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
String Encoding (Length-Prefix Framing)
DSA TemplateBasic
ExploreDesign Blueprint
Thread Pool Executor
Low Level DesignAdvanced
ExploreScale Study
Design AI Agent Platform for Restaurant Ops
System DesignHard
Deep divePacket Probe
Server-Sent Events (SSE)
Networking & ProtocolsBeginner
ExploreStaff+ Prep
AI/ML System Design Interview
Staff+ InterviewExpert
ExploreKernel Dive
System Calls: User to Kernel Transition
Linux InternalsIntermediate
Deep dive
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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