Waymo

A recruiter call, a 45-minute coding screen, then a virtual onsite of about four rounds: two coding, system design and a behavioral or hiring-manager round, often with a data fluency round. An extra round before the decision is common.

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  2D max pooling that also returns where each maximum came fromCodingImplement 2D max pooling over a grid of integers: a k by k window moves across the grid with a given stride, and each window outputs its maximum. Follow-up: for every output cell…

  Last asked Sep 2026Were you asked this too?
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  Autocomplete search bar with a hand-written debounceCodingBuild an autocomplete search bar: as the user types, show suggestions for the current text, fetched from a suggestion service. Calls must be debounced, so the service is called…

  Last asked Sep 2026Were you asked this too?
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  Count squares formed by vertical and horizontal segmentsCodingYou get a set of vertical and a set of horizontal line segments. Every point where a vertical and a horizontal segment cross or touch is an intersection. Count the squares whose…

  Last asked Sep 2026Were you asked this too?
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  Design a global caching service for small imagesSystem designDesign a global caching service for small images, backed by a single database that holds every image and is the source of truth. Cover the read path, the update path, the cache…

  Last asked Sep 2026Were you asked this too?
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  Design a matchmaking service for an online gameSystem designDesign a matchmaking service. It must let players join the queue and cancel, match two compatible players, notify both when a match is found, and deal with disconnects and…

  Last asked Sep 2026Were you asked this too?
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  Design an AI chatbot appAI systemBuild a chatbot app on top of a hosted LLM API: conversations, streamed answers, history, and per-user usage limits.

  Last asked Sep 2026Were you asked this too?
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  Filter an n-ary tree by substring and render it indentedCodingEach node of an n-ary tree has a string value and a list of children. 1. Given a search string, return the filtered tree: keep every node whose value contains the substring, plus…

  Last asked Sep 2026Were you asked this too?
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  Insert plus, times and parentheses to reach a targetCodingYou are given an equation whose left side is a sequence of non-negative integers with no operators between them, and whose right side is a target. For example: 2 3 4 = 20. Insert…

  Last asked Sep 2026Were you asked this too?
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  Is a number line fully covered after each landing point?CodingPoints land one at a time on the segment 0, 50. Each point covers the interval of length 1 centred on it (0.5 to each side), and covered parts stay covered. After each landing…

  Last asked Sep 2026Were you asked this too?
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  Link object tracks across two perception systemsCodingTwo perception systems, A and B, track the same objects around a vehicle independently, each with its own IDs, and each emits observations of its tracks over time. Implement an…

  Last asked Sep 2026Were you asked this too?
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  Project deep dive: present a project you ledBehavioralPresent a project you led in about 20 minutes: context, your role, the architecture, three hard trade-offs, metrics, cost and return, and what you would change. Then take 25…

  Last asked Sep 2026Were you asked this too?
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  Character at an index of a run-length encoded stringCodingA string is stored run-length encoded, like "B1A2E3C1" for BAAEEEC. Return the character at a given index without decoding the string. Follow-up: many queries; precompute prefix…

  Last asked Sep 2026Were you asked this too?
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  Copy a rectangle within a 2D array in placeCodingGiven a 2D array, a rectangular block (top-left corner, height, width) and a destination for its top-left corner, copy the block to the destination with O(1) extra memory. The…

  Last asked Sep 2026Were you asked this too?
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  Custom sort stringCodingGiven an order string of distinct letters and a string s, rearrange s so its letters follow the order given; letters missing from order may go anywhere. Count letters and emit…

  Last asked Sep 2026Were you asked this too?
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  Deduplicate a 256 GB file with 128 MB of memoryCodingA 256 GB file holds records, some duplicated. The machine has 128 MB of memory. Produce output that holds every distinct record exactly once. Explain the approach (for example…

  Last asked Sep 2026Were you asked this too?
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  Design an S3-like object storage systemSystem designStore trillions of objects of any size with eleven nines of durability, and serve reads and writes over an HTTP API at high throughput.

  Last asked Sep 2026Were you asked this too?
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  Design simulation infrastructure to evaluate a self-driving model on limited computeSystem designStart from an open question: how would you evaluate a self-driving model? Then design the infrastructure: running thousands of simulations when there is not enough compute…

  Last asked Sep 2026Were you asked this too?
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  Does a seven-segment display read the same rotated 180 degrees?CodingAn LED display shows a row of digits on seven-segment cells. Decide whether the display reads exactly the same after rotating it by 180 degrees. Work out which digits map to which…

  Last asked Sep 2026Were you asked this too?
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  Drive to an unseen destination without going in circlesCodingA car must reach a destination on a map it cannot see in advance. Each time it arrives at a place, it learns which directions it can continue in from there. Write the search that…

  Last asked Sep 2026Were you asked this too?
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  Lowest horizontal line that splits squares into equal areasCodingSeveral axis-aligned squares are given by their bottom-left corner and side length. Find the lowest horizontal line y = h such that the total square area below the line equals the…

