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I built a multi-tenant fintech operations platform. React on the frontend, Node API, Postgres with row-level tenant isolation underneath. It connects to Stripe, Plaid, QuickBooks and Xero through verified webhooks. Every event signature is checked against the raw request body, duplicates collapse into a durable idempotent inbox, and each event gets matched to the right tenant on the server before anything touches the ledger.
Money is stored in minor units, never as floats. The reconciliation engine catches amount mismatches, orphan payments and stale cursors. Anything it can't explain lands in an anomaly queue with a dead-letter lane. There's also an AI document pipeline, OCR plus extraction with prompt-injection canary tests, and an e-sign flow.
The test suite runs 325 tests green against a real Postgres. Dockerized, with database migrations and a disaster-recovery drill script.
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Someone asked for a tool like yours on Reddit an hour ago. Did you see it?
Riffle finds buying conversations so you can be the answer.
Waitlist open: rifflehq.com
Nice design
🏢 The Business & The "Greasy Hands" Dilemma:
We built DockFlow (Biscayne Marine OS) for Elena "Rico" Rossi, a solo mobile boat engine mechanic operating "Biscayne Mobile Marine" in Miami, Florida.
Elena drives a mobile workshop van to marinas and canal slips to repair high-performance boat engines (Yamaha, Mercury). But she faced a brutal daily dilemma:
The Greasy Hands Barrier: When working, both of her hands are covered in black engine grease inside noisy boat engine compartments. She physically cannot pick up her phone to answer customer calls.
The Traffic & No-Show Trap: Over 35% of boat owners would cancel after Elena had already driven 45 minutes across Miami bridge traffic in her work van.
Logistics Chaos: Between texting back and forth for marina security gate PINs, boat parking slip numbers, and checking if ocean tides were too shallow to run boat engines, Elena was losing 14+ hours every week just playing phone tag.
⚡ What We Built in Lovable:
We completely rebuilt the moment an inbound customer inquiry turns into a confirmed, paid booking without Elena ever touching her phone:
Marketing Landing Page (/): An executive business homepage with an interactive 3-slide hero carousel explaining the service, problems eliminated, and dockside repair guarantees.
Customer Fast-Track Booking (/book):
Real Microphone Voice Intake: Boaters stranded at a dock don't type long forms. They speak into their phone or record their engine's warning sound using HTML5 microphone capture, and the system extracts their boat specs and symptoms automatically.
Water Depth Safety Check: Verifies Biscayne Bay ocean tide levels (+1.8 ft flood tide) to ensure the water is deep enough to safely lower and test the boat engine without hitting mud.
Smart Neighborhood Routing: Groups appointments by marina cluster (Coconut Grove, Miami Beach) so Elena doesn't crisscross the city.
$175 Deposit Lock: Collects an upfront card deposit to eliminate no-shows.
Self-Service Reschedule & Cancel: Customers can reschedule or cancel in one tap without calling Elena.
Elena's Mission Control (/owner):
Sequential 1-2-3-4 Biscayne Bay route map.
Van Pre-Flight Inventory Matcher: Automatically checks Elena's van shelves (Bin 3B) for replacement cooling parts to guarantee 100% first-time fixes before she drives out.
One-tap status updates ("On the way", "Arrived", "Job Done") that send automated SMS updates to the customer.
Automatically archives completed repairs into a dedicated History & Invoices log.
Realtime Auto-Healing Waitlist Waterfall:
When a boater cancels last minute, a Supabase Realtime broadcast triggers an instant 5-minute countdown alert to the next standby boater in line (Capt. Marcus Vance), auto-filling the vacant spot with zero manual texting!
Miami Localization & Enterprise Polish:
Fully bilingual in English and Spanish (over 60% of South Florida boaters speak Spanish).
Light and Dark mode themes.
Powered by a scalable Supabase database backend.
📈 Measurable ROI:
⏱️ 14 Hours Saved Weekly in manual scheduling and phone tag.
🛡️ Zero No-Shows thanks to upfront card deposits.
🚗 2+ Hours Saved Daily in Miami bridge traffic via neighborhood clustering.
🔧 No Wasted Parts Runs with van inventory pre-flight matching.
Live App: https://dockflow-biscayne.lovable.app/
lovablechallengeFull Stack DevelopmentLow-Code/No-Code DevelopmentWeb DevelopmentLovableNext.jsSupabase
Amazing! Love the backstory and a female boat mechanic with greasy hands. Well done.
I built PREBUYR in Lovable for the @Lovable challenge — a route-aware booking system for mobile pre-purchase vehicle inspections.
The problem: a buyer wants the car inspected, the seller controls when the vehicle is available, and the inspector is already moving between appointments. A normal booking calendar can show a “free” slot that the inspector physically can’t reach.
PREBUYR turns that three-way coordination into one flow:
→ The buyer requests an inspection
→ The seller shares when the car is available
→ PREBUYR checks the inspector’s existing route, travel time and operating buffer
→ The seller sees only reachable appointment times
→ Once confirmed, the buyer and inspector update automatically
→ Rescheduling keeps the same appointment in sync instead of creating a duplicate
The key idea is simple:
Free doesn’t always mean reachable.
The current demo is built around a solo inspector serving the Denver metro area, but the same coordination layer can scale much further — from one inspector, to a multi-inspector company with multiple service areas, and eventually to a marketplace where customers can choose between specialists while the system coordinates availability and routing behind the scenes.
The goal is to remove as much manual scheduling and back-and-forth from the business owner as possible:
From “Can I book?” to “You’re booked.”
Partner certification note: in accordance with the challenge requirements, I submitted an application for the Lovable Partner certification. However, I’m not currently eligible to receive the certificate because I only started using Lovable at the beginning of this challenge, while the certification requirements include more than 3 months of subscription history and more than 3 published applications.
