Katkat

practice a little every day, paws crossed ♡

Machine Learning Engineer Interview Questions

Practice 9403 coding, system design and machine learning questions from 546 companies, sorted by role, topic and interview round. Every question has step-by-step hints, a code runner that supports 8 languages and an AI mentor; members also get the full solution walkthrough.

9403
Questions
546
Companies
11
Topics
8
Languages

Showing 751–780 of 782 results

  • WaymoMediumMachine Learning Engineer
    Debug Tensor Conversion Bugs

    This question evaluates debugging and implementation-level skills in tensor and array manipulation, focusing on aliasing behavior, conversion between column lists and ndarrays, correct handling of non-divisible chunking, and writing tests for these issues.

    Coding & AlgorithmsTechnical Screen
  • WaymoMediumMachine Learning Engineer
    Design Large-Scale Inference Serving

    This question evaluates understanding of large-scale ML inference systems, assessing competencies in capacity planning, latency and tail-latency engineering, memory and bandwidth estimation, hardware selection (CPUs/GPUs/specialized accelerators), batching and caching trade-offs, and reliability concerns such as out-of-memory prevention and recovery. It is commonly asked to test practical system-design skills for production deployment by requiring back-of-the-envelope QPS and resource estimates and reasoning about operational trade-offs; this belongs to the ML system design category and emphasizes practical application over purely conceptual theory.

    ML System DesignTechnical Screen
  • WaymoHardMachine Learning Engineer
    Generate Instructions for a Blind Maze Robot

    This question evaluates a candidate's ability to design algorithmic strategies for state-space synchronization, graph traversal, and reasoning under partial observability in grid environments.

    Coding & AlgorithmsOnsite
  • WaymoMediumMachine Learning Engineer
    Optimize Tensor Runtime Kernels

    This question evaluates competency in optimizing machine learning framework runtimes for accelerators, covering profiling and performance analysis of tensor kernels, memory layout design, operator scheduling and kernel fusion while weighing trade-offs among throughput, latency, memory usage, numerical correctness, and maintainability.

    Software Engineering FundamentalsTechnical Screen
  • WaymoMediumMachine Learning Engineer
    Return All Words Matching Each Prefix From a Word List

    Build a structure over a word list that answers prefix queries, returning every distinct word that starts with each prefix in lexicographic order. Tests prefix-tree design, deduplication, and answering many queries without rescanning the whole list.

    Coding & AlgorithmsOnsite
  • WhatnotMediumMachine Learning Engineer
    Design trending livestream discovery

    This question evaluates expertise in designing end-to-end ML-driven recommendation systems, including competencies in real-time feature engineering, candidate generation, model serving, business-rule integration, monitoring, experimentation, and operational trade-offs for live content.

    ML System DesignTechnical Screen
  • WhatnotMediumMachine Learning Engineer
    Improve and debug the shopping app

    This question evaluates product-minded engineering competencies including product intuition, user-experience assessment, telemetry-driven diagnostics, funnel and segmentation analysis, and debugging/observability skills relevant to a machine learning engineer.

    System DesignTechnical Screen
  • XPengHardMachine Learning Engineer
    Design and train a PPO pipeline

    This question evaluates proficiency in designing and training Proximal Policy Optimization (PPO) pipelines, covering environment interfacing, observation/action design, reward shaping, rollout and advantage estimation, hyperparameterization, normalization, parallelization, evaluation, and sim‑to‑real considerations.

    ML System DesignTechnical Screen
  • XPengMediumMachine Learning Engineer
    Discuss resume and company fit

    This question evaluates a candidate's competence in reinforcement learning and production-grade ML systems, focusing on technical decision-making, measurable project impact, communication of role and motivation, and leadership in planning within the Behavioral & Leadership domain.

    Behavioral & LeadershipTechnical Screen
  • XPengHardMachine Learning Engineer
    Explain PPO and Transformer basics

    This question evaluates mastery of reinforcement learning algorithms (PPO, policy gradients, TRPO), value-function theory and actor–critic methods (Bellman equations), on- versus off-policy trade-offs and training-stability techniques (clipping, entropy, advantage estimation), plus sequence-modeling fundamentals with Transformers (self-attention, positional encodings and complexity comparisons). It is commonly asked to judge reasoning about algorithmic trade-offs, sample efficiency and stability in practical ML systems, and falls under the Machine Learning domain—specifically reinforcement learning and deep learning/sequence modeling—testing both conceptual understanding and practical application.

    Machine LearningTechnical Screen
  • XometryMediumMachine Learning Engineer
    Explain an End-to-End ML Project

    This question evaluates leadership and end-to-end machine learning skills, including problem framing, metric definition, data handling, model selection, training and validation practices, deployment engineering, and measurement of business impact.

    Machine LearningTechnical Screen
  • XometryMediumMachine Learning Engineer
    Optimize Model Serving Under 200ms

    This question evaluates competency in deploying and optimizing machine learning models for low-latency online inference, covering model serving, latency profiling, hardware considerations, and managing accuracy–latency trade-offs within a 200ms SLO in the ML System Design domain.

    ML System DesignTechnical Screen
  • YahooEasyMachine Learning Engineer
    ML Concepts: Overfitting, Bias-Variance Trade-off, Class Imbalance, Missing Data

    A machine learning fundamentals round covering overfitting and underfitting, the bias-variance trade-off, class imbalance, and missing data. It tests whether a candidate can define each concept precisely, diagnose it from training and validation evidence, and choose remedies while weighing their side effects.