  Last asked Sep 2026Were you asked this too?
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  LRU cacheCodingBuild a key-value cache with a fixed capacity that evicts the least recently used entry when it is full. get(key) returns the value or a miss, put(key, value) inserts or updates…

  Last asked Sep 2026Were you asked this too?
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  N-th number whose digits are all 3, 5 or 6CodingA good number is a positive integer whose decimal digits are all 3, 5 or 6: 3, 5, 6, 33, 35, 36, 53, ... Given n, return the n-th good number. Notice the link to counting in base…

  Last asked Sep 2026Were you asked this too?
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  Parse a raw CSV string and handle corrupted rowsCodingAnother team receives data as a raw CSV payload in one string. Write code that turns it into a data structure other teams can consume. Some rows are corrupted (wrong number of…

  Last asked Sep 2026Were you asked this too?
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  Predict the winner of a pick-from-either-end gameCodingTwo players take turns removing a number from either end of an array and adding it to their score; player 1 moves first and both play optimally. Return whether player 1 can win (a…

  Last asked Sep 2026Were you asked this too?
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  Return every word that starts with a prefixCodingBuild a structure over a word list, once, that answers many prefix queries: for a prefix, return every word in the list that starts with it, without rescanning the whole list. A…

  Last asked Sep 2026Were you asked this too?
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  Softmax cross-entropy forward and backward, then a training loopCodingImplement from scratch, with NumPy but no autograd, the forward and backward pass of a softmax layer followed by cross-entropy loss. Keep it numerically stable. Then use it in a…

  Last asked Sep 2026Were you asked this too?
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  Sort a transformed arrayCodingGiven a sorted array and the coefficients a, b, c of f(x) = ax^2 + bx + c, apply f to every element and return the results in sorted order in O(n). Use two pointers from both…

  Last asked Sep 2026Were you asked this too?
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  Is a vehicle ready to go after its maintenance events?CodingA vehicle can leave only when all its maintenance work is closed. Its log is a list of events: each opens a maintenance task of some type or ends the open task of that type…

  Last asked Sep 2026Were you asked this too?
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  Handle competing work prioritiesBehavioralTell me about a time several important pieces of work competed for your time. A good answer shows how you judged what mattered most, who you talked to, what you dropped or delayed…

  Last asked Aug 2026Were you asked this too?
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  Shortest distance from all buildingsCodingA grid has empty land, buildings and obstacles. Find the empty cell whose total walking distance to every building is smallest (moving up, down, left or right), or return -1 if no…

  Last asked Aug 2026Were you asked this too?
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  Conflict, feedback and on-call: three behavioral questionsBehavioralThree separate questions: a conflict at work and how you resolved it; a time you gave or received difficult feedback; and your on-call experience, including an incident you…

  Last asked Aug 2026Were you asked this too?
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  Design reliable command delivery between autonomous vehicles and the cloudSystem designDesign how commands are sent between the cloud and a fleet of autonomous vehicles (and acknowledgements back), so a command is delivered and acted on exactly as intended even with…

  Last asked Aug 2026Were you asked this too?
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  Design a shared-ride matching serviceSystem designDesign the service that matches riders into shared rides and runs those trips: taking requests, deciding which riders share a vehicle, planning pickups and drop-offs along the…

  Last asked Aug 2026Were you asked this too?
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  Format bytes as a hex and ASCII dumpCodingWrite a function that prints a byte buffer as a hex dump, like xxd or hexdump -C: each line shows the offset, a fixed number of bytes in hex, and the same bytes as ASCII with…

  Last asked Aug 2026Were you asked this too?
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  Design a fleet system that collects mapping dataSystem designDesign the system behind a fleet of sensor-equipped vehicles whose job is to collect data for building and refreshing maps. Cover how mapping needs (new areas, stale areas) become…

  Last asked Jun 2026Were you asked this too?
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  Find a repeating command program for a vehicle under fuel and memory limitsCodingA vehicle on a grid starts at a given cell with 100 fuel. Each move up, down, left or right costs one unit; at a station it can refuel 50 units; obstacles block movement. It can…

  Last asked Jun 2026Were you asked this too?
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  Find dictionary words that stretch into a given stringCodingA word can produce a string by repeating some of its letters in place: help can produce heellp. Given the string and a dictionary, return every dictionary word that could produce…

  Last asked Jun 2026Were you asked this too?
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  Validate a parent-child forestCodingGiven a list of parent-child pairs, decide whether they form a valid forest: no node has two parents, there are no cycles, and every tree has one root. Return the reason when it…

  Last asked May 2026Were you asked this too?
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  Best meeting point on a gridCodingA grid marks several people's (or points') positions. Find the cell that minimizes the total distance to all of them. Start with a brute force (for example a BFS from each point)…

  Last asked May 2026Were you asked this too?
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  Debug an Angular UI from user reportsCodingYou get an Angular application and a handful of user bug reports. Reproduce each problem, find the cause in the code and fix it, explaining how you narrowed it down.

