Meta (formerly Facebook) is one of the most interview-prepared companies in tech — millions of people know the Meta interview format and prepare specifically for it. This systematic approach can work in your favor if you match their expectations precisely. Meta hires at massive scale across Instagram, WhatsApp, Facebook, Messenger, Reality Labs, and Meta AI.
Meta Engineering Culture
- Move fast: Meta pioneered “move fast and break things” — now “move fast with stable infrastructure”; shipping velocity is valued
- Data-driven decisions: A/B testing is ubiquitous — every feature is tested; experiment infrastructure is a core competency
- Scale: 3+ billion users; systems must work at planetary scale with multi-datacenter deployments
- Open source contribution: Meta has open-sourced React, PyTorch, Llama, GraphQL, Folly, and more — engineers often contribute
Meta Interview Process (2025–2026)
- Recruiter screen (30 min): Background, role fit, timing
- Technical screen (60 min): 2 LeetCode-style problems
- Full loop (5 rounds, 1 day on-site or virtual):
- 2× Coding (2 problems each round, LeetCode medium-hard, 45 min each)
- 1× System design (large-scale distributed system, 45 min)
- 1× Behavioral (STAR format, leadership, cross-team impact)
- 1× Role-specific (ML engineers: ML system design; infra: distributed systems)
Coding at Meta — Two Problems Per Round
Meta’s coding rounds have two problems in 45 minutes. Pace yourself: ~5 min to understand and plan, ~15 min to implement, ~5 min to test for each problem. Common patterns:
Graph Problems (Very Common at Meta)
from collections import defaultdict, deque
# Classic Meta coding question: Friend circles / number of provinces
def find_num_provinces(is_connected: list) -> int:
"""
Given n cities and their connections, find number of provinces.
Province = group of directly/indirectly connected cities.
LeetCode #547 — commonly asked at Meta.
"""
n = len(is_connected)
visited = set()
provinces = 0
def dfs(city):
visited.add(city)
for neighbor, connected in enumerate(is_connected[city]):
if connected and neighbor not in visited:
dfs(neighbor)
for city in range(n):
if city not in visited:
dfs(city)
provinces += 1
return provinces
# Meta-style: social graph problems
def mutual_friends(graph: dict, user_a: str, user_b: str) -> list:
"""Find mutual friends between two users in a social graph."""
friends_a = set(graph.get(user_a, []))
friends_b = set(graph.get(user_b, []))
return list(friends_a & friends_b)
def friend_suggestions(graph: dict, user: str, depth: int = 2) -> list:
"""
Suggest friends at distance 2 (friends of friends) not already connected.
BFS approach.
"""
direct_friends = set(graph.get(user, []))
suggestions = {}
for friend in direct_friends:
for fof in graph.get(friend, []):
if fof != user and fof not in direct_friends:
suggestions[fof] = suggestions.get(fof, 0) + 1
# Sort by number of mutual connections
return sorted(suggestions.keys(), key=lambda x: suggestions[x], reverse=True)
# Test
graph = {
'Alice': ['Bob', 'Carol'],
'Bob': ['Alice', 'Dave', 'Eve'],
'Carol': ['Alice', 'Eve'],
'Dave': ['Bob'],
'Eve': ['Bob', 'Carol'],
}
print(mutual_friends(graph, 'Alice', 'Eve')) # ['Bob', 'Carol']
print(friend_suggestions(graph, 'Alice')) # ['Eve', 'Dave'] (sorted by mutuals)
Dynamic Programming (Frequently Asked)
# "Design a function to validate usernames at scale"
# Meta-style: think about the FB-scale implications
def is_valid_username(username: str) -> bool:
"""
Rules: 3-20 chars, alphanumeric + underscore, must start with letter.
Return True if valid.
