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
Z-Algorithm
DSA TemplateAdvanced
ExploreDesign Blueprint
Regex Matcher
Low Level DesignAdvanced
ExploreScale Study
Design a Chat System with E2EE
System DesignMedium
Deep divePacket Probe
mTLS — Mutual Authentication
Networking & ProtocolsAdvanced
ExploreStaff+ Prep
Legacy System Modernization
Staff+ InterviewAdvanced
ExploreKernel Dive
Linux Namespaces (PID, NET, MNT, UTS, IPC, USER)
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
DirectorAI Strategy for Engineering Leaders
“Start with use case identification, not technology selection. Ask 'what problems can AI solve for us,' not 'how do we use GPT-4'”
Org Design
EnterpriseSecurity Team Integration
“Application Security (AppSec), Security Operations (SecOps), and Governance/Risk/Compliance (GRC) are three distinct functions that require different skill sets, tools, and team structures. Treating security as one monolithic team breaks down past 5-6 people”
800+Articles
27Interactive Tools
18Categories
6Learning Stages
Learning Path
Discover Today
Yjs
The CRDT library that makes real-time collaboration work without a central authority
Auto-Scaling Patterns
Dynamically adjusts compute capacity based on demand. Scales out under load, scales in when idle.
Bloom Filters & Probabilistic Membership
Answers 'is this element in the set?' with zero false negatives and a tunable false positive rate. If a Bloom filter says no, the element is definitely not there. If it says yes, the element is probably there