practice a little every day, paws crossed ♡
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
- Companies
- 11
- Topics
- 8
- Languages
Showing 4021–4050 of 5874 results
- OpenAIHardSoftware EngineerImplement IP Address Arithmetic
Implement parsing, binary representation, arithmetic offsets, and canonical formatting for both IPv4 and IPv6 addresses and CIDR subnets.
Coding & AlgorithmsOnsitebit-manipulationstring-parsingnetworking - OpenAIMediumSoftware EngineerImplement IPv4 and CIDR iterators
This problem tests your ability to manipulate IP address bit-representations and implement a custom iterator to traverse all addresses within a given CIDR block.
Coding & AlgorithmsTechnical ScreenBitwiseNetworkingIterator - OpenAIMediumSoftware EngineerImplement KV store and plan type conversions
This question evaluates proficiency in designing scalable, time-versioned key-value data structures and in graph-based shortest-path planning for costed type conversions, assessing algorithmic thinking, complexity analysis, and robustness under large-scale constraints in the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - OpenAIMediumSoftware EngineerImplement KV store serialization
This question evaluates skills in binary serialization and deserialization, data encoding and layout, type tagging, endianness, checksumming, versioning for forward/backward compatibility, and algorithmic efficiency and space usage for an in-memory key-value store; it falls under the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - OpenAIMediumSoftware EngineerImplement Social Follow Recommendations
This problem tests your ability to navigate a social graph to implement a recommendation system using set operations and frequency counting.
Coding & AlgorithmsTechnical ScreenGraphHash MapSorting - OpenAIMediumSoftware EngineerImplement Social Graph Snapshot Queries
This problem tests your ability to design a query-optimized representation for a directed graph, specifically focusing on efficient retrieval of multi-hop relationships and neighbor-based ranking.
Coding & AlgorithmsTechnical ScreenGraphsAdjacency ListData Structures - OpenAIMediumSoftware EngineerImplement Three Research Coding Tasks
This problem tests fundamental understanding of numerical stability in probability, memory-efficient buffering, and greedy combinatorial optimization.
Coding & AlgorithmsHR ScreenNumerical StabilityDynamic ProgrammingStreaming Algorithms - OpenAIMediumSoftware EngineerImplement Time-Aware GPU Credit Ledger
Design an in-memory credit ledger that tracks GPU compute grants with expiration timestamps, consumes credits greedily by earliest expiration, and supports atomic deductions.
Coding & AlgorithmsTechnical ScreenHeap / Priority QueueDesignGreedy - OpenAIHardSoftware EngineerImplement a Contiguous Memory Allocator with Primitive Lists
Simulate best-fit allocation across a contiguous address range using only primitive lists and scalar state. Support splitting, exact-pointer frees, double-free rejection, deterministic tie-breaking, and coalescing adjacent free blocks across up to 10,000 operations.
Coding & AlgorithmsTechnical Screen - OpenAIMediumSoftware EngineerImplement a Distributed Rate Limiter
Implement a distributed token bucket rate limiter backed by a key-value store with optimistic concurrency control (CAS), handling clock skew, concurrent updates, and token replenishment.
Coding & AlgorithmsTechnical ScreenDistributed SystemsConcurrencyAlgorithms - OpenAIMediumSoftware EngineerImplement a GPU credit ledger with expiring grants and out-of-order operations
Implement a GPU credit ledger with grant, subtract and get-balance operations, where grants expire and spending draws from the soonest-expiring grant first. Operations can arrive out of timestamp order, and a follow-up asks how to avoid replaying the whole history from time zero on every query in production.
Software Engineering FundamentalsOnsite - OpenAIMediumSoftware EngineerImplement a GPU credit manager
This question evaluates understanding of concurrent resource management, advanced data structures for top-K and per-user queries, enforcement of caps and expirations, and algorithmic complexity guarantees while maintaining atomicity under concurrent operations.
Coding & AlgorithmsTechnical Screen - OpenAIMediumSoftware EngineerImplement a Recoverable In-Memory Key-Value Store
This problem tests your understanding of durability, logging, and data persistence in an in-memory system.
Software Engineering FundamentalsTechnical ScreenSystemsConcurrencyPersistence - OpenAIHardSoftware EngineerImplement a Set with Readable Snapshots
Design and implement a versioned set data structure that supports membership modifications, instant snapshotting, and historical point-in-time queries efficiently.
Software Engineering FundamentalsOnsiteData StructuresDesignBinary Search - OpenAIMediumSoftware EngineerImplement a Simple Memory Allocator
This question evaluates low-level memory management and allocator design skills, including block header layout, free-list/data-structure choices, pointer arithmetic, fragmentation concepts, and analysis of time/space complexity.
Software Engineering FundamentalsOnsite - OpenAIMediumSoftware EngineerImplement a fault-tolerant work queue that never loses tasks when workers fail
Implement an in-process work queue that never loses a task when the worker holding it crashes, stalls or reports an error. It tests task state tracking, detecting silent workers, rejecting late reports from workers that lost a task, bounded retries for tasks that always fail, thread safety, and deterministic tests built on an injected clock.
