# YC S09

3 dead or acquired startups from batch S09 with completed research reports.

## Every startup playbook in our database, ready to build

Each deep-dive includes a post-mortem, step-by-step rebuild plan, and a technical spec you can paste straight into Claude Code, Cursor, or Lovable.

### Acquired

**Bump**  
Bump, Flock, Photoroll (unreleased) => [Google Photos](/content/company/bump/index.html)

### CarWoo  
Marketplace  
The best way to buy a new car.

### RethinkDB  
Open Source  
The open source database for the realtime web.