CI/CD Pipeline System Low-Level Design
7 min read What is a CI/CD Pipeline? CI (Continuous Integration): automatically build and test code on every commit. CD (Continuous Delivery/Deployment): automatically […] Read article
System Design
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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
Secret Manager System Low-Level Design
7 min read What is a Secret Manager? A secret manager stores and distributes sensitive credentials (API keys, database passwords, TLS certificates, OAuth Read article
System Design
Log Aggregation System Low-Level Design
6 min read What is a Log Aggregator? A log aggregator collects logs from distributed services, normalizes them, stores them for search, and Read article
System Design
Rate Limiting System Low-Level Design (Token Bucket, Leaky Bucket)
6 min read Why Rate Limiting? Rate limiting protects services from abuse, ensures fair usage, and prevents cascading failures from traffic spikes. Applied Read article
System Design
Webhook Delivery System Low-Level Design
6 min read What is a Webhook? A webhook is a user-defined HTTP callback. When an event occurs in a platform (payment succeeded, Read article
System Design
Multi-Region Architecture Low-Level Design
6 min read Why Multi-Region? Single-region deployments fail entirely during a cloud provider AZ or region outage. Multi-region provides: (1) High availability — Read article
System Design
Invoice and Billing System Low-Level Design
7 min read Requirements Generate invoices for subscriptions and one-time purchases Support multiple billing cycles: monthly, annual, usage-based Apply discounts, taxes, and proration Read article
System Design
Search Suggestions (Autocomplete) System Low-Level Design
6 min read Requirements Return top-k (k=10) query suggestions as a user types, within 100ms Suggestions ranked by search frequency or relevance score Read article
System Design
Content Feed System Low-Level Design
6 min read Requirements Generate a personalized feed of posts ranked by relevance/recency for each user Supports follow relationships: see posts from users Read article
System Design
Online Auction System Low-Level Design
7 min read Requirements Users can create auction listings with a start price, reserve price, and end time Users place bids; highest bid Read article
System Design
Location Tracking System Low-Level Design
6 min read Requirements Track real-time location of mobile assets (drivers, delivery couriers, field workers) 1M active devices sending location updates every 4 Read article
System Design
Data Pipeline System Low-Level Design
6 min read What is a Data Pipeline? A data pipeline is a sequence of data processing steps: collect → transform → store Read article
System Design
Coupon and Discount System Low-Level Design
6 min read Requirements Create and manage discount coupons (percentage, fixed amount, free shipping) Apply coupon to a cart: validate, compute discount, prevent Read article
System Design
Permission and Authorization System Low-Level Design
6 min read Permission Models Overview Three main models: ACL (Access Control List): per-resource list of who can do what. Simple, fine-grained, but Read article
System Design
Hotel Reservation System Low-Level Design
6 min read Requirements Search available rooms for a date range (check-in, check-out, guests, room type) Book a room: prevent double-booking the same Read article