Software Engineering FundamentalsTechnical Screen - OpenAIMediumSoftware EngineerImplement a memory allocator with malloc/free
This question evaluates understanding of memory allocator concepts including malloc/free semantics, contiguous allocation, fragmentation handling, coalescing of adjacent free blocks, pointer validation, and data-structure choices for efficient allocation.
Coding & AlgorithmsTechnical Screen - OpenAIHardSoftware EngineerImplement a minimal reverse-mode autograd engine on PyTorch tensors
Implement the core of a PyTorch-style autograd system: a tensor wrapper that records addition, multiplication, matrix multiplication, ReLU and sum, plus a backward method that fills in gradients for every input. Tests reverse-mode differentiation, correct ordering of the backward pass, gradient accumulation for tensors used more than once, and verification against PyTorch.
Machine LearningTechnical Screen - OpenAIMediumSoftware EngineerImplement a serializable key-value store
This question evaluates competency in implementing robust serialization and in-memory data structures, covering binary format design, handling arbitrary bytes and Unicode, correctness across edge cases (empty state, large keys/values, overwrites, deletions), input validation and failure recovery, complexity analysis, and unit testing.
Coding & AlgorithmsTechnical Screen - OpenAIMediumSoftware EngineerImplement an Extensible Chatbot App
This question evaluates a candidate's ability to design extensible object-oriented systems, covering interface-based architecture, dependency injection, per-conversation state management, and decoupled dispatch logic.
Software Engineering FundamentalsTechnical Screen - OpenAIMediumSoftware EngineerImplement an IPv4 Iterator
This problem tests your ability to handle IPv4 address arithmetic, bitwise operations, and the implementation of a stateful iterator that supports bidirectional traversal and range generation from CIDR notation.
Coding & AlgorithmsOnsiteBit ManipulationIterator PatternNetworking - OpenAIMediumSoftware EngineerImplement an IPv4 Range Iterator
This problem tests your ability to manipulate 32-bit integers, understand bitwise operations, and implement a custom iterator for a contiguous range of IP addresses.
Coding & AlgorithmsTechnical ScreenBit ManipulationNetworkingIterator - OpenAIMediumSoftware EngineerImplement an expiring GPU credits ledger
This question evaluates understanding of time-based resource accounting, design of data structures for expiring balances, atomic update semantics for concurrent operations, and algorithmic time/space complexity within the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - OpenAIHardSoftware EngineerImplement an in-memory SQL-like table
This question evaluates implementation skills for an in-memory SQL-like table, focusing on data modeling with nested key-value structures, string handling, efficient lookups, and lexicographic sorting with tie-breaking.
Coding & AlgorithmsOnsite - OpenAIMediumSoftware EngineerImplement and Debug Backprop in NumPy
This question evaluates understanding of backpropagation and the chain rule, proficiency in vectorized NumPy implementation, numerical stability of softmax/cross-entropy, and competency in gradient checking and debugging of model gradients.
Machine LearningTechnical Screen - OpenAIMediumSoftware EngineerImplement delimiter-free string codec
This question evaluates a candidate's ability to design reversible string encodings that handle arbitrary characters and edge cases, testing competency in string manipulation, data serialization, and robustness.
Coding & AlgorithmsTechnical Screen - OpenAIMediumSoftware EngineerImplement expiring credit ledger
This question evaluates the ability to design efficient time-based data structures and algorithms for managing expiring credits with ordering and tie-breaking rules, testing competencies in event ordering, interval management, and retroactive update handling; it is in the Coding & Algorithms domain and emphasizes practical application of algorithmic and data-structure reasoning. It is commonly asked to verify correctness under out-of-order inserts and queries, to assess performance and complexity analysis for add/charge/get operations, and to require clear specification of time and space complexity for the proposed approach.
Coding & AlgorithmsTechnical Screen - OpenAIHardSoftware EngineerImplement follow graph with snapshots
This problem tests your ability to design a versioned, immutable, or persistent data structure that supports efficient graph modifications and point-in-time snapshot queries.
Coding & AlgorithmsTechnical ScreenPersistent Data StructuresGraphsVersion Control - OpenAIMediumSoftware EngineerImplement follow graph with snapshots and recommendations
This question evaluates design and implementation skills for mutable graph data structures with point-in-time snapshotting and recommendation ranking, testing knowledge of data structures, versioning, graph traversal, and algorithmic time/space complexity analysis.
Coding & AlgorithmsTechnical Screen - OpenAIMediumSoftware EngineerImplement in-memory DB querying
This question evaluates a candidate's competency in data structures, algorithms, and systems-level thinking for implementing query processing in an in-memory database, including projection, predicate filtering, ordering, and index design.
Coding & AlgorithmsTechnical Screen
OpenAI