The design library
Building blocks, complete architectures, and variations worth comparing. Search by the problem you want to solve or a component you want to understand.
Classic designOfficial
Billions of files, hundreds of petabytes, one strongly consistent tree: a namespace partitioned by directory, chunk servers, replication, repair, erasure coding. One-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
One set of tags across Jira issues, Confluence pages and Bitbucket pull requests: batch renders, tag pages that never leak, suggestions, popular tags: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
Design a team chat app like Slack: channels and DMs in real time, threads, unread counts and search. One-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
Real-time rated chess with server-validated moves, lag-compensated clocks, pairing by rating and a million watchers on one game: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
Buy the cheapest offer under a maximum price from 1,000 sellers: cached offers, coalesced quotes, a hold-order-capture saga, open requests: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
Ten charities, three days, $100 M: charge through a third-party processor exactly once, queue the broadcast spikes, keep live totals on sharded counters. One-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
Dish reviews only from customers who ordered them, votes counted from a change stream, reviews ranked by the Wilson bound, payouts made exactly once: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
A key-value store like DynamoDB, from one durable node to Paxos-replicated partitions to global tables run for thousands of tenants: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
A live TV vote at a million writes a second: spread by key, buffer in Kafka, aggregate the hot counter in two stages, shed what can wait: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
A hundred people typing in one document, every copy converging, nothing acknowledged lost: one owner per document, an op log with snapshots, and fenced failover: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
Live comments for millions of viewers: SSE streams, a Redis channel per video with co-located viewers, sampling and CDN snapshots for hot videos: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
Chat for a billion users: sockets on gateways, Redis pub/sub routing, an inbox per device, receipts, media in S3, encryption and regions: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
Record runs and rides on the phone without signal, upload each once, show them to friends and rank athletes by week, month and year: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
Stacks of nearby people in under 300 ms, 2 billion swipes a day, and a match never missed even when both like at once: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
Search a billion posts a day by keyword, newest or most liked first, with an inverted index you build yourself: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
Sync files up to 50 GB across devices: presigned multipart uploads, blocks named by hash, a journal per namespace with WebSocket hints, and cold tiers: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
A home feed for 2 billion users: fan-out on read, on write, and the hybrid for huge accounts, with precomputed feeds, cursors and hot posts: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
Seven-character codes that never clash, a billion redirects a day from three layers of cache, takedowns everywhere within a minute: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
Run 10,000 jobs a second within two seconds of their time, at least once, with retries, fairness between tenants and exactly-once effects: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
Watch prices on 500 million products with a polite crawler and a million browsers, verify what you are told, and notify subscribers within minutes of a drop: one-hour boards for junior, senior and staff, with the theory behind them.
Classic designOfficial
Count every ad click once, fast enough to chart live and exactly enough to bill. One-hour interview boards for junior, senior and staff: requirements, data layer, low-level design and what goes wrong at every component.