Roblox interview questions

Showing 1–30 of 84 results

• Analyze Recent Orders Dataset with Python/pandasMedium

  This question evaluates proficiency in data manipulation and aggregation using Python/pandas, including extracting per-user maximums, computing overall summary statistics, and producing daily aggregates from time-stamped records.

  RobloxData ScientistData Manipulation (SQL/Python)Onsite
• Apply Bayes' rule to compute posteriorHard

  Evaluates understanding of Bayes’ rule and basic probability concepts—specifically computing a posterior probability P(A|B) and the marginal likelihood P(B) from a prior and likelihoods—in the Statistics & Math domain at a foundational-to-intermediate abstraction level.

  RobloxData ScientistStatistics & MathOnline Assessment
• Build a Configurable Two-Player Tic-Tac-Toe Board in ReactHard

  Tests your ability to architect a scalable, accessible React component with dynamic state, efficient win-detection logic for large grid sizes, and robust handling of prop updates.

  RobloxFrontend EngineerSoftware Engineering FundamentalsTechnical Screen
• Build an Auto-Rotating Traffic Light in Vanilla JavaScript Without a FrameworkMedium

  A frontend coding question asking for a traffic light that cycles through its colors automatically, built with plain HTML, CSS, and JavaScript and no framework. It tests state machine design, timer management and cleanup, efficient DOM updates, accessibility, and how to test time-based UI code.

  RobloxSoftware EngineerSoftware Engineering FundamentalsOnsite
• Choose best/worst actions under OA pressureMedium

  This question evaluates judgment and leadership competencies in data science — including risk assessment, stakeholder impact analysis, integrity under time pressure, and handling failing tests and collaborator input — and falls under the Behavioral & Leadership category.

  RobloxData ScientistBehavioral & LeadershipOnline Assessment
• Compare ROW_NUMBER, RANK, and DENSE_RANK for Top-k ResultsMedium

  Compare ROW_NUMBER, RANK, and DENSE_RANK with ties, exact-row limits, distinct score levels, and deterministic top-k semantics.

  RobloxData ScientistData Manipulation (SQL/Python)Technical Screen
• Compute A/B test sample size and Bayes posteriorEasy

  This question tests the ability to calculate required sample size for a frequentist A/B test using power analysis and to perform a Bayesian update for a Bernoulli process.

  RobloxData ScientistStatistics & MathOnline Assessment
• Compute ARPDAU/ARPPU by countryMedium

  This question evaluates data manipulation and analytics skills for computing user- and revenue-based metrics (ARPDAU, ARPPU), focusing on aggregation, multi-key joins, deduplication, time-window filtering, and correct revenue attribution.

  RobloxData ScientistData Manipulation (SQL/Python)Technical Screen
• Compute DID estimate and pretrend flagHard

  This Analytics & Experimentation question evaluates basic causal-inference and data-manipulation skills by requiring computation of a difference-in-differences (DID) estimate and a binary pretrend flag from panel-like arrays, at an implementation-level focused on summary statistics and edge-case handling.

  RobloxData ScientistAnalytics & ExperimentationOnline Assessment
• Compute diff-in-diff and pretrend flagEasy

  This question tests the ability to calculate a difference-in-differences (DiD) estimator for causal inference and implement a basic statistical test for pre-intervention trend divergence.

  RobloxData ScientistAnalytics & ExperimentationOnline Assessment
• Compute minimum sample size for A/B testHard

  Evaluates the ability to perform sample size and power calculations for a two-sample z-test—including estimating outcome standard deviation from historical continuous data—and is categorized under Analytics & Experimentation for a Data Scientist role at an implementation-level applied statistics abstraction.

  RobloxData ScientistAnalytics & ExperimentationOnline Assessment
• Compute sample size and Bayes posteriorHard

  This question evaluates understanding of statistical inference and probabilistic reasoning by combining a frequentist power/sample-size computation for a two-sided two-sample z-test with a basic Bayesian conditional probability calculation.

  RobloxData ScientistStatistics & MathOnline Assessment
• Count Distinct Hat Assignments and Maximize Hat PointsHard

  Count valid one-hat-per-person assignments and maximize assigned-hat points with exact counts, unique hat use, and bitmask or backtracking reasoning.

  RobloxSoftware EngineerCoding & AlgorithmsOnsite
• Data Center Rack Units: Can a Centered Equipment Bay Be Reserved?Medium

  Process an online stream of rack-unit reservations and span-availability checks over an infinite 1D coordinate line, answering each availability check with the data seen so far.

