07 Full-stack platform · web + mobile + infrastructure
B2B wholesale platform for a U.S. Latin food distributor
The entire wholesale chain — catalog, invoicing, warehouse, routing, delivery — as one system, operable by a non-technical owner.
AThe problem
A wholesale food distributor in Austin ran its whole operation across disconnected tools: tiered pricing in one place, ordering in another, invoicing in accounting software, warehouse picking on paper, dispatch and routing by phone. Every handoff was a place for the number to change. And the person who had to run all of it every day is not technical.
BWhat we built
One monorepo — web app, mobile app and a shared package — covering the entire chain end to end: tiered-price catalog → checkout → QuickBooks invoice with a payment link → wave planning → scanner-based picking → verification with separation of duties → dispatch → optimized route → GPS delivery → financial analytics. Five operational roles, one system, built so the owner can run it without a developer on call.
CSignature pieces
The parts worth looking at.
- 01
One pricing engine, three consumers
Pricing and totals live in a shared TypeScript `core` package consumed identically by web, mobile and server. The server recalculates every total and never trusts an amount sent by a client. A guard makes a $0 sale structurally impossible rather than merely unlikely.
- 02
Charge-mismatch detection
The system re-reads every QuickBooks invoice after the fact and raises an alert when the real invoice total differs from what the customer was shown. Money discrepancies surface on their own instead of waiting to be noticed.
- 03
Adversarial multi-agent audit before production
Domain auditors swept each area, then a second set of skeptical agents tried to refute every finding against the actual code, in rounds. It caught money-handling defects that manual testing had not.
- 04
Warehouse and session controls
A WMS with separation of duties enforced on the server (not just hidden in the UI), instant session revocation via token-versioned JWTs, and three operational switches: test mode, coming-soon and emergency shutdown.
DDelivered
- Web application in production: ~437 products, admin panel, sales-rep module, warehouse management, routing and deliveries
- iOS and Android production builds compiled via EAS, with business parity to the web across all five roles
- CI/CD with automatic rollback on failure
- 137 automated tests gating deployment
- Encrypted backups and monitoring
- A tax-decision document citing 26 official sources, plus runbooks written for a non-technical operator
EOutcome
Functional coverage of the complete business chain in a single system across five operational roles — with money safety as the measurable outcome: charge-match verification, structural impossibility of a $0 sale, and duplicate-invoice protection, all held up by 137 automated tests that block a deploy on regression. Built for autonomous operation by a non-technical owner, with runbooks and documentation to match.
FStack
- Next.js 15
- React
- TypeScript
- Tailwind
- Prisma
- SQLite (WAL)
- Expo / React Native
- Zod
- QuickBooks Online API
- JWT (jose)
- node:test
- GitHub Actions
- gitleaks
- Hetzner VPS
- PM2
- Nginx
- Let's Encrypt
- EAS Build
- GPS API
- SSE
- i18n EN/ES
GStill to supply
- [TODO-DUEÑO] Engagement duration.
- [TODO-DUEÑO] Business metrics you are cleared to publish.
- [TODO-DUEÑO] Anonymized screenshots or a system diagram.
- [TODO-DUEÑO] Decide: name the client, or keep the neutral descriptor.