Netflix technical phone screen interview

Questions Netflix asks in this round 19

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  Key-value cache with per-entry TTLCodingImplement an in-memory key-value cache where every write gives a key, a value and a time-to-live. Once an entry's time is up it must behave as if it was never written. Support…

  Last asked Oct 2026Were you asked this too?
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  Rotating title picker for a home-page billboardCodingBuild a component that picks which title to show next in a billboard (or plays next in a playlist). Every title has a relevance score, and scores can change at any time. Each call…

  Last asked Sep 2026Were you asked this too?
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  Deduplicate titles across a home page's visible rowsCodingA home page shows rows (shelves) of titles, and only the first few titles of each row are visible on the first screen. The same title may appear in several rows. Choose what to…

  Last asked Jul 2026Were you asked this too?
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  Longest substring without repeating charactersCodingReturn the length of the longest substring with no repeated character, with a sliding window that remembers the last index of each character.

  Last asked Jul 2026Were you asked this too?
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  Transformer and attention fundamentalsML designExplain how a transformer works from the inside: how self-attention is computed, why the scores are scaled, how encoder and decoder masking differ, and what multiple heads buy…

  Last asked Sep 2026Were you asked this too?
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  Count pairs of words with no letters in commonCodingGiven a list of strings, count the pairs that share no character. Encode each string's character set as a bitmask so a pair check is one AND, then group strings by mask to avoid…

  Last asked Jul 2026Were you asked this too?
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  Longest run of identical consecutive itemsCodingGiven a sequence, such as a string or the list of shows a user watched in order, return the longest run of the same item repeated back to back: its length and the item (and its…

  Last asked Jul 2026Were you asked this too?
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  Playlist with add, remove and shuffleCodingImplement a video playlist that supports adding a title, removing a title and shuffling the order, along with playing the next title. Aim for constant-time add and remove, a fair…

  Last asked Jan 2026Were you asked this too?
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  Review a feature pipeline pull request, then serve features by freshnessML designYou are shown a pull request that changes a feature pipeline: the code that turns raw events into model features. All its tests pass. Review it live and explain what could go…

  Last asked Sep 2026Were you asked this too?
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  Parse a custom record format with mapped fieldsCodingParse records written in a custom text format: a few fixed comma-separated fields first (for example a machine code, a timestamp and two coded fields), then a free-form section of…

  Last asked Sep 2026Were you asked this too?
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  Minimum broadcast latency between citiesCodingCities are linked by network connections, each with a latency. A broadcast starts from a source city and travels along the links. Compute the shortest latency from the source to…

  Last asked Aug 2026Were you asked this too?
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  Maximum overlap of closed intervalsCodingGiven a list of closed intervals start, end (both endpoints included), return the largest number of intervals that contain one point on the number line. Two intervals that only…

  Last asked Jul 2026Were you asked this too?
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  Count words in a text streamCodingWrite a class that receives text in chunks from a stream and keeps a count of how many times each word has appeared, with a method to read the count of a word (or the most common…

  Last asked Apr 2026Were you asked this too?
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  Design a file backup systemSystem designDesign a system that backs up files from many machines and restores them on demand. You may assume basic file operations exist; focus on how backups work. Cover full versus…

  Last asked Apr 2026Were you asked this too?
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  Concurrent latency percentile trackerCodingBuild a component that records request latencies from many threads and answers percentile queries such as p50, p95 and p99. Discuss exact versus approximate approaches (sorted…

  Last asked Feb 2026Were you asked this too?
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  Design an ad audience targeting systemSystem designAdvertisers define audiences, including by uploading large lists of users, and campaigns target those audiences. Design the system that ingests audience data at scale and, when an…

  Last asked Jan 2026Were you asked this too?
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  Design a crash-resilient file systemSystem designDesign a file system that can recover file contents correctly after a crash at any moment. Cover write ordering, journaling or copy-on-write, what is guaranteed after fsync, the…

  Last asked Dec 2025Were you asked this too?
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  Thread-safe key-value storeCodingImplement an in-memory key-value store that many threads can use at once. Start with correctness, then reduce contention with finer-grained locks (striped locks or a lock per…

  Last asked Nov 2025Were you asked this too?
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  Turn dotted keys into a nested dictionaryCodingA model's weights come as a flat mapping from dotted names such as layer1.attention.query.weight to values. Convert it into a nested dictionary ({"layer1": {"attention": {"query":…

  Possibly retiredWere you asked this too?