CrackingWalnuts
New
Concurrency section is live
145 topics: mental models, patterns, Go, Java, Python, real-world, performance, lock-free, debugging
Today's Lineup
Pattern Pick
Kadane's Algorithm
DSA TemplateBasic
ExploreDesign Blueprint
Spreadsheet Engine
Low Level DesignAdvanced
ExploreScale Study
Design an Ad Click Aggregator
System DesignMedium
Deep divePacket Probe
UDP — When Speed Beats Safety
Networking & ProtocolsBeginner
ExploreStaff+ Prep
Legacy System Modernization
Staff+ InterviewAdvanced
ExploreKernel Dive
OOM Killer & Memory Pressure
Linux InternalsIntermediate
Deep dive
System Design: Maps Platform (Navigation, Routing, and Map Rendering)
Design a maps platform serving 1B daily users with real-time routing, tile rendering, traffic overlays, and offline navigation.
Read article
System Design··79 min
Explore
DSA Templates
50Algorithm 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
Concurrency
145Threads, channels, async, locks in Java + Python + Go
Distributed Systems
38Consensus, replication & more
Linux Internals
84Kernel, networking & system calls
Cheat Sheets
24Quick reference cards for interviews
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System Design: GitHub (200M Repos, Git Object Storage, Sparse Trigram Code Search, Per-Job VM CI)
System Design
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System Design: Online Auction (50K Bids/sec, Effectively-Once Settlement, Anti-Sniping)
System Design
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
VPTechnical Due Diligence
“Technical due diligence should evaluate architecture, team capability, and tech debt in equal measure”
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”
800+Articles
27Interactive Tools
18Categories
6Learning Stages
Learning Path
Discover Today
VictoriaMetrics
The Prometheus long-term storage that does more with less hardware
Message Queues & Event Streaming
Decouples producers from consumers, allowing asynchronous processing and better fault tolerance
Chord & Distributed Hash Tables
A Distributed Hash Table (DHT) maps keys to nodes in a decentralized network with no central coordinator. Any node can look up any key by routing through O(log n) intermediate nodes, even in a network with millions of participants