Roblox Interview Questions
Practice 87 real interview questions from Roblox. Covers Coding & Algorithms, Analytics & Experimentation, System Design, Data Manipulation (SQL/Python). For roles including Data Scientist, Software Engineer, Machine Learning Engineer.
"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."
Implement four DS coding tasks
You are completing a CodeSignal-style assessment (Python or R). Implement solutions for the following four independent questions. 1) Two-sample z-test...
Simulate robot path and detect boundedness
A robot starts at (0, 0) facing north on an infinite 2D plane. It executes a command string s consisting of 'G' (move forward one unit), 'L' (turn lef...
How to estimate a feature’s causal impact on time spent
You work on a Roblox-like game platform. A new product change ("feature") is rolled out and you want to estimate its causal impact on user engagement,...
Find largest digit-sum bucket size
You are given two integers low and high (inclusive). Define s(x) as the sum of the decimal digits of x. For every integer x in [low, high], place x in...
Design a scheduled payment system
System Design: Scheduled Payment Service Context You are designing a backend service that allows end users to: - Schedule a payment for a future date/...
Find most frequent call stack from logs
Given an array of log entries for a single-threaded program's function calls, each entry is either '->Name' (function entry) or '<-Name' (function exi...
Design game matchmaking and waiting queue
Design a scalable game matchmaking and waiting-queue system Context You are designing the matchmaking system for a large real-time multiplayer game. P...
Normalize features and rank logistic coefficients
You are given a binary classification training dataset: - X: a 2D array of shape (n_samples, n_features) containing numeric features. - feature_names:...
Find maximum follow depth using recursion
You are given a directed follows relationship representing a social graph: - Each record (follower_id, followee_id) means follower_id follows followee...
Apply Bayes' rule to compute posterior
A binary event \(A\) (e.g., “user is a payer” or “patient has a disease”) has prior probability \(P(A)\). You observe evidence \(B\) (e.g., a model pr...
Write SQL for influence score and follower growth
You are working on a social product with these tables: Tables / Schemas users - user_id BIGINT (PK) - created_at TIMESTAMP posts - post_id BIGINT (PK)...
Extend counter to per-client rate limiting
You are extending the recent-requests counter to support per-client rate limiting. Each request now includes a clientId identifying the caller. You mu...
Design resource loader and ROS-like pub/sub
System Design: Resource Loader and ROS-like Publish/Subscribe Context You are designing two foundational systems for a large-scale, real-time interact...
Compute DID estimate and pretrend flag
You are given three equal-length arrays describing observations from a panel-like dataset: - period[i] ∈ {0,1}: 0 = pre period, 1 = post period - trea...
Compute minimum sample size for A/B test
You are implementing a function to compute the minimum total sample size for an A/B test. You are given: - observed: a 1D array of historical/baseline...
Compute sample size and Bayes posterior
You are implementing two small statistical utilities. Part A — Power / sample size (two-sample z-test) - Input: - x: a 1D numeric array of historica...
Design a Scalable Like Counter
Design a large-scale service that stores and serves like counts for content items. Requirements: - Users can like and unlike an item. - Product pages ...
Design in-game payment wallet system
System Design: In‑Game Currency Transfers and Analytics Context You are designing the in‑game currency subsystem for an online game. Players can trans...
Compute A/B test sample size and Bayes posterior
Part A: Minimum sample size for a two-sided A/B z-test You are given: - observed: an array of numeric outcomes from historical data (use it to estimat...
Design real-time payments fraud model under constraints
Real-Time ML Policy Design: Prevent Unauthorized Purchases by Minors Context: You need to reduce unauthorized purchases by minors using their parents'...