CrackingWalnuts
Today's Lineup
Pattern Pick
Dijkstra's Algorithm
DSA TemplateIntermediate
ExploreDesign Blueprint
Online Coding Judge
Low Level DesignAdvanced
ExploreScale Study
Design an Ad Click Aggregator
System DesignMedium
Deep divePacket Probe
HTTP/1.1 — The Foundation
Networking & ProtocolsBeginner
ExploreStaff+ Prep
Incident Leadership Scenarios
Staff+ InterviewAdvanced
ExploreKernel Dive
Workqueues & Tasklets
Linux InternalsAdvanced
Deep dive
Explore
DSA Templates
35Algorithm patterns & code templates
System Design
40End-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
Distributed Systems
38Consensus, replication & more
Linux Internals
84Kernel, networking & system calls
Cheat Sheets
24Quick reference cards for interviews
Recent Posts
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
System Design: LeetCode (Code Sandbox, Container Isolation, Real-Time Contests)
System Design
Apr 12, 2026 · 68 min
Leadership
DirectorEngineering Culture at Scale
“Culture is a set of decisions people make when no one is looking. It shows up in code review tone, incident response urgency, and whether someone speaks up when a deadline is unrealistic”
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”
530+Articles
27Interactive Tools
16Categories
6Learning Stages
Learning Path
Discover Today
TipTap
The headless rich-text editor built on ProseMirror with first-class Yjs support
Metrics & Monitoring
Of the three observability pillars (metrics, logs, traces), metrics are where alerting starts
Quorum Systems & NRW Notation
With N replicas, W (write quorum) and R (read quorum) define the consistency tradeoff. If W + R > N, every read sees at least one replica with the latest write because the write and read sets must overlap