"""
if not username or not (3 <= len(username) int:
"""Count paths from top-left to bottom-right moving only right/down."""
dp = [[1] * n for _ in range(m)]
for i in range(1, m):
for j in range(1, n):
dp[i][j] = dp[i-1][j] + dp[i][j-1]
return dp[m-1][n-1]
print(count_unique_paths(3, 7)) # 28
Meta System Design — Social Graph Scale
- “Design Facebook News Feed” — fanout on write vs read, EdgeRank algorithm, CDN for media, caching with Redis, push vs pull for celebrities
- “Design Instagram Stories” — 24-hour TTL, blob storage, CDN with geo-distribution, view counting at scale, creator analytics
- “Design Facebook Messenger” — WebSocket connections, message ordering, read receipts, group chats, end-to-end encryption
- “Design the Facebook social graph” — TAO (graph cache), friend of friend queries, privacy filtering, sharding by user ID
Meta Behavioral Interview (STAR Format)
Meta uses STAR (Situation, Task, Action, Result) format rigorously. Prepare 6-8 stories covering:
- Handling conflict with a teammate or manager
- A time you took ownership beyond your role
- A project where you influenced without authority
- A technical decision you made and defended under pressure
- A failure and what you learned
- Delivering impact at Meta-scale (think big)
Meta Leveling Guide
- E3 (new grad): Solve 2 medium LeetCode per round, contribute to team work
- E4 (mid-level): Lead features, 1 hard problem acceptable in coding, SD at component level
- E5 (senior): Design systems end-to-end, influence roadmap, manage ambiguity independently
- E6 (staff): Cross-functional technical leadership, multi-year vision, org-wide impact
Related Interview Guides
- System Design Interview Questions
- Graph Algorithm Interview Questions
- Dynamic Programming Interview Questions
Related System Design Interview Questions
Practice these system design problems that appear in Meta interviews:
- Design a News Feed (Facebook-style)
- System Design: Chat System (WhatsApp / Messenger Scale)
- System Design: Notification System (Push, Email, SMS)
- Design an Ad Click Aggregation System
- React Interview Questions
- System Design: Slack
Related Company Interview Guides
- Snap Interview Guide
- Apple Interview Guide 2026: iOS Systems, Hardware-Software Integration, and iCloud Architecture
- Figma Interview Guide 2026: Collaborative Editing, Graphics, and Real-Time Systems
- Scale AI Interview Guide 2026: Data Infrastructure, RLHF Pipelines, and ML Engineering
- Airbnb Interview Guide 2026: Search Systems, Trust and Safety, and Full-Stack Engineering
- Shopify Interview Guide
- System Design: Distributed Cache (Redis vs Memcached)
- System Design: Notification System (Push, Email, SMS)
- System Design: URL Shortener (TinyURL/Bitly)
- System Design: Rate Limiter
- Machine Learning System Design: Ranking and Recommendations
- System Design: Social Network at Scale
- System Design: Live Streaming Platform (Twitch)
- System Design: Ad Serving System (Google Ads / Meta Ads)
- System Design: Gaming Leaderboard and Matchmaking
- System Design: Content Delivery Network (CDN)
- System Design: Web Crawler (Google Search Indexing)
- System Design: Content Moderation System (Instagram / YouTube)
- System Design: Feature Flag System (LaunchDarkly)
- System Design: Distributed Lock Manager (Redis / Zookeeper)
- System Design: Monitoring and Observability Platform (Datadog)
- System Design: Music Streaming Service (Spotify)
- System Design: E-Commerce Platform (Amazon)
- System Design: Ticketing System (Ticketmaster)
- System Design: Video Conferencing (Zoom / Google Meet)
- System Design: Real-Time Bidding Platform
- System Design: Machine Learning Training Infrastructure
- System Design: Event Sourcing and CQRS
- System Design: GraphQL API at Scale
- System Design: Global Content Delivery and Edge Computing
- System Design: Real-Time Collaborative Editing (Google Docs)
- TypeScript Interview Questions: Types, Generics, and Advanced Patterns
- System Design: Notification System at Scale
- System Design: Social Graph and Friend Recommendations
- System Design: WebRTC and Real-Time Video Architecture
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Meta coding interviews test number theory and modular arithmetic. Review key patterns in Math and Number Theory Interview Patterns.
Meta interviews frequently ask heap problems. Review k-th largest, merge streams, and median finder in Heap and Priority Queue Interview Patterns.
Meta coding interviews test advanced graph algorithms. Review Dijkstra, topological sort, and SCC patterns in Advanced Graph Algorithm Interview Patterns.
