Subtitle: How to model a secure, escrow-based marketplace for emerging economies using Prisma and PostgreSQL. In my previous article on Medium, I discussed the sociotechnical challenge of Information Poverty in the African gig economy. But as engineers, we know that solving social problems requires more than vision it requires a robust, type-safe, and scalable data architecture. 1. The Core Actor Model: User vs. Profile model User { id Int @id @default(autoincrement()) role UserRole @default(CLIENT) phoneNumber String @unique email String @unique passwordHash String profile Profile? // ... relations to orders, contracts, and services } model Profile { id Int @id @default(autoincrement()) userId Int @unique user User @relation(fields: [userId], references: [id]) verificationStatus VerificationStatus? @default(PENDING) nationalIdUrl String? // URL to encrypted storage mobileMoneyNumber String? } Engineering Decision: By using a 1:1 relation for the Profile, we keep the User model lean for frequent authentication checks while isolating heavier metadata and verification documents. 2. Modeling the Bidding Lifecycle (Service -> Order -> Proposal) ServiceOrder, and providers reply with Proposals. model ServiceOrder { id Int @id @default(autoincrement()) serviceId Int clientId Int budget Float? status ServiceOrderStatus @default(PENDING) contract Contract? // Only exists once a proposal is accepted } model Proposal { id Int @id @default(autoincrement()) providerId Int serviceId Int bidAmount Float status ProposalStatus @default(PENDING) contractId Int? } Relational Integrity: Notice the optional contractId in the Proposal. This allows multiple providers to bid on one job, but ensures that only the accepted proposal transitions into a formal, binding Contract. 3. The Trust Engine: Contract and Escrow Trust Gap. The Contract model acts as the central node for the entire transaction lifecycle. model Contract { id Int @id @default(autoincrement()) serviceOrderId Int @unique escrowAmount Float status ContractStatus @default(ACTIVE) payments Payment[] reviews Review[] } By enforcing a @unique constraint on the serviceOrderId, we prevent the "Double-Payment" bug. The contract is the only entity authorized to trigger a Payment release. 4. Localized FinTech Integration model Payment { id Int @id @default(autoincrement()) contractId Int amount Float paymentMethod PaymentMethod @default(MTN_MOBILE_MONEY) status PaymentStatus @default(PENDING) } model SystemSettings { currency String @default("XAF") currency_symbol String @default("FCFA") payment_gateway String @default("fapshi") } Why this matters: Hardcoding these enums and settings at the database level ensures that the business logic remains consistent and compliant with regional financial regulations. Conclusion enforce trust. By leveraging Prisma's powerful relational features, I have built a foundation where Information Poverty is replaced by a transparent, verifiable history of service. What’s Next? Escrow Algorithm and the Fapshi payment integration logic. In my next post, I will dive deep into the system UI then later "Fund-Lock-Release" cycle and real-time payment webhooks.