GreenCart | Multi-Vendor Organic Grocery Marketplace Flutter App Next.js

GreenCart Market is a 5-surface bundle: two Flutter apps (customer rider) plus one Next.js 16 project that is the public storefront, the /vendor portal, the /admin panel, and the only backend. It is a vertical marketplace for organic / local / farm-to-table grocers, built on a modern TypeScript stack (Next.js PostgreSQL Drizzle) — not the PHP/Laravel platforms that dominate this category. Two differentiators the incumbents lack: subscription produce boxes and product provenance / sourcing.HighlightsMulti-vendor cart → per-vendor order split — one cart spanning many stores becomes one order N sub-orders, each fulfilled, tracked, and settled independently.Product provenance / sourcing — every product carries a farm/origin “provenance card.”Subscription produce boxes — recurring weekly/biweekly boxes with skip / pause / resume.Live delivery tracking a full rider app — turn-by-turn Google Maps navigation, proof-of-delivery photo, COD cash collection.Stripe PayPal COD — platform-collected, with real refunds.Commission ledger vendor payouts — every sub-order records commission; balances accrue and settle per period.Vendor portal super-admin panel — onboarding, products, payouts, coupons, KPIs, reports, CSV export, churn.AI recipe & seasonal picks — OpenAI or Gemini, server-side, rate-limited, with a mock fallback.“Modern Agrarian” design system — one Tailwind v4 theme matching Flutter ThemeData, white-labelable at runtime.Tech stackWeb Backend: Next.js 16 · React 19 · TypeScript · Drizzle ORM · PostgreSQL (Neon) · JWT (jose) argon2 · Stripe · PayPal · COD · commission ledger · Cloudflare R2 · Vercel Cron · Tailwind v4 · shadcn/ui · recharts · OpenAI / Gemini (optional)Mobile: Flutter 3.x · Dart 3 · Riverpod 3.x · GoRouter · freezed · Dio (typed API client) · flutter_stripe · webview_flutter (PayPal) · google_maps_flutter · firebase_messaging (push) · cached_network_image · google_mobile_ads (optional) · flutter_secure_storage (JWT)What’s includedFull source for all three apps (2 Flutter 1 Next.js project/backend).Complete Drizzle schema SQL migrations.“Modern Agrarian” design system (Tailwind theme Flutter ThemeData).Branding pipeline — one SVG mark regenerates every web icon both launcher icons.Buyer documentation, 20-minute quick-start, and the Vercel Neon deploy guide.Vitest backend suites Flutter unit/widget tests.6 months Item Support free future updates.(No demo seed — the database ships empty.)