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Software 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
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- 11
- Topics
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Showing 5851–5874 of 5874 results
- xAIMediumSoftware EngineerDesign a Recoverable Iterator
Design a forward-only iterator wrapper that supports saving and restoring cursor state via checkpoints, testing buffering strategies and memory management.
Coding & AlgorithmsTechnical Screendesigndata-structuresiterators - xAIMediumSoftware EngineerDesign a Retrieval-Augmented Generation (RAG) System
This question evaluates understanding and engineering competency for retrieval-augmented generation (RAG) systems, covering offline indexing and online query planes, retrieval quality, prompt assembly, grounded generation with citations, and production monitoring; the domain is ML System Design.
ML System DesignOnsite - xAIMediumSoftware EngineerDesign a URL Shortening Service: Code Generation, Redirect Path, and Scaling
A system design question asked as a 30-minute screen with no coding: design a URL shortening service that turns long URLs into short links and redirects visitors. It tests requirement scoping, capacity estimates, collision-free code generation, a fast read path, storage, scaling and failure handling.
System DesignOnsite - xAIMediumSoftware EngineerDesign a backend for an online checkers game
This problem tests your ability to design a state-aware, real-time multiplayer system that ensures data consistency, enforces complex game rules, and manages turn-based concurrency.
System DesignOnsiteWebSocketsConcurrencyAPI Design - xAIEasySoftware EngineerDesign a multi-level API rate limiter
This question assesses the ability to design a scalable, multi-tenant rate limiting service that supports hierarchical policies and global traffic coordination.
System DesignTechnical ScreenDistributed SystemsScalabilityCaching - xAIHardSoftware EngineerDesign and Implement a URL Shortening Service
Tests your ability to design a globally distributed, highly available URL shortening service capable of handling high read/write throughput with sub-millisecond redirection latency and collision-free ID generation.
System DesignOnsitesystem-designdistributed-systemscaching - xAIMediumSoftware EngineerExplain and Implement Strings
This question evaluates understanding of string data structures, memory layout, ownership and move semantics in Rust, and algorithmic complexity related to copying and performance.
Coding & AlgorithmsTechnical Screen - xAIMediumSoftware EngineerExplain arrays and memory layout
This question evaluates understanding of arrays, their contiguous memory representation including element size, alignment and indexing arithmetic, along with time-complexity analysis for access, insertion and deletion and implications for cache locality.
Coding & AlgorithmsTechnical Screen - xAIMediumSoftware EngineerExplain process vs thread and memory-sharing risks
This question tests the conceptual understanding of process versus thread architecture and the synchronization challenges inherent in shared-memory multithreading.
Software Engineering FundamentalsTechnical ScreenOperating SystemsConcurrencyMultithreading - xAIMediumSoftware EngineerExplain strings, moves, and concurrency
This question evaluates understanding of string data structures, ownership and move semantics (including Rust-specific move behavior), and concurrency models such as threads versus asynchronous coroutines, testing competencies in memory management, performance analysis, and concurrent programming.
Coding & AlgorithmsTechnical Screen - xAIHardSoftware EngineerFind kth element and sliding-window kth in stream
This problem tests your ability to maintain order statistics in a streaming context, moving from a static selection problem to an efficient sliding-window implementation.
Coding & AlgorithmsTechnical ScreenQuickSelectHeapSliding Window - xAIMediumSoftware EngineerFlatten and unflatten nested Python structures
This problem tests recursion, type introspection, and data structure manipulation by requiring the implementation of flattening and reconstruction logic for arbitrarily nested lists and dictionaries.
Coding & AlgorithmsTechnical ScreenRecursionData StructuresSerialization - xAIMediumSoftware EngineerHow Would You Prevent Hallucinations in an LLM-Based System?
This question evaluates a candidate's understanding of hallucination in large language models, including underlying causes, detection, and system-level mitigation approaches, as well as their ability to reason about model reliability and failure modes.
Machine LearningHR Screen - xAIMediumSoftware EngineerImplement a Radix Cache for Integer Sequences
This question evaluates understanding of radix trees (prefix-compressed tries), sequence-oriented trie manipulation, and the maintenance of invariants like distinct branching and maximal compression, and belongs to the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - xAIMediumSoftware EngineerImplement a parallelized sort
This problem tests your ability to implement a parallelized version of Merge Sort using threads or a thread pool, focusing on partitioning, synchronization, and managing recursion depth.
Coding & AlgorithmsOnsiteAlgorithmsConcurrencyMerge Sort - xAIEasySoftware EngineerIn-Memory Key-Value Database with Nested Transactions
This question evaluates understanding of in-memory data structures, transactional semantics (including nested transactions), and algorithmic complexity for implementing a key-value store that supports efficient GET/SET and rollback/commit operations.
Coding & AlgorithmsOnsite - xAIMediumSoftware EngineerMake a Racy BankAccount Deposit Thread-Safe Without Editing the Class, in Python and Go
A concurrency question built around a BankAccount class whose deposit method reads the balance, sleeps, then writes it back. Candidates find every race, make deposits thread-safe through a subclass or wrapper without editing or copying the class, and carry the fix over to Go, which has no inheritance.
Software Engineering FundamentalsOnsite - xAIHardSoftware EngineerMaximize distinct values after unique ± offsets
This problem tests greedy strategy and sorting to determine the maximum possible count of distinct values in an array after applying exactly one offset from a given set of allowed integers to each element.
Coding & AlgorithmsTechnical ScreenGreedySortingCombinatorics - xAIMediumSoftware EngineerMinimum Time to Run All Jobs with a Cooldown Between Identical Jobs
This question evaluates understanding of scheduling constraints, frequency analysis, and time-complexity reasoning required to minimize total execution time under per-type cooldown restrictions.
Coding & AlgorithmsOnsite - xAIEasySoftware EngineerPhone Keypad Predictive Text Suggestions
This question evaluates understanding of string-to-digit encoding, prefix-based retrieval, and efficient preprocessing for fast query-time lookup in large dictionaries.
Coding & AlgorithmsOnsite - xAIMediumSoftware EngineerSort a Large Array Using Multiple Threads
This question evaluates understanding of concurrent programming, parallel algorithm design, sorting algorithms, and merging techniques under multi-threaded execution, focusing on thread-safety, deterministic correctness despite scheduling variability, and performance trade-offs.
Coding & AlgorithmsOnsite - xAIMediumSoftware EngineerThree Exceptional Achievements, a Recent-Projects Pitch, and a Project Deep Dive
A behavioral preparation set built around project storytelling: write three one-to-two-sentence exceptional achievements, give a five-minute overview of recent projects, and present a 30-minute project deep dive followed by detailed technical questioning. It tests concise impact, ownership and depth.
Behavioral & LeadershipOnsite - xAIMediumSoftware EngineerVersioned Key-Value Store with Nested Transactions (Begin, Commit, Rollback)
This question evaluates understanding of transactional state management, nested transactions, visibility semantics for set/delete operations, and efficient in-memory data-structure manipulation.
Coding & AlgorithmsOnsite - xAIMediumSoftware EngineerWeighted LRU Cache: Capacity Counted by Item Quantity
This question evaluates understanding of cache design and LRU eviction semantics with weighted resource accounting, plus data-structure and amortized-complexity reasoning needed to support O(1) average-time operations.
Coding & AlgorithmsOnsite
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