How a game plays out
0:00 / 1:30PayPal AI Hackathon 2026 · PayPal sandbox
Pickleball games that settle themselves.
An AI assistant that lives in your group chat. Friends say they’re in, hold their spot with PayPal or Venmo, and after the game each one is charged their real share. Nobody chases payment requests.
The 2-minute walkthrough runs on your own phone: you organize, the page plays your friends, and you pay with a PayPal sandbox account.
The problem
Asking friends to pay you back is awkward. Asking strangers is worse.
- Someone has to ask. One person books the court, then has to ask friends for $8 in the group chat. Nobody wants to be that person.
- Not everyone is a friend. Friends bring friends. Sending a payment request to someone you’ve never met feels even worse.
- The host covers the rest. When someone drops out the night before, the organizer quietly pays their share.
With , everyone’s share is held with PayPal the moment they’re in. Nobody has to ask.
How it works
The organizer texts the group, friends hold their spot with PayPal, and it settles after the game. Nobody downloads anything: every screen opens from a text.
Say it in the group.
“in 🙌” counts as in. Claude reads every reply.
- Lives in
- Your group chat, by text. Link your own phone in the demo.
- Payments
- PayPal and Venmo, via PayPal Orders v2
- AI
- Claude (Haiku 5.5) reads every message
- Players need
- No app, no account with us. A text and a link
- Price for players
- Their share of the court. Nothing more
- Status
- Working prototype in the PayPal sandbox
For judges
Built to be trusted
Four numbers that show how the money stays safe, what it’s built with, and how it came together in seven days.
0 amounts chosen by the AI
Claude reads the chat. Plain code makes every hold, charge and refund, and a rules parser takes over if Claude is down.
8 PayPal APIs in a real game
Create order, authorize, void, reauthorize, partial capture, refund, Payouts to the organizer and verified webhooks. Venmo uses the same SDK.
1 charge per payment, even on retry
Every PayPal write sends a PayPal-Request-Id. A settle cut off by a restart is finished by the next scheduled run.
100 tests on every pull request
Money maths, the fallback parser, retries and rate limits, with typecheck, lint and build alongside them in CI.
Built with
- App
- Next.jsTypeScriptPostgresRender web serviceRender Workflows and cron
- Payments
- PayPal Orders v2Authorize, capture, void, refundPayoutsVerified webhooksJS SDK with Venmo
- AI
- Claude Haiku 5.5 reads the chatClaude Code helped write and review the code
- Messaging
- Real texts through Sendblue
- Fri Nov 6Research and concept
Rules, judges and Render Workflows. Two concepts written up; the pickleball one wins.
- Sat Nov 7Rules for the money
Late cancels, no-shows and called-off games. That night the repo is created and v1 goes live on Render.
- Sun Nov 8First real hold
First PayPal sandbox hold approved. The group-chat flow is settled, and 5 design directions explored.
- Mon Nov 9The assistant works
Claude turns a setup text into a game. Simulator, phone demo, first landing page and JUDGES.md.
- Tue Nov 10Money end to end
Payouts, refunds and verified webhooks. Lint, unit tests and CI on every pull request.
- Wed Nov 11Hardened
Edge-case review: no overcharge, survives restarts. Accessibility pass, real SMS, Paddles In brand.
- Thu Nov 12Ready for judges
Late cancels can be charged, covered or wait for a replacement. 2-minute walkthrough and sandbox proof.
Real: Claude reading every message, your own PayPal sandbox hold and capture, and the organizer’s payout. Simulated: the other players and their holds, marked SIM-.
For judgesEvery PayPal callEvery edge case, and how it’s handledSandbox proofSource on GitHub (MIT)
Run a game from your phone
Scan a code, set up Thursday’s game, and watch it fill, cancel and settle in about two minutes.