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BFS Template
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Design a Tagging System
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TCP Deep Dive
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Leading AI Transformation
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ExploreKernel Dive
Heap Allocators (malloc internals)
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DSA Templates
35Algorithm patterns & code templates
System Design
41End-to-end architecture problems
Low Level Design
90Design patterns & practical code
Key Technologies
59Deep dives into core tech
Infrastructure
35Production systems & operations
Networking & Protocols
51TCP, HTTP, TLS, DNS & more
Distributed Systems
38Consensus, replication & more
Linux Internals
84Kernel, networking & system calls
Cheat Sheets
24Quick reference cards for interviews
Recent Posts
System Design: GitHub (200M Repos, Git Object Storage, Sparse Trigram Code Search, Per-Job VM CI)
System Design
Apr 23, 2026 · 69 min
System Design: Online Auction (50K Bids/sec, Effectively-Once Settlement, Anti-Sniping)
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Apr 17, 2026 · 83 min
System Design: Job Scheduler (10M Jobs/day, DAG Dependencies, Effectively-Once Execution)
System Design
Apr 15, 2026 · 61 min
Leadership
DirectorMigration Program Management
“The last 20% of any migration contains 80% of the pain. Budget and staff for it explicitly, or it will drag on for years as a zombie project”
Org Design
EnterpriseTechnical Program Management
“You need a TPM when your Slack channels are full of 'who owns this?' questions. The role exists to create clarity across organizational seams, not to manage tasks within a single team”
530+Articles
27Interactive Tools
16Categories
6Learning Stages
Learning Path
Discover Today
Kafka Streams
A stream processing library that ships inside your JVM app, not a cluster you babysit
GitOps & Infrastructure as Code
Git as the single source of truth for both application and infrastructure config
Hybrid Logical Clocks (HLC)
HLC combines a physical timestamp with a logical counter to get the best of both worlds. Events get timestamps that are close to real wall-clock time (useful for humans and TTLs) while still maintaining the causal ordering guarantees of logical clocks