Snapchat interview questions

House Robber III

Companies: Snapchat, Microsoft

Last reported Aug 2026

Service Dependency Notification System

Given a Service Network represented as a DAG where services depend on other services, implement a notification system using FastAPI that alerts a service when…

Companies: Snapchat

Last reported Aug 2026

Design an ad click aggregator

High-volume event aggregation: duplicate delivery, hot ads, late events, fast window queries, and reconciling live counts with final billing totals.

Companies: Snapchat, Amazon, Google, Meta +4

deduplication · event-time · hot-keys · reconciliation

Last reported Jul 2026

What project are you most proud of?

Companies: Snapchat, Adyen, Amazon, Anthropic +37

Last reported Jul 2026

LRU Cache

Implement an LRUCache that supports O(1) average-time get(key) returning the value or -1 and put(key, value) which inserts or updates a key and, if capacity…

Companies: Snapchat, Adobe, Amazon, Anthropic +29

Data Structure Design · Design · Doubly-Linked List · Hash Table

Last reported Feb 2026

Design YouTube

Design a video streaming platform like YouTube where creators can upload and share videos, viewers can stream content on-demand, and users receive personalized recommendations…

Companies: Snapchat, Amazon, Axon, Datadog +4

Last reported Feb 2026

Longest Increasing Path in a Matrix

Given an m x n grid, return the length of the longest strictly increasing path you can make by moving up/down/left/right; the core challenge is…

Companies: Snapchat, Meta, Microsoft

Last reported Jan 2026

Design a short-video recommender for short-term interest

Companies: Snapchat

ML System Design · Recommendation Systems

Last reported Jan 2026

Design Twitter with shopping and product recommendations

Design a social media platform similar to Twitter but incorporating Amazon-style product features such as product recommendations, shopping integration, or e-commerce…

Companies: Snapchat, Amazon, Asana, Brex +2

Last reported Dec 2025

Stock Price Fluctuation

Design a data structure that maintains timestamp→price records which may arrive out-of-order and be corrected later, supporting efficient update(timestamp, price) and queries…

Companies: Snapchat

Last reported Dec 2025

Number of Islands

Count the number of islands (4-directionally connected components of '1's) in an m×n binary grid. This is a connected-components/flood-fill problem typically solved with…

Companies: Snapchat, Amazon, Anduril, Apple +16

Array · Breadth-First Search · Depth-First Search · Matrix

Last reported Nov 2025

Design a system which can resume videos

Design a cross-platform video streaming system that allows users to pause a video on one device and seamlessly resume playback from the same position on…

Companies: Snapchat, Netflix

Last reported Oct 2025

Max Consecutive Ones II

Given a binary array, find the maximum length of a contiguous subarray of 1s you can get by flipping at most one 0 to 1…

Companies: Snapchat, Bloomberg

Last reported Oct 2025

Design a harmful content detection system

Companies: Snapchat

ML System Design

Last reported Sep 2025

Meeting Rooms

Given a list of meeting time intervals [start, end], determine whether any two intervals overlap so a single person can attend all meetings; this is…

Companies: Snapchat, Amazon, Google, Meta +1

Last reported Apr 2025

Build Predictive Model for Product Metric: Steps Explained

Companies: Snapchat

Choose Labels and Losses for Multiple Engagement Outcomes

Companies: Snapchat

Model Evaluation · Supervised Learning

Choosing Chunk Boundaries, Size and Overlap for Retrieval-Augmented Generation

Companies: Snapchat

Retrieval-Augmented Generation

Compare Batch Normalization and Layer Normalization

Companies: Snapchat

Debugging · Neural Networks & Training

Explain BatchNorm, optimizers, and L1/L2

Companies: Snapchat

ML Fundamentals · Neural Networks & Training

Explain Core ML Concepts

Companies: Snapchat, Instacart, JPMorgan

ML Fundamentals · Regression & Statistical Modeling · Supervised Learning

Explain core ML fundamentals and tradeoffs

Companies: Snapchat

ML Fundamentals · Neural Networks & Training