Meta’s social and knowledge graph is a classic system design topic. Review the full design in Knowledge Graph System Design.
Meta coding interviews test advanced DP. Review space reduction, bitmask DP, and interval DP in Dynamic Programming Optimization Patterns.
Meta coding interviews include range query problems. Review segment tree and BIT patterns in Segment Tree and Fenwick Tree Patterns.
Meta coding interviews test string search algorithms. Review KMP, Rabin-Karp, and Z-algorithm in String Search Algorithm Interview Patterns.
Meta coding interviews test advanced bit manipulation. Review XOR tricks and bitmask DP in Advanced Bit Manipulation Interview Patterns.
Meta interviews test cycle detection and graph algorithms. Review directed and undirected cycle patterns in Graph Cycle Detection Interview Patterns.
Meta coding interviews heavily test 2D grid problems. Review BFS, DFS, and search patterns in Matrix and 2D Grid Interview Patterns.
See also: Sorting Algorithm Deep Dive: Quicksort, Mergesort, Heapsort, and Counting Sort
See also: Low-Level Design: Content Moderation System – Rules Engine, ML Scoring, and Appeals
Meta interviews test backtracking. Review subsets, permutations, and N-Queens patterns in Backtracking Interview Patterns.
Meta News Feed is the canonical social feed design. Review fan-out, ranking, and caching in Social Feed System Low-Level Design.
See also: Advanced Number Theory Interview Patterns: CRT, Euler Totient, and Digit DP
See also: Priority Queue and Monotonic Queue Patterns: Sliding Window, Top-K, and Scheduling
See also: Advanced Stack Interview Patterns: Monotonic Stack, Calculator, and Expression Parsing (2025)
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Meta interviews test probability reasoning. Review reservoir sampling, Bloom filters, and random algorithms in Probability and Statistics Interview Patterns.
Meta coding interviews test sliding window and BFS patterns. Review the monotonic deque and task scheduler in Queue and Deque Interview Patterns.
Meta coding interviews test range queries and BITs. Review Fenwick trees, segment trees, and sparse tables in Range Query Interview Patterns.
Meta interviews test trie problems. Review prefix search, Word Search II, and autocomplete patterns in Trie Interview Patterns.
Meta coding interviews test interval problems. Review merge, meeting rooms, and sweep line patterns in Interval Interview Patterns.
Meta coding interviews test string algorithms. Review sliding window, KMP, and rolling hash patterns in String Interview Patterns.
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Meta coding interviews test sorting. Review merge sort inversions, quickselect, and custom comparators in Sorting Algorithm Interview Patterns.
Meta tests linked list manipulation extensively. Review fast-slow pointers, reverse, and merge K lists in Linked List Interview Patterns.
Meta tests tree DP extensively. Review diameter, max path sum, House Robber III, and tree cameras in Dynamic Programming on Trees Interview Patterns.
Meta tests graph algorithms extensively. Review DFS, BFS, topological sort, and island patterns in Graph Traversal Interview Patterns.
Meta tests string DP extensively. Review LCS, edit distance, regex matching, and palindrome partitioning in Dynamic Programming on Strings Interview Patterns.
Meta tests heap patterns extensively. Review two-heap median, K-way merge, and lazy deletion in Advanced Heap Interview Patterns.
Meta tests binary search algorithms. Review binary search on answer space, rotated arrays, and 2D matrix search in Advanced Binary Search Interview Patterns.
Meta tests 2D DP patterns. Review grid paths, maximal square, dungeon game, and rolling arrays in 2D Dynamic Programming Interview Patterns.
Meta tests interval DP. Review Burst Balloons, Strange Printer, and the O(n^3) template in Dynamic Programming on Intervals Interview Patterns.
Meta tests state machine DP. Review the stock trading variants LC 121-309-714 in Stock Trading Dynamic Programming Interview Patterns.
Meta interviews test OOP design. Review Strategy, Observer, and Command patterns in Object-Oriented Design Patterns for Coding Interviews.
Meta system design covers file and media storage. Review the file storage LLD in File Storage System (Google Drive / Dropbox) Low-Level Design.
