Développement d'Annuaire de Négociants en Diamants

A custom diamond trader directory built on Next.js and Supabase costs between $120K and $400K depending on scope. The lower end covers core 4C filtering, GIA cert verification, dealer profiles, and basic escrow. The upper range adds RapNet and IDEX feed import automation, advanced memo workflow with insurance tracking, multi-currency wire support, mobile apps for on-the-go dealers, and white-label multi-tenant architecture where each dealer group gets a branded sub-domain. Compare this to $400K or more on Magento or WordPress multi-vendor setups that still leave you paying for third-party plugin licenses annually. At $120K you own the full codebase and pay zero per-seat fees to RapNet or IDEX. Ongoing hosting and maintenance runs $2K to $5K per month on Vercel and Supabase Pro.

Yes. We build automated importers that pull RapNet CSV exports and IDEX API feeds on a configurable schedule -- hourly, daily, or on-demand. Each listing is normalized to your directory schema: GIA report number, 4C grades, measurements, fluorescence, symmetry, polish grade, Rap price percentage, and dealer ID. Deduplication logic matches stones by cert number so a diamond listed on both RapNet and IDEX appears once in your directory. Dealers can also manually upload stones via a dashboard CSV uploader or single-stone form. The importer handles 100K+ rows per batch without timeout, running as a background Supabase edge function.

When a dealer adds a stone, our system sends the GIA report number to GIA's Report Check service and compares the returned data -- carat weight, color grade, clarity grade, cut grade, fluorescence, and plot diagram -- against the dealer's submitted values. If any field mismatches by more than a defined tolerance, the listing is flagged for manual review before it goes live. We also support IGI, AGS, and GRS verification endpoints. This prevents fraudulent or altered cert data from reaching your buyers. Verification runs in under 2 seconds per stone and can batch-process imports at ingestion time. Verified listings display a cert-verified badge with the lab logo.

We integrate Stripe Connect for escrow, commission splits, and dealer payouts. When a buyer commits to a stone, funds are held in escrow until the buyer confirms receipt and passes a 48-hour inspection window (configurable per your terms). For high-value transactions above $25K, we support wire transfer escrow via a dedicated trust account integration. Memo transactions use a separate workflow: no funds change hands until the buyer converts the memo to a purchase or returns the stone within the agreed window. Commission rates of 1% to 3% are automatically deducted before dealer payout. Multi-currency support covers USD, EUR, INR, and HKD -- the four most common currencies in the GJEPC and AWDC trade corridors.

Dealer onboarding includes a KYC step where we collect business registration documents, GJEPC or AWDC membership numbers, Kimberley Process Certificate copies, and a government-issued ID for the account holder. Our system cross-references GJEPC's public exporter directory and AWDC's member list. Dealers who meet AGTA ethical guidelines or hold NGJA membership can display those badges on their profiles. AML screening runs the dealer's legal entity name and principal owners against OFAC, EU, and UN sanctions lists. Unverified dealers cannot list stones or receive payments. Re-verification runs every 12 months or when a dealer updates their entity information.

Yes. Your schema includes a stone-type field that separates natural and lab-grown diamonds at the database level. Buyers can filter by type, and your directory can enforce display rules -- for example, never showing lab-grown results alongside natural stones in the same search, which aligns with AGTA and JTA disclosure guidelines. Lab-grown stones reference IGI or GCAL reports, while natural stones reference GIA, AGS, or GRS reports. Pricing logic can use separate Rap list percentages or your own custom pricing index. If your niche is lab-grown only, we strip the natural diamond schema entirely and optimize the filter UI for CVD vs. HPHT growth method, post-growth treatment status, and lab of origin.

Your first 50 dealers can list stones on a live beta directory in 16 weeks from project kickoff. Weeks 1 through 5 cover audit, architecture, and data modeling. Weeks 6 through 11 deliver the core directory build with 4C filters, cert verification, and dealer dashboards. Weeks 12 through 14 add escrow, KYC, and compliance. Weeks 15 and 16 run beta onboarding with real inventory imports from RapNet feeds. After beta, we transition to a monthly retainer of $2K to $5K for hosting, monitoring, bug fixes, and feature iterations. Most directory founders see their first paid dealer subscriptions within 30 days of public launch.

You own 100% of the codebase, all dealer data, all transaction records, and every stone listing in your database. The Next.js frontend and Supabase backend deploy to your own Vercel and Supabase accounts. There are no per-seat licenses, no revenue-share clauses, and no vendor lock-in. If you decide to move hosting to AWS or self-host Supabase, the code runs without modification. This is the core difference from building on RapNet or IDEX infrastructure, where your dealers' data lives on their servers and your access disappears the day you stop paying. Your IP is your IP from day one of the engagement.