Welcome to huachenwang.net — my personal technical workspace and knowledge archive. This site is where I document system design notes, DevOps practice
Core Goal Implement a simplified Twitter with: postTweet(userId, tweetId) follow(followerId, followeeId) unfollow(followerId, followeeId) getNewsFeed(
0. Migration Overview This migration was not a simple frontend switch. It was a full production architecture upgrade, including: Data Layer EC2 local
1. Background In this study note, I documented a complete hands-on learning journey of Amazon ECS with Fargate, focusing on: How ECS actually runs wor
As I gradually moved from “following deployment steps” to actually understanding why modern delivery pipelines are designed the way they are, CI/CD st
Over the past ten days, I’ve been building something that started as a small experiment but ended up becoming one of my favorite side projects: Wisdom
This note summarizes the system design and technical insights from building a banking customer service assistant powered by retrieval-augmented genera
📌 1️⃣ Introduction Proximity Service is a key component in many modern applications: Yelp: Find nearby restaurants and shops Google Places: Return ne
📘 Problem Overview You are given a directed, weighted graph with n nodes (1-indexed), and a list of travel times times, where each element is [u, v,