Meta system design covers social graph at billion-user scale. Review the full LLD in Social Graph System Low-Level Design.
Meta coding interviews test prefix sum patterns. Review range sum, subarray sum, and difference arrays in Prefix Sum Interview Patterns.
Meta coding interviews include number theory and combinatorics. Review the full pattern guide in Number Theory Interview Patterns.
Meta Messenger design is a core system design interview topic. Review WebSocket delivery and Cassandra storage in Messaging System (Chat) Low-Level Design.
Meta coding interviews test divide and conquer. Review merge sort, quickselect, and inversions in Divide and Conquer Interview Patterns.
Meta coding interviews test stack patterns. Review monotonic stack, histogram, and calculator patterns in Stack Interview Patterns.
Meta coding interviews test graph ordering problems. Review Kahn’s algorithm and DFS topological sort in Topological Sort Interview Patterns.
Meta coding interviews test bit tricks. Review XOR, bitmask subsets, and Brian Kernighan’s algorithm in Bit Manipulation Interview Patterns.
Meta coding interviews test two pointers. Review 3sum, sliding window, and trapping rain water in Two Pointers Advanced Interview Patterns.
Meta coding interviews test string patterns. Review polynomial hashing and Rabin-Karp in String Hashing Interview Patterns.
Meta coding interviews test sorted list and interval problems. Review ordered map patterns in Ordered Map (TreeMap / SortedList) Interview Patterns.
Meta system design covers news feed generation and ranking. Review the fan-out and Redis feed design in Content Feed System Low-Level Design.
Meta coding interviews cover greedy algorithms. Review the full greedy pattern guide in Greedy Algorithm Interview Patterns.
Meta coding interviews cover matrix traversal. Review the full pattern guide in Matrix Traversal Interview Patterns.
Meta coding interviews test median and heap problems. Review the two-heap pattern in Two Heaps Interview Pattern.
Meta system design covers identity and session management. Review the JWT and Redis session LLD in Session Management System Low-Level Design.
Meta system design covers WhatsApp and Messenger architecture. Review the WebSocket and Cassandra chat LLD in Chat System Low-Level Design (WhatsApp / Messenger).
Real-time ranking systems are covered in our Leaderboard System Low-Level Design.
A/B testing infrastructure design is covered in our A/B Testing Platform Low-Level Design.
S3 presigned URL and async media processing design is in our Media Upload Service Low-Level Design.
Notification preference system design is covered in our Notification Preferences System Low-Level Design.
Social login and OAuth authentication design is covered in our Social Login System Low-Level Design.
Image processing pipeline and CDN design is covered in our Image Processing Service Low-Level Design.
Graph algorithm patterns and templates are covered in our Graph Algorithm Patterns for Coding Interviews.
String algorithm patterns and code templates are covered in our String Algorithm Patterns for Coding Interviews.
CDN and global content delivery system design is covered in our CDN Design Low-Level Design.
Interval algorithm patterns and templates are covered in our Interval Algorithm Patterns for Coding Interviews.
Cursor and offset pagination system design is covered in our Pagination System Low-Level Design.
Consent management and privacy system design is covered in our Consent Management System Low-Level Design.
Activity feed and fan-out system design is covered in our Activity Feed System Low-Level Design.
Follow system and social graph design is covered in our Follow System Low-Level Design.
Feature flag and rollout system design is covered in our Feature Flag System Low-Level Design.
Dark mode and UI theming system design is covered in our Dark Mode System Low-Level Design.
Comments system and threaded discussion design is covered in our Comments System Low-Level Design.
Like system and social reaction design is covered in our Like System Low-Level Design.
Session management system design is covered in our User Session Management Low-Level Design.
Live comments and SSE streaming design is covered in our Live Comments System Low-Level Design.
Presence and chat status system design is covered in our Presence System Low-Level Design.
User blocking and content visibility design is covered in our User Blocking System Low-Level Design.
OAuth and identity federation design is covered in our OAuth Social Login System Low-Level Design.
News feed pagination and cursor API design is covered in our Cursor Pagination Low-Level Design.
