Low Level Design: Secrets Manager
5 min read Overview A secrets manager provides secure storage, access control, and lifecycle management for credentials, API keys, and other sensitive values. […] Read article
System Design
← Tech Interview
System Design
Learn to design scalable, reliable systems that handle millions of users. System design interviews test your ability to architect real-world applications, considering tradeoffs, scalability, and best practices.
Core Topics:
Scalability: Load balancing, horizontal vs vertical scaling
Storage: Databases (SQL vs NoSQL), caching (Redis, Memcached)
Reliability: Replication, failover, disaster recovery
Performance: CDNs, caching strategies, database indexing
Common Design Questions:
Design URL shortener (bit.ly)
Design rate limiter
Design Twitter/Instagram feed
Design messaging system (WhatsApp)
Design file storage (Dropbox)
Interview Level: Senior engineers (L5+) at FAANG companies. Requires 3-5+ years experience to tackle effectively.
Preparation: Study system design patterns, understand distributed systems fundamentals, and practice mock interviews.
System Design
Low Level Design: SSH Key Rotation Service
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System Design
Low Level Design: CQRS Service
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Low Level Design: Saga Orchestrator
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System Design
Low Level Design: Schema Registry
7 min read Overview A schema registry is a centralized store for event and message schemas used in event-driven architectures. Producers register schemas Read article
System Design
Low Level Design: Metrics Pipeline
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System Design
Configuration Push Service Low-Level Design: Change Propagation, Client SDK, and Rollback
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System Design
A/B Test Assignment Service Low-Level Design: Bucketing, Consistency, and Override Support
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System Design
Feature Toggle Service Low-Level Design: Toggle Types, Evaluation Order, and Kill Switch
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System Design
Media Player Service Low-Level Design: Playback State, Resume Position, and Quality Selection
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System Design
Watchlist Service Low-Level Design: List Management, Priority Ordering, and Cross-Device Sync
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System Design
Progress Tracker Service Low-Level Design: Completion Events, Milestone Detection, and Streak Calculation
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System Design
FX Rate Service Low-Level Design: Provider Aggregation, Spread Calculation, and Stale Rate Handling
5 min read What Is an FX Rate Service? An FX rate service aggregates exchange rate quotes from multiple external providers, computes a Read article
System Design
Content Feed Ranking Service Low-Level Design: Scoring Model, Diversity Injection, and Feedback Loop
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System Design
Access Token Service Low-Level Design: JWT Signing, Key Rotation, and Claim Customization
5 min read What Is an Access Token Service? An access token service issues short-lived cryptographically signed tokens that authorize access to protected Read article