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David Yin

I build with AI and share hands-on tool tests, engineering practice, and what I learn along the way.

19 years in engineering & architecture · 13 years leading tech teams · Hangzhou, China

X YouTube (English) Bilibili YouTube (Chinese)
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01 Personal Works

Products I build

A few independent projects, from idea to launch and still evolving.

All 8 products
01 New web app Learning Kaikouba See the Chinese, say it in English 02 Chrome extension Productivity Save Any Page Save any web page as a long image, PDF or Word file in one click
02 Video

Recent videos

Hands-on tests of AI coding tools and AI jargon, decoded — in English.

All 3 videos
03 Writing

Recent essays

Written when there is a judgment to make: AI coding, engineering management, indie dev and industry notes — in Chinese.

All 112 essays
  1. EN Claude Code Deleted 80% of Its System Prompt — Coding Evals Didn't Budge. Your Rules Might Be Making the Model Dumber English version · 8 min
  2. EN What Is Loop Engineering, Really? I Didn't Explain It Well Last Time — Let's Start Over English version · 7 min
  3. EN Everyone's Talking About Agents and Skills: Learn These Two Concepts and You Don't Need to Code First English version · 8 min
// NEWSLETTER · DAVID YIN

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04 Work with me

Project consulting

FDE · end-to-end delivery · one-off technical deep-dives.

Something you want shipped?
Leave me a message.

Describe your need in one sentence + where you are + the window you have in mind, leave your email, and I will reply directly — in English or Chinese. Messages land in my inbox only; nothing is public.

Good fit
Zero-to-one product delivery, architecture & engineering org reviews, AI adoption
Replies
Within ~2 business days, in English or Chinese
Not a fit
Ad placements, “can you introduce me to…”