Context
FechaRacha supports a Brazilian coordination use case: people share a goal, invite contributors, and track declared contributions through a WhatsApp + Pix-oriented journey. The product does not custody funds.
Product problem
Shared contribution flows need to be simple enough to invite others, while still making ownership, membership, notifications, and progress states trustworthy.
Technical approach
- Built with Next.js 16, React 19, and TypeScript.
- Used Supabase Auth, PostgreSQL, and Realtime with Prisma, Zod, Resend, and Vitest.
- Implemented role-derived capabilities and contributor ownership checks at the query boundary.
- Added membership-aware visibility, shareable invitation links, notification deduplication, and goal-status transitions.
- Designed safeguards around hashed join tokens, expiry and use limits, authorization revalidation, audit events, and minimized PII.
Evidence of behavior
Behavior tests cover ownership restrictions, pending-invitation reuse, atomic exhaustion of the 50th invitation slot, notifications, and state transitions. Product pricing, expansion, and monetization remain roadmap hypotheses rather than shipped claims.