On-Chain Invoice Financing

Problem

Traditional invoice factoring is a cash-flow tax on SMEs. Suppliers wait 30-90 days for buyers to pay, while intermediaries take days to approve financing, charge opaque discounts, and leave weak audit trails - including double-financing risk from paper-based processes.

We set out to prove that receivables could be minted as first-class on-chain assets: tradeable at a transparent discount, settled with cryptographic attestations, and shippable to a production-viable standard under hackathon time pressure.

Solution

ChainInvoice (team SUInergy) turns supplier invoices into shared Sui objects with a verifiable lifecycle - Created → Ready → Financed → Paid - so suppliers get early liquidity and financiers earn short-duration yield backed by real receivables.

Sui's object model was a deliberate fit: each invoice is a living digital asset whose ownership, financing state, and settlement evidence evolve on-chain, rather than being reconstructed from account balances and event logs.

Actors & entities

Actor	Responsibility
Supplier	Creates the on-chain invoice and receives discounted proceeds when a financier funds it
Financier	Browses the marketplace, funds Ready invoices at a discount, receives face value on settlement
Buyer	Deposits escrow collateral, then settles the financed invoice at maturity
Oracle / Verifier	Signs issuance and payment attestations - the trust bridge for off-chain payment confirmation
Platform admin	Operates treasury / fee configuration and governance surfaces

Lifecycle

flowchart LR
    Tokenize["1 Tokenize — Supplier mints Invoice"]
    Collateralise["2 Collateralise — Buyer pays escrow, status Ready"]
    Finance["3 Finance — Financier funds at discount, status Financed"]
    Settle["4 Settle — Buyer / oracle pays, proceeds + fees"]

    Tokenize --> Collateralise --> Finance --> Settle

Tokenize - Supplier mints an Invoice via the factory; buyer info and document references stay hashed / off-chain where possible.
Collateralise - Buyer pays escrow so the invoice becomes Ready for the marketplace.
Finance - Financier funds the invoice at face_value * (1 - discount_bps); payment transfers to the supplier; status becomes Financed.
Settle - Buyer (or oracle-attested flow) pays the invoice; smart contracts distribute proceeds to the financier and collect platform fees into the treasury.

Approach

As team lead for four engineers, I owned end-to-end architecture and delivery across contracts, dApp surfaces, and the oracle trust model:

Move contracts on Sui - modular packages for invoice factory, invoice state, buyer escrow, funding, settlement, registry, and treasury; deployed to the Sui testnet.
Next.js dApp on Vercel - wallet-connected marketplace, business dashboard (issue + track invoices), investor dashboard (portfolio / financing), settlement flows, and admin treasury views; wired with Mysten dApp Kit.
Hybrid trust model - keep PII and raw bank data off-chain; store hashes and authority signatures on-chain; use an oracle backend for issuance and payment attestations.
Fee-aware financing - transparent discount rates in basis points, with platform origination / take-rate / settlement fee concepts aligned to a multi-sided marketplace model.

Stack

Layer	Choices
On-chain	Sui, Move
App	Next.js, TypeScript, Tailwind, wallet kit
Off-chain	Oracle signing API routes, document hash / IPFS-ready storage
Deploy	Sui testnet + Vercel

What shipped

In three days we delivered a working MVP, not a slide deck:

Shared invoice objects with status transitions enforced in Move
Marketplace listing and finance modal for Ready invoices
Business and investor dashboards against live chain state
Escrow + funding + settlement paths with treasury fee collection
Product narrative (how-it-works, pitch) matching the on-chain model

Outcome

1st place - DeFi track and Best Business Model at the Sui Foundation * Comets of Web3 hackathon. The build validated that RWA-style invoice factoring can be expressed cleanly on Sui's object-centric model under extreme time pressure - with a live demo on testnet and an auditable contract surface.

Try it out · Code