  RobloxSoftware EngineerCoding & AlgorithmsOnline Assessment
• Defend a metric choice under scrutinyMedium

  This question evaluates a Data Scientist's competency in metric selection, stakeholder communication, and experiment governance when defending a non-obvious primary metric.

  RobloxData ScientistBehavioral & LeadershipOnsite
• Define success metrics and monitoringHard

  Define success metrics and monitoring evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

  RobloxSoftware EngineerAnalytics & ExperimentationOnsite
• Demonstrate fit with quantified stories and motivationsHard

  This question evaluates a Data Scientist's behavioral and leadership competencies, including storytelling with quantified impact, ownership of technical decisions, trade-off analysis, error detection and correction, motivation, team collaboration, and end-to-end project thinking.

  RobloxData ScientistBehavioral & LeadershipTechnical Screen
• Derive variance and CTR confidence intervalsMedium

  This problem tests your understanding of statistical inference for binomial proportions, specifically calculating confidence intervals for Click-Through Rates (CTR) and understanding how to aggregate variability across multiple days.

  RobloxData ScientistStatistics & MathTechnical Screen
• Describe leading an ambiguous ads projectMedium

  This question evaluates a data scientist's end-to-end ownership, experimental and analytics skills in ads/growth contexts, including hypothesis formulation, metric and guardrail selection, trade-off reasoning, stakeholder alignment, conflict resolution, and quantifying impact.

  RobloxData ScientistBehavioral & LeadershipTechnical Screen
• Describe resolving revenue–UX metric conflictHard

  This question evaluates a data scientist's competency in metrics-driven product leadership, focusing on balancing monetization and user-experience metrics, quantitative trade-off analysis, experiment design, risk management, and cross-functional stakeholder decision-making.

  RobloxData ScientistBehavioral & LeadershipTechnical Screen
• Design Multi-Dimensional Request Rate LimitingEasy

  Design a distributed, low-latency rate limiting service capable of enforcing multi-dimensional limits (e.g., by user ID, IP address, and endpoint) across a large-scale gaming platform.

  RobloxSoftware EngineerSystem DesignTechnical Screen
• Design a Game Recommendation SystemMedium

  This problem tests your ability to design a multi-stage recommendation architecture tailored to a gaming platform, focusing on user-specific constraints like age-appropriateness and the challenges of the long-tail game distribution.

  RobloxMachine Learning EngineerML System DesignOnsite
• Design a Played-By Summary SystemHard

  Design a scalable social-proof service that tracks unique player counts per experience and computes real-time friend-intersection summaries under high write throughput and low read latency.

  RobloxSoftware EngineerSystem DesignTechnical Screen
• Design a Real-Time Shared To-Do ListMedium

  Design a real-time collaborative to-do list supporting concurrent edits, task reordering, fast write confirmations, and seamless reconnect recovery.

  RobloxSoftware EngineerSystem DesignTechnical Screen
• Design a Reusable Dropdown Menu ComponentMedium

  Tests a candidate's ability to architect a production-grade, reusable UI component library element with consideration for flexible API design, accessibility (WAI-ARIA), state management, and large dataset performance.

  RobloxFrontend EngineerSystem DesignOnsite
• Design a Scalable Like CounterMedium

  This question tests the ability to design a high-throughput, eventually consistent counting system that handles massive concurrent write volumes while maintaining low-latency read access.

  RobloxSoftware EngineerSystem DesignOnsite
• Design a Scalable Likes SystemMedium

  This question tests your ability to design a high-throughput, distributed service for tracking user engagement, focusing on write-heavy loads and read-consistency trade-offs.

  RobloxSoftware EngineerSystem DesignTechnical Screen
• Design a Static Audio Detection SystemHard

  This question evaluates system design and ML integration skills for building a scalable, reliable offline audio detection pipeline, including ingestion, preprocessing, STT and spectral feature extraction, rule-based post-processing, artifact persistence, and human-in-the-loop review within the ML system design domain.

  RobloxSoftware EngineerML System DesignOnsite
• Design a game genre classifierMedium

  This question assesses the ability to design an end-to-end multi-modal machine learning system for classifying user-generated game content based on diverse input features and real-time serving requirements.

  RobloxMachine Learning EngineerML System DesignOnsite
• Design a game recommendation modeling approachEasy

  This problem tests the ability to design an end-to-end recommendation engine for a massive-scale gaming platform, focusing on user-item interaction modeling and handling cold-start scenarios.

  RobloxSoftware EngineerML System DesignTechnical Screen