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Backend 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 1–11 of 11 results

  • CoinbaseMediumBackend Engineer
    Implement a Stateful Trading Order Manager

    This problem tests your ability to design a stateful system using hash-based sharding, efficient indexing, and robust state machine transitions for high-frequency financial orders.

    Coding & AlgorithmsOnsiteHash TablesSystem DesignState Machines
  • HarveyMediumBackend Engineer
    Implement tag matcher and filesystem

    This combined prompt evaluates string-processing and parsing skills for tag matching and design/implementation skills for an in-memory file system, measuring competencies in exact whole-word matching, case normalization, punctuation and duplicate handling, path parsing, hierarchical data structures, and file API behaviors.

    Coding & AlgorithmsOnsite
  • MetaMediumBackend Engineer
    Solve coding and AI-assisted tasks

    This problem tests your ability to manipulate tree structures with parent pointers and verify path validity under specific movement constraints.

    Coding & AlgorithmsOnsiteTreesData StructuresAlgorithms
  • New RelicMediumBackend Engineer
    Compress a String by Run-Length Counts, Keeping the Original When Not Shorter

    Implement run-length string compression that replaces each run of repeated characters with the character and its count, returning the original string when the compressed form is not strictly shorter. Tests careful run handling, multi-digit counts, the tie rule, and complexity and edge-case discussion.

    Coding & AlgorithmsOnsite
  • New RelicMediumBackend Engineer
    Longest Strictly Increasing Path in a Grid with Four-Directional Moves

    Given an integer matrix, find the number of cells on the longest path whose values strictly increase, moving only up, down, left, or right with no diagonal steps and no wrap-around at the edges. Tests grid search and the ability to turn a working first solution into an efficient one.

    Coding & AlgorithmsOnsite
  • NuroHardBackend Engineer
    Implement BFS and a Job Scheduler

    Solve grid reveal with BFS and design a thread-safe periodic job scheduler. The solution covers Minesweeper-style expansion, queue processing, priority-queue scheduling, locks, worker pools, cancellation, duplicate prevention, long-running tasks, clock drift, and backpressure.

    Coding & AlgorithmsOnsite
  • OracleMediumBackend Engineer
    Add One to an Integer Stored as Digits Without ArrayList

    This problem tests array manipulation skills and the ability to handle carry-over logic in fixed-size numerical representations.

    Coding & AlgorithmsOnsiteArraysMathAlgorithms
  • OracleMediumBackend Engineer
    Find the Best Profit from One Stock Trade

    Tests array traversal, greedy state tracking, and achieving optimal O(n) time and O(1) space complexity for trade optimization.

    Coding & AlgorithmsOnsiteArrayDynamic ProgrammingGreedy
  • OracleMediumBackend Engineer
    Return the K Most Frequent Values with a Larger-Value Tie-Break

    This problem tests proficiency with hash maps for frequency counting and custom sorting logic using priority queues or sorting algorithms.

    Coding & AlgorithmsOnsiteHash MapSortingPriority Queue
  • OracleMediumBackend Engineer
    Split a String into Exactly Three Palindromes

    Tests string partitioning, palindrome verification, and algorithmic optimization using dynamic programming or two pointers.

    Coding & AlgorithmsOnsiteStringDynamic ProgrammingTwo Pointers
  • TeslaMediumBackend Engineer
    Compute time to burn tree

    This question evaluates proficiency with tree algorithms, distance computation, and propagation modeling, testing the ability to reason about how a process spreads across parent-child relationships in a tree.

    Coding & AlgorithmsOnsite