YC S09

5 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.

Bump, Flock, Photoroll (unreleased) => Google Photos

S09

Inactive

Marketplace

The best way to buy a new car.

S09

Acquired

Hardware

Lockitron makes electronic locks you can control locally from your…

S09

Acquired

Open Source

The open source database for the realtime web.

S09

Acquired

Fintech

Payments for platform businesses.