Complimentary car wash for members
Retail Notes

A Three-Yuan Car Wash—and Why the Math Actually Works

An annual membership costs 188 yuan, with 30 yuan returned. Use the weekly car wash regularly and it works out to roughly 3 yuan per visit. What looks like a loss on paper can make perfect sense in retail.

2026-10-06 · 4 min · 789 words ·  Shen Nan
Rebuilding ZISAI during the 2026 National Day holiday
ZISAI

ZISAI at 28: Technology Changes, Habits Stay

During the National Day holiday, I rebuilt ZISAI once again. Work carries responsibility; this website runs on personal curiosity. Technology, design and small details became part of something I wanted to make well.

2026-10-04 · 4 min · 803 words ·  Shen Nan