Launch two-sided marketplaces on one contract

Verify sellers by tier, split each payment through your payment processor, push live order status to buyers, and thread every buyer-seller conversation, all through one SDK.

Get early access Explore the platform

Payouts and disputes depend on the same order record

A marketplace usually needs to verify buyers and sellers, pay sellers through a processor, show each order's status as it changes, and store listings and dispute evidence. When a separate vendor does each of those jobs, a payout can stall whenever your code fails to copy an order's status from one vendor to the next. Conjoin does all of those jobs under one contract, so the payout, the order status, and the dispute record all refer to the same order in the same system.

An order, from listing to payout

Below, a single order goes through seller verification, listing, payment, payout, and the occasional dispute on Conjoin.

Onboard buyers and sellers at different verification tiers

Buyers register through Conjoin Auth with a social login or an email link and add a delivery address. Sellers, by contrast, reach higher verification tiers through the identity verification provider that you connect, which checks their business registration and bank details. Set, for each tier, which categories a seller can list in and how much they can earn before your team reviews them. Auth puts the user's role and verification tier in every access token, so your listing, payout, and dispute APIs apply the same rules.

Outcome

A buyer can check out after one sign-in, while a seller lists products only after reaching the tier that you require.

Record every order change for dispute review

Conjoin Database stores listings, orders, reviews, and dispute records, with a history of every state change. Sellers upload product photos, documents, and dispute evidence to Conjoin Storage. Storage resizes each photo through URL parameters, so a phone and a desktop browser each download the size that they display. Reviewers open evidence files through signed URLs that expire after the time that you set. Once an order closes, Storage moves its files to archive storage under the lifecycle policy that you configure and deletes them after the dispute window ends.

Outcome

A dispute reviewer can step through the history of an order and open every file that the buyer and the seller upload.

Pay sellers on schedule and push order updates

When a buyer pays, Conjoin Billing instructs your processor to delay the seller's share until the seller fulfills the order, then releases it on the payout schedule that you set, minus your platform fee. From then on, Conjoin Relay pushes each change in the order's status to the buyer's notifications, the seller's dashboard, and your fulfillment partners as it happens. At the same time, Conjoin AI scores the buyer and seller behavior that you choose to track, such as repeated return abuse or an unusual buying pattern, while your processor screens each card payment for fraud.

Outcome

Your finance team can reconcile the day's payouts and platform fees from Billing's records alone.

Rank listings with your own code

Deploy your ranking logic, promoted listings, dispute rules, and regional fees as code on Conjoin Runtime. For the conversation around each order, Conjoin Messaging threads each message between a buyer and a seller against that order, where your support team can read the full history. Messaging also sends order confirmations and delivery updates on the recipient's preferred channel.

Outcome

When a new support agent picks up a dispute, the whole conversation is already on the order.

What one contract covers, and what checkout design can add

Baymard Institute estimates the conversion gain from its large-scale checkout usability testing, while the other two figures are about what a Conjoin contract includes.

Same stack

for buyers, sellers, and search

One contract

for verification, payouts, and disputes

35%

potential conversion gain for a large ecommerce site from better checkout design

Sources: Baymard Institute, 'Cart Abandonment Rate Statistics' (updated 2025).

Controls for buyers, sellers, and payouts

Auth, Billing, Relay, and Storage are parts of one Conjoin project, so your code can use a seller's tier from Auth to set their payout limit in Billing.

Tiered seller verification

Sellers raise their payout limit by completing a higher verification tier, which your verification vendor confirms to Auth.

Delayed payout and split payouts

Billing splits every payment between your platform fee and the seller, whose portion the processor pays out after fulfillment.

Buyer-seller messaging with transaction context

Messaging removes spam and shared contact details from each message between a buyer and a seller before it delivers that message to the other party.

Real-time order state

When a carrier scans a package, your backend publishes the scan to a Relay broadcast channel, from which the buyer's open order page receives the update in under 50ms.

Seller-behavior risk scoring

When a seller's return rate or order volume changes sharply, a Conjoin AI workflow can pause the seller's next payout at an approval step until your trust team reviews it.

Ranking code on Runtime

Your ranking code on Runtime can query listings in Database through the preinstalled SDK and boost promoted listings by the rules that you write.

Bookings and physical goods on the same services

The two builds differ mainly in when Billing pays the seller: after a session for a services marketplace, and after delivery for a product marketplace.

Services marketplace with scheduled bookings and split payouts

Clients sign up through Conjoin Auth with a social login, while providers also pass a business-registration check before their first booking. When a client books a session, Conjoin Database records it against the provider's availability, after which Conjoin Relay pushes the booking to the client and the provider in real time. Providers upload portfolios and booking documents to Conjoin Storage, which shares each file through a link that expires. Conjoin Billing charges the client at booking but has the processor hold the provider's share until the session is complete. Before Billing releases that share, Conjoin AI scores the provider's trust signals and can send the payout to manual review. For each booking, code on Conjoin Runtime applies the regional tax rules and your dispute rules. Conjoin Messaging attaches the conversation between the client and the provider to the booking and sends each of them reminders on the channel that they pick.

What this delivers

If a client disputes a session months later, your team can still open the booking, the payment, the messages, and the provider's files.

Product marketplace with image optimization and review history

Sellers complete higher verification tiers through Conjoin Auth before they can list products, although buyers need only a social login. Conjoin Database stores the catalog, reviews, orders, and dispute records with their full history. Each product image is in Conjoin Storage, which resizes it for the screen that displays it. At checkout, Conjoin Billing charges the buyer's card and pays the seller once the carrier delivers the order. Every time a carrier scans the package, Conjoin Relay pushes the new status to the seller and the fulfillment partner. Code on Conjoin Runtime ranks listings by seller performance, while Conjoin AI flags sellers with rising returns or falling ratings for review. Buyers and sellers talk through Conjoin Messaging, which files each conversation under its order.

What this delivers

Sellers with better delivery and review records rise in search, because your ranking code queries the same order records in Database that Billing uses for payouts.

Build your next app on Conjoin

Conjoin will open with a free Build tier, while the pricing page already lists the launch prices for Pro and Business. If you tell us what you're building, we'll talk you through early access.

See pricing Get early access