CrackingWalnuts
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Concurrency section is live
145 topics: mental models, patterns, Go, Java, Python, real-world, performance, lock-free, debugging
Today's Lineup
Pattern Pick
Binary Search
DSA TemplateBasic
ExploreDesign Blueprint
Connection Pool
Low Level DesignIntermediate
ExploreScale Study
Design a News Aggregator
System DesignMedium
Deep divePacket Probe
Proxy Protocols — Forward, Reverse & SOCKS
Networking & ProtocolsIntermediate
ExploreStaff+ Prep
Technical Vision & RFC Process
Staff+ InterviewExpert
ExploreKernel Dive
Zero-Copy Networking (sendfile, splice)
Linux InternalsAdvanced
Deep dive
Explore
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
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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Leadership
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Discover Today
Tile38
The real-time geospatial database built for tracking things that move
Istio
Istiod is the single-binary control plane that merges Pilot, Citadel, and Galley. It compiles routing rules into Envoy xDS configuration and pushes it to every sidecar over gRPC streaming.
Paxos Consensus
Paxos is the original solution to distributed consensus. Leslie Lamport published it in 1998 (written in 1990), and every consensus algorithm since then, including Raft, Zab, and Viewstamped Replication, is either a variant of Paxos or heavily influenced by it