  Last asked May 2026Were you asked this too?
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  Run promise tasks with bounded concurrencyCodingGiven a list of async tasks (functions returning promises) and a limit k, run them with at most k in flight at once, start the next as soon as one finishes, and resolve with all…

  Last asked May 2026Were you asked this too?
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  Decode stringCodingA string is encoded with the rule ktext, meaning text repeated k times; k is a positive integer that may have several digits, encoded parts can be nested, and plain letters can…

  Last asked May 2026Were you asked this too?
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  Design an elevator control systemOO designModel a bank of elevators: hall and car requests, a dispatching strategy, direction and door states, and capacity limits.

  Last asked Apr 2026Were you asked this too?
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  Largest axis-aligned rectangle from pointsCodingYou are given a list of distinct points on a 2D integer grid. Each point is a pair x, y. Return the largest area of a rectangle whose sides are parallel to the x and y axes and…

  Last asked Apr 2026Were you asked this too?
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  Island areas and water boundariesCodingYou are given an m x n grid of characters. Each cell is '1' (land) or '0' (water). Land cells that share a side (up, down, left or right) belong to the same island. Diagonal cells…

  Last asked Apr 2026Were you asked this too?
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  Maximum gapCodingGiven an unsorted array, return the largest difference between two neighbours in its sorted order, in linear time and space. The trick is bucket sort (pigeonhole): the maximum gap…

  Last asked Apr 2026Were you asked this too?
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  Shortest travel times from a start node to target nodesCodingA weighted graph models a road map. Given a start node and one or more target nodes, return the shortest travel time (an ETA) from the start to each target. Use Dijkstra's…

  Last asked Apr 2026Were you asked this too?
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  React Battleship boardCodingIn React, build the board for the game Battleship (just the board, no opponent logic). Each cell can be clicked to change its state (empty, hit, miss), and the board shows which…

  Last asked Apr 2026Were you asked this too?
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  Design a drop-off spot selector for a robotaxiML designDesign an ML system that picks where an autonomous ride-hail vehicle should drop off its passenger near the destination. Cover the candidate spots, the signals and labels you…

  Last asked Mar 2026Were you asked this too?
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  Serialize an expression tree with the fewest parenthesesCodingGiven a binary expression tree of numbers and operators, print it as an infix expression using only the parentheses that precedence and associativity require (for example, keep…

  Last asked Feb 2026Were you asked this too?
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  Minimum knight movesCodingOn a chess board (possibly infinite), return the fewest moves a knight needs to get from one square to another. Use BFS, and consider symmetry or bidirectional BFS to make it…

  Last asked Feb 2026Were you asked this too?
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  Python fundamentals: a Fibonacci generator, a balanced BST and frozensetCodingA set of short Python tasks: write a generator that yields the Fibonacci sequence, build a balanced binary search tree (for example from a sorted list), and explain frozenset, how…

  Last asked Feb 2026Were you asked this too?
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  Design an online experimentML designDesign an online experiment (A/B test) for a product or model change. Cover the hypothesis and metrics, randomization unit, sample size and duration, guardrail metrics, how you…

  Last asked Feb 2026Were you asked this too?
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  Jump gameCodingEach element of an array is the maximum jump length from that position. Starting at index 0, decide whether you can reach the last index. Solve it greedily in O(n) by tracking the…

  Last asked Feb 2026Were you asked this too?
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  Move instructions for a robot that cannot see the mazeCodingA robot is in a 2D maze but cannot see it. Produce the sequence of move instructions that gets it to the goal, under the rules the interviewer gives for what happens when a move…

  Last asked Jan 2026Were you asked this too?
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  Sliding-window request rate limiterCodingImplement a rate limiter that accepts at most limit requests in any window of ttl milliseconds. - allow(timestamp) is called once per incoming request. timestamp is in…

  Last asked Jan 2026Were you asked this too?
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  Design large-scale model inference serving with back-of-envelope sizingAI systemDesign an inference system for a model used by 100 million daily active users. Do the back-of-envelope estimates for memory and bandwidth, then explain how you would reduce…

  Last asked Nov 2025Were you asked this too?
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  Model compression: quantization-aware training, distillation and moreML designExplain the main ways to make a model smaller and faster for deployment: quantization (post-training versus quantization-aware training), knowledge distillation and pruning. For…

  Last asked Nov 2025Were you asked this too?
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  Average speed at a point on a road with overlapping reportsCodingA straight road is modeled as the number line from position 0 to 10^9. Vehicles send speed reports. Each report says that traffic on the half-open segment start, end) moved at…

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  Garage occupancy at every timestampCodingA parking garage records occupancy over n discrete timestamps, numbered 0 to n - 1. You get a list of parking tickets. Ticket entry, exit means one car arrived at timestamp entry…

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  Minimum workers with first-free job assignmentCodingJobs arrive as (jobid, start, end) with half-open times start, end). Workers are numbered 0, 1, 2, ... Part 1. Process jobs by start time (ties by job id). Each job goes to the…

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  Score a tile board by connected terrain regionsCodingA tile-laying board game ends when every player has filled a rectangular board. You must compute a player's final score. You are given board, a 2D list of strings with R rows and…

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