4Fleet
Multi-tenant B2B fleet-management SaaS with an AI agent for email-to-quote parsing, dynamic pricing engine, and Stripe billing - live at 4fleet.io.
// delivery facts
Multi-tenant SaaS
Architecture
Full RLS isolation per company, company_id scoped throughout
Claude API
AI pipeline
Email-to-quote agent: read, extract, price, respond
Live - 4fleet.io
Status
Running in production; deployments automated via Vercel
5
Integrations
Stripe, Gmail API, Google Maps, Supabase Realtime, Claude API
The challenge
Fleet and transport operators lacked a single system capable of receiving quote requests by email, pricing them automatically, and managing bookings end-to-end without manual relay.
- 1
Quote requests arrived by email and required manual extraction of trip details before pricing could begin
- 2
No consistent pricing engine - each operator applied rules ad hoc, introducing errors and delays
- 3
Driver assignment, invoicing, and route mapping lived in disconnected tools with no shared state
- 4
Multi-company isolation was essential but unachievable with off-the-shelf software
How it was built
Purpose-built multi-tenant SaaS on Next.js and Supabase with a Claude API agent pipeline for email ingestion and a database-driven pricing engine.
Row-level security (RLS) on every Supabase table scoped to company_id - full data isolation per tenant from day one
Claude API agent reads incoming Gmail messages, extracts trip details (origin, destination, passengers, schedule), and prices them against a rule-based engine - no human needed in the loop for standard quotes
Dynamic pricing engine stores pricing rules in Postgres; operators configure distance tiers, time multipliers, and vehicle-type overrides without touching code
Stripe billing integrated for subscription management; Google Maps API used for route distance calculation feeding directly into pricing
Full booking lifecycle: driver assignment, trip tracking, invoice generation - all inside one system with a shared Supabase Realtime layer
What shipped
Production SaaS deployed live at 4fleet.io - multi-tenant architecture, AI-driven quote pipeline, and full booking lifecycle shipped.
// full stack
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