    Machine LearningTechnical Screen
  • YahooEasyMachine Learning Engineer
    Rank Items by Dot-Product Similarity to a User Embedding, Excluding Seen Items

    Rank candidate items for a user by the dot product of the user's embedding with each item's embedding, returning item indices from highest to lowest score with ties broken by index. A follow-up removes items the user has already seen, testing vectorized scoring, sorting and filtering.

    Coding & AlgorithmsTechnical Screen
  • ZillowMediumMachine Learning Engineer
    Explain why LLMs produce hallucinations

    This question evaluates a candidate's understanding of the causes and mitigation of large language model hallucinations, covering competencies in probabilistic training objectives, data characteristics, model and optimization limitations, inference-time behavior, and awareness of mitigation strategies.

    Machine LearningTechnical Screen
  • ZillowMediumMachine Learning Engineer
    Implement k-th largest in a number stream

    This question evaluates proficiency with data structures and order-statistics in a streaming context, focusing on API design and time/space complexity trade-offs within the Coding & Algorithms domain.

    Coding & AlgorithmsTechnical Screen
  • ZillowMediumMachine Learning Engineer
    Implement placeholder-based pattern matcher

    Implement placeholder-based pattern matcher evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Coding & AlgorithmsTechnical Screen
  • ZiprecruiterEasyMachine Learning Engineer
    Debug Feature Updates in a Laptop Management CLI

    Implement and debug a stateful command-line interface processor that tracks device feature configurations, updates targeted laptops without state leakage across devices, and rolls back on validation failures.

    Software Engineering FundamentalsTechnical ScreenState ManagementCLIData Structures
  • ZiprecruiterEasyMachine Learning Engineer
    Find Neighboring Records by Identifier

    This question tests the ability to manage ordered sequences and perform O(log n) lookups to retrieve adjacent elements in a dataset.

    Coding & AlgorithmsTechnical ScreenBinary SearchArraysEfficiency
  • ZooxMediumMachine Learning Engineer
    Compute Roller Coaster Scores

    Tests string parsing, floating-point evaluation, conditional logic, and the implementation of an extensible rule-based scoring engine for ride telemetry.

    Coding & AlgorithmsTechnical ScreenString ParsingImplementationDesign Patterns
  • xAIHardMachine Learning Engineer
    Constant-Time Insert, Remove, and Uniform Random Sampling

    This question evaluates the ability to design a data structure that supports constant-time insertions, removals, and uniform random sampling, testing concepts such as hashing, indexed storage, and randomized selection within the coding and algorithms domain.

    Coding & AlgorithmsOnsite
  • xAIMediumMachine Learning Engineer
    Describe your research and contributions

    Describe your research and contributions evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Behavioral & LeadershipTechnical Screen
  • xAIMediumMachine Learning Engineer
    Design O(1) random-sampling set

    This question evaluates a candidate's competency in data-structure design, randomized algorithms, and algorithmic complexity analysis within the Coding & Algorithms domain, with a focus on achieving expected O(1) operations for insert, remove, and uniform sampling.

    Coding & AlgorithmsTechnical Screen
  • xAIHardMachine Learning Engineer
    Design a house-price prediction workflow

    Design a house-price prediction workflow evaluates core ML concepts, assumptions, math intuition, training/evaluation trade-offs, and practical failure modes in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Machine LearningTechnical Screen
  • xAIMediumMachine Learning Engineer
    Dynamic Batching Decode Loop for a Mock Language Model with Slot Refilling

    An LLM inference coding question: write the generation loop for a mock language model that returns one next token per sequence in a batch. Requests finish at different steps on a stop token or a max-token limit, and freed batch slots must be refilled from a waiting queue, testing state tracking and batching logic.

    Software Engineering FundamentalsOnsite
  • xAIMediumMachine Learning Engineer
    Explain Data Collection Choices and Their Impact on Downstream Model Performance

    A machine learning screening question: explain how the data for a project on your resume was collected and processed, then discuss how data choices affect performance on downstream tasks. It tests first-hand knowledge of data pipelines, causal reasoning about data quality, and how to measure data effects.

    Machine LearningOnsite
  • xAIMediumMachine Learning Engineer
    Find All Faulty GPU Nodes with Parallel Group Tests That Cannot Share Nodes

    An algorithm design question about finding every faulty GPU node when the only tool is a group test that fails if any node in the set is bad. Tests need at least two nodes and parallel tests cannot share nodes, so it tests adaptive testing strategies, identifiability, and cost in rounds and tests.

    Software Engineering FundamentalsOnsite
  • xAIHardMachine Learning Engineer
    Greedy Longest-Match Tokenizer for an LLM Data Pipeline

    This question evaluates understanding of string-processing and greedy maximal-munch tokenization, as well as competency in designing efficient prefix-matching data structures and handling large-scale text preprocessing for LLM pipelines.

    Coding & AlgorithmsOnsite
  • xAIHardMachine Learning Engineer
    Implement Distributed Matrix Multiplication

    This problem tests your ability to design a distributed matrix multiplication algorithm by partitioning large matrices across multiple worker nodes to minimize communication overhead.

    Coding & AlgorithmsTechnical ScreenDistributed SystemsLinear AlgebraParallel Computing
  • xAIHardMachine Learning Engineer
    Implement a trie-based tokenizer

    This question evaluates a candidate's competency in designing and implementing a production-grade subword tokenizer, covering trie-based longest-prefix matching, Unicode-aware text processing, normalization and casing impacts, whitespace/punctuation rules, fallback strategies, performance and memory trade-offs, versioning, and testing for edge cases. It is commonly asked in ML System Design interviews to assess practical implementation skills and conceptual trade-off reasoning for deterministic, scalable LLM preprocessing, and tests both practical application and conceptual understanding within the ML System Design domain.

    ML System DesignTechnical Screen