syntax tree. A formula can contain Boolean literals, integ...
Implement a hierarchical file store
This question evaluates proficiency in modeling hierarchical file systems, path parsing and manipulation, managing mutable file contents, and analyzin...
Solve two set and graph problems
Implement solutions for the following two data-structure / algorithm problems. --- Problem 1: Friend-purchase recommendations You are given three enti...
Implement a minimal local HTTP server
Build a Minimal Local HTTP/1.1 Server (No Frameworks) Context You are asked to implement a minimal HTTP/1.1 server from scratch using only the standar...
Design production-ready dedup service
System Design: Production-Ready File Deduplication Service Context Design a multi-tenant cloud service that stores files and achieves space savings vi...
Design a multi-tenant Slack-like messenger
System Design: Multi‑Tenant B2B Team Messaging (Slack‑like) Design a multi‑tenant, enterprise‑grade team messaging platform similar to Slack. Function...
Generate values by weighted probabilities
Weighted Random Sampling Generator (Streaming) You are given: - A list of distinct integers values. - A matching list of nonnegative probabilities (we...
Design distributed log storage service
Design a Distributed Append-Only Log Storage System You are asked to design the storage layer of a distributed, partitioned, replicated append-only lo...
Design a GPT chat UI with snapshots and sharing
System Design: End-to-End Web App for Interacting with a GPT-like Model Context You are designing a multi-tenant, browser-based SaaS application that ...
Calculate conditional probabilities for coin tosses
Probability with Two Fair Coin Tosses You toss a fair coin twice. Let the coin be fair (P(H) = P(T) = 1/2) and the tosses independent. (a) Compute P(s...
Design a scalable network I/O service
System Design: High-Volume Network I/O Backend (Files and Streaming) Context Design a backend service that supports millions of users uploading and do...
Test easy–medium array/string tasks
For typical easy–medium array and string problems, list the most important edge cases you would test (e.g., empty input, single element, duplicates, a...
Implement crawler and bracket validator
Implement two tasks: ( 1) Write a function crawl(start_urls, fetch, max_depth, domain_filter) that visits pages starting from the given seed URLs usin...