System Design - distributed-systems
#01 Scalability

Build Meta's Notification Delivery System Premium

Design a notification platform that routes alerts across push, in-app, SMS, and email channels, handles traffic spikes of 10x during viral events, and respects per-user notification preferences in real-time.

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#02 Distributed Systems

Build a Multi-Region Config Management System Premium

Design a configuration management system that propagates changes to 20 global regions in under 500ms, prevents config divergence between regions, and supports instant rollback when a bad config causes elevated error rates.

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#03 Caching

Build Netflix's Content Delivery Network Premium

Design a CDN that caches the right content at the right PoP before users request it, handles cache misses without hitting origin, and evicts stale content across 200+ edge locations globally.

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#04 Distributed Systems

Build a Payment Processing System with Idempotency Guarantees Premium

Design a payment system that safely retries failed transactions without double-charging users, handles partial failures across payment provider integrations, and maintains a consistent ledger under concurrent requests.

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#05 Reliability

Build a Push Notification Routing System Premium

Design a notification dispatch system that routes messages across APNs, FCM, and Web Push, guarantees at-least-once delivery with deduplication, and handles delivery failures with smart retry strategies.

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#06 Performance

Build a Real-Time Fraud Detection Engine Premium

Design a fraud detection system that evaluates every payment transaction in under 100ms using behavioral, velocity, and network signals, updates risk models continuously, and minimizes false positives that block legitimate users.

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#07 Observability

Build a Real-Time Log Aggregation Pipeline Premium

Design a log ingestion and querying system that handles 1 million events per second, supports full-text search with sub-second latency, and retains 90 days of logs without breaking the budget.

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#08 Distributed Systems

Build a Schema Registry for Event-Driven Systems Premium

Design a schema registry that enforces backward and forward compatibility for Kafka topics, prevents breaking changes from reaching production, and lets consumers evolve independently of producers.

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#09 Security

Build a Secrets Management Vault Premium

Design a secrets store that encrypts credentials at rest and in transit, supports auto-rotation of API keys and DB passwords, and provides a full audit trail of every secret access.

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#10 Distributed Systems

Build Slack's Channel Message Fan-Out and Unread Counts Premium

Design a messaging system that delivers channel messages to thousands of members in a large workspace, maintains accurate unread counts per user per channel, and syncs read state across multiple devices.

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