Zebrasplit — split trip expenses, settle up in Venmo

Identifiers that keep the old names on purpose. The product is Zebrasplit (zebrasplit.com, scheme zebrasplit://, since 2026-10-13; Bunktab before that, Checkm8 before that). The iOS/Android bundle id com.bunktab.app, the Expo slug bunktab, the EAS project @brad.russell1/bunktab, the npm workspaces @bunktab/*, the App Store Connect record and the push key are internal and stay as they are, like the checkm8.internal setting, Vault secret and x-checkm8-secret header. Old schemes and domains keep working: bunktab:// and checkm8:// are still accepted, and bunktab.com / check-m8.io redirect to zebrasplit.com.

A group logs shared trip expenses, everyone taps Done, and close-out opens Venmo with each payment pre-filled, using the fewest payments possible. The spec is docs/zebrasplit-spec.md. The original Checkm8 spec is kept as history in docs/archive/.

Layout

Path	What
apps/mobile	Expo (React Native) app, iOS + Android, expo-router
packages/core	Pure logic: money, split types, lodging nights, settlement, Venmo links, categories, currency. Tested with vitest. No I/O.
packages/theme	Design tokens: the Pretty Good kit's roles re-coloured with Basalt & Spore
supabase/	Postgres schema, row-level security, RPCs, storage policies (migrations/), Edge Functions (functions/)
apps/web	Next.js web guest view + landing page (phase 5, not yet created)

Run

npm install
npm test                      # packages/core
npm run typecheck             # every workspace
cp apps/mobile/.env.example apps/mobile/.env   # add the anon key
npm run mobile                # Expo dev server; scan the QR with Expo Go

Database

npx supabase login
npx supabase link --project-ref qywowvkkkxldgxoatdsh
npx supabase db push          # applies supabase/migrations

Keys never enter the repo. The anon key goes in apps/mobile/.env; the service role key only in Supabase and Vercel environment variables.

Rules

• Money is integer cents everywhere.
• Spore Chartreuse means "tap this" and nothing else.
• Every table has row-level security; a user sees a trip's data only as a member of that trip. Split and payer sums are re-checked in the database.
• The Venmo link format is undocumented; it lives in one function (packages/core/src/venmo.ts).