Caching strategy and high-traffic read performance design is covered in our Caching Strategy Low-Level Design.
Push notification token management and delivery system design is covered in our Push Notification Token Management Low-Level Design.
Bloom filter and username availability design is covered in our Bloom Filter Low-Level Design.
WebSocket server and real-time messaging system design is covered in our WebSocket Server Low-Level Design.
Document collaboration and CRDT-based sync design is covered in our Document Collaboration Low-Level Design.
User presence and messaging system design is covered in our User Presence System Low-Level Design.
Content moderation and report abuse system design is covered in our Report and Abuse System Low-Level Design.
GDPR erasure and personal data anonymization design is covered in our GDPR Right to Erasure Low-Level Design.
Feature rollout and progressive delivery design is covered in our Feature Rollout System Low-Level Design.
Distributed counter and social engagement counting design is covered in our Distributed Counter Low-Level Design.
Activity feed aggregator and social timeline design is covered in our Activity Feed Aggregator Low-Level Design.
See also: User Segmentation System Low-Level Design: Rule Engine, Dynamic Segments, and Real-Time Membership
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See also: GraphQL Gateway Low-Level Design: Schema Stitching, DataLoader Batching, and Persisted Queries
See also: Chat Service Low-Level Design: Message Storage, Delivery Guarantees, and Read Receipts
See also: Video Call Service Low-Level Design: WebRTC Signaling, Media Relay, and Quality Adaptation
See also: Matchmaking Service Low-Level Design: Skill-Based Matching, Queue Management, and Lobby System
See also: Game State Synchronization Low-Level Design: Delta Updates, Reconciliation, and Lag Compensation
See also: Session Manager Low-Level Design: Token Storage, Sliding Expiry, and Concurrent Session Limits
See also: Pub/Sub Service Low-Level Design: Topic Fanout, Subscription Filters, and Dead Letter Handling
See also: Experiment Platform Low-Level Design: Multi-Armed Bandit, Holdout Groups, and Guardrail Metrics
See also: Cohort Analysis System Low-Level Design: User Grouping, Retention Funnel, and Time-Series Metrics
See also: Timeline Service Low-Level Design: Event Ordering, Cursor Pagination, and Gap Detection
See also: Activity Stream Low-Level Design: Event Schema, Aggregation, and Real-Time Push
See also: Content Classifier Low-Level Design: Multi-Label Classification, Ensemble Models, and Human Review
See also: Bot Detection Service Low-Level Design: Behavioral Signals, Fingerprinting, and Challenge Flow
See also: News Feed Aggregator Low-Level Design: Source Polling, Deduplication, and Ranking
See also: Live Scoring System Low-Level Design: Real-Time Ingestion, Score State, and WebSocket Fan-Out
See also: Media Upload Pipeline Low-Level Design: Chunked Upload, Virus Scan, and Post-Processing
See also: Friend Recommendation Service Low-Level Design: Graph-Based Signals, Ranking, and Diversity
See also: Content Moderation Pipeline Low-Level Design: Multi-Stage Detection, Appeal Flow, and Enforcement
See also: Trust and Safety Platform Low-Level Design: Signal Aggregation, Policy Engine, and Action Bus
See also: Account Integrity Service Low-Level Design: Takeover Detection, Recovery Flow, and Step-Up Auth
See also: User Profile Service Low-Level Design: Storage, Privacy Controls, and Partial Updates
See also: Review Moderation Service Low-Level Design: Automated Filtering, Human Queue, and Appeals
See also: Click Tracking Service Low-Level Design: Event Collection, Deduplication, and Attribution
See also: Content Feed Ranking Service Low-Level Design: Scoring Model, Diversity Injection, and Feedback Loop
See also: A/B Test Assignment Service Low-Level Design: Bucketing, Consistency, and Override Support
See also: Video Transcoding Pipeline Low-Level Design
See also: Comment System Low-Level Design
See also: Low Level Design: Threaded Discussion System
See also: Low Level Design: Reactions Service
See also: Low Level Design: Passkey Authentication
See also: Low Level Design: Graph-Based Recommendation Engine
