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
BFS Template
DSA TemplateBasic
ExploreDesign Blueprint
Deck of Cards
Low Level DesignStarter
ExploreScale Study
Design an AI Software Engineer
System DesignHard
Deep divePacket Probe
Long Polling vs SSE vs WebSocket
Networking & ProtocolsIntermediate
ExploreStaff+ Prep
Migration Planning Interviews
Staff+ InterviewExpert
ExploreKernel Dive
Systemd Internals
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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Leadership
DirectorBuilding Technical Vision
“A good technical vision covers a 2-3 year horizon with concrete milestones every 6 months”
Org Design
GrowthEngineering Manager to IC Ratio
“The sweet spot for most engineering managers is 5-8 direct reports. Below 5, the manager lacks enough context to justify the role. Above 8, 1:1s and career development conversations get squeezed and people start feeling invisible”
800+Articles
27Interactive Tools
18Categories
6Learning Stages
Learning Path
Discover Today
LangChain
The go-to framework for wiring up LLM apps with chains, agents, and retrieval
Artifact Management & Container Registry
Central repository for build artifacts (container images, packages, binaries) with versioning and access control
Count-Min Sketch & Frequency Estimation
Estimates how often an element appears in a data stream using a fixed amount of memory regardless of stream length. The structure never needs to know the universe of possible elements in advance