Cash Out is a decentralized invoice financing and liquidity unlocking platform built for freelancers and SMEs. It addresses the global issue of delayed B2B invoice payments—over $3 trillion locked and 50,000+ business failures annually. The platform enables instant payments upon invoice confirmation using zero-knowledge proofs (ZKPs) powered by vLayer, with all transactions executed securely and privately on the Rootstock testnet.
🔍 Real-World Problem
- 📉 61% of B2B invoices are paid late.
- 🧾 SMEs lack legal and financial resources to enforce timely payments.
- 🔒 On-chain financial transparency is avoided due to privacy concerns.
- ❌ Cash flow gaps cause 50,000+ business failures each year in the US.
🚀 The Cash Out Solution
Cash Out provides a private, verifiable, and trustless mechanism for invoice financing.
- ✅ Instant liquidity for suppliers via zk-proofs of invoice confirmation and buyer solvency.
- 🔐 Privacy-preserving financial verification (e.g., Binance/Bybit proof, cross-chain averages).
- ⛓️ Entire lifecycle is on-chain: transparent, tamper-proof, and automated.
- 📊 Uses Pyth for reliable price feeds and Rootstock Attestation Service (RAS) for claim validation.
🔨 Technologies Used
| Component | Technology |
|------------------------|------------------------------------------------|
| Blockchain Base | Rootstock Testnet |
| Privacy Layer | vLayer (ZK generation & verification) |
| Proof Attestation | Rootstock Attestation Service (RAS) |
| Oracle | Pyth Network (price conversion) |
| Cross-Chain Proofs | Time Travel & Teleport (ZK multi-chain proofs) |
| Asset History Proofs | Binance & Bybit portfolios (zk-verified) |
| Token Payout | $RIF and $USDC |
🧠 Product Workflow

👥 User Profiles
- Clients and Suppliers register on-chain via a
CreateProfile
transaction.
🧾 Invoice Lifecycle
- Business issues an invoice and sends a confirmation email.
- Supplier parses the email and generates a zk-proof of the contents.
💰 Financial Solvency Verification
- ZK-proofs of liquidity from:
- Binance/Bybit exchange history
- Cross-chain wallet balance (via Teleport + Time Travel ZK modules)
✅ Claim Verification
- Supplier submits zk-proof to claim payment.
- Creates an attestation on the Rootstock Attestation Service (RAS).
🪙 Payout
- Funds released instantly in $RIF or $USDC to supplier’s wallet.
🤹 Hacky/Innovative Aspects
- ✉️ ZK Email Proofing: Parses Gmail content and turns it into verifiable cryptographic claims.
- 🌐 Cross-chain ZK Liquidity Proofs: Aggregates multi-chain balances without revealing wallet info.
- 🧠 Proof-of-liquidity without trust: No credit scores, no raw data exposure—just pure cryptographic solvency.