See also: Low Level Design: Presence Service
See also: Low Level Design: Typing Indicator Service
See also: Poll System Low-Level Design: Duplicate Vote Prevention, Real-Time Results, and Multi-Select
See also: Low Level Design: ML Content Moderation Service
See also: Low Level Design: Collaborative Whiteboard
See also: Low Level Design: Operational Transform Sync
See also: Low Level Design: Cursor Sharing Service
See also: Low Level Design: Feature Flag Targeting Service
See also: Low Level Design: Experimentation Platform
See also: Search Autocomplete System Low-Level Design
See also: Low Level Design: Pub/Sub Messaging System
See also: Low Level Design: Experiment Framework
See also: Low Level Design: Edge Cache Service
See also: Low Level Design: Image Processing Service
See also: Low Level Design: Thumbnail Generator Service
See also: Low-Level Design: Recommendation Engine – Collaborative Filtering, Content-Based, and Hybrid (2025)
See also: Low Level Design: Social Graph Service
See also: Low Level Design: Do-Not-Disturb Service
See also: Low Level Design: File Upload Service
See also: Low Level Design: Resumable Upload Protocol
See also: Low Level Design: Cross-Datacenter Sync Service
See also: Low Level Design: Ranking System
See also: Low Level Design: Real-Time Messaging Service
See also: Low Level Design: Message Delivery Receipts Service
See also: Low-Level Design: Content Moderation System – Rules Engine, ML Scoring, and Appeals (2025)
See also: Low Level Design: Trust and Safety Platform
See also: Low Level Design: Ad Targeting Service
See also: Low Level Design: Ad Auction System
See also: Low Level Design: Ad Delivery Service
See also: URL Shortener System Low-Level Design
See also: Low Level Design: QR Code Generator Service
See also: Low Level Design: Link Analytics Service
See also: Low Level Design: Web Crawl Scheduler
See also: Low Level Design: Fan-Out Service
See also: Low Level Design: Code Review Service
See also: Low Level Design: Distributed Build System
See also: Low Level Design: Typing Indicators Service
See also: Low Level Design: Online Status Service
See also: Low Level Design: Media Storage Service
See also: Low Level Design: Photo Sharing Service
See also: Video Streaming Platform (YouTube/Netflix) Low-Level Design
See also: Low Level Design: Push Notification Service
See also: Low Level Design: In-App Notification Center
See also: Low Level Design: Video Conferencing Service
See also: Low Level Design: Screen Sharing Service
See also: Low Level Design: Collaborative Whiteboard
See also: Low Level Design: Event Analytics Pipeline
See also: Low Level Design: Funnel Analysis Service
See also: Low Level Design: Mention and @Tagging Service
See also: Low Level Design: Voting and Reaction System
See also: Link Preview Service Low-Level Design: SSRF Prevention, Open Graph Parsing, and Caching
See also: Low Level Design: User Follow / Subscribe Service
See also: Trending Topics Low-Level Design: Sliding Window Counts, Time Decay, and Top-K Computation
See also: Low Level Design: AI Content Safety Service
See also: Low Level Design: Multimodal Search Service
See also: Low Level Design: Speech-to-Text Service
See also: Low-Level Design: Online Judge System — Submission Processing, Sandboxed Execution, and Scoring
See also: Low Level Design: Crypto Exchange Order Book
See also: Low Level Design: Leaderboard Service
See also: Low Level Design: Media Upload Service
See also: Low Level Design: Thumbnail Generation Service
See also: Live Video Streaming System Low-Level Design
See also: Low Level Design: Gaming Matchmaking Service
See also: Gaming Leaderboard System Low-Level Design
See also: Low Level Design: Data Anonymization Service
See also: Contact Book Service Low-Level Design: Contact Storage, Deduplication, and Group Management
See also: Low Level Design: News Feed Service
See also: Low Level Design: Read Receipts Service
See also: Low Level Design: Image Storage Service
See also: Low Level Design: Video Processing Pipeline
See also: Low Level Design: Autocorrect Service
See also: Translation Service Low-Level Design: String Extraction, TM Lookup, and Human Review Queue
See also: Content Tagging System Low-Level Design: Normalization, Autocomplete, and Tag-Based Search