Forepay
The first zkTLS revenue-backed lending pipeline on Stellar.
Forepay lets a content creator prove their ad revenue privately and turn that proof into a stablecoin advance on Stellar, without sharing account credentials and without posting collateral.
Reviewing this for Instawards? Start at docs/evidence.md — it answers the
SOW §6.2 checklist row by row, with a clickable link for every claim and a plain statement of what
each row does not show.
Status: the advance contract is live and source-verified on Stellar testnet
(CCQFL2Q6…I2HS),
funded with 105 testnet USDC, and has disbursed and been repaid against verified proofs. The
backend and proof relay are running, and the creator front end is merged. What is not done yet is
listed in the evidence pack rather than left for a reader to work out.
The scope is a 30-day technical demonstration on Stellar testnet, funded through Stellar
Instawards (Ambassador Chapter Indonesia). It is not a lending product and uses no real funds.
The problem
Content creators earn real, recurring platform revenue (for example Google AdSense payouts), but they cannot borrow against that income on-chain without either:
- handing over their account credentials so a lender can check their earnings, or
- posting collateral they usually do not have.
Existing lending on Stellar points elsewhere: cash-flow and receivables lenders underwrite business invoices, not individual creators, and the largest money market is over-collateralized.
The idea
Reclaim's zkTLS verifier is already live on Stellar. Forepay wires a privately proven revenue figure into a lending flow:
- Prove: the creator proves their trailing AdSense revenue with Reclaim zkTLS. Credentials are redacted; an attestor signs the extracted figure.
- Verify: a Soroban contract checks the proof on-chain through Reclaim's deployed
verify_proof integration.
- Size: the contract computes an advance with a deterministic rule, a capped multiple of the proven revenue.
- Disburse: the contract sends USDC (as a Stellar Asset Contract token) to the creator's address.
- Track: a repayment ledger records what was advanced and what has been repaid.
Safety checks
| Check | Prevents |
|---|
| Proof verification (attestor signature) | Forged or tampered proofs |
| Nullifier registry | Reusing one proof for multiple advances (replay) |
| Proof-to-address binding | Someone else using a creator's proof |
| Freshness check | Stale proofs with outdated revenue |
Repository layout
forepay/
├── sc/ # Soroban smart contracts (Rust): advance contract
├── be/ # Reclaim AdSense provider and proof relay
├── fe/ # Creator app (Next.js): connect wallet, prove revenue, accept advance, view repayment
└── landing-page/ # Project landing page (Next.js)
30-day scope
| Week | Focus | Expected output |
|---|
| 1 | Reclaim verify_proof on testnet, first AdSense provider, repo and CI | One real AdSense revenue proof verified on testnet; reviewed design |
| 2 | Advance contract: verification, nullifier, sizing, USDC disbursement, repayment ledger | A valid proof sizes and disburses a USDC advance on testnet; passing tests |
| 3 | Proof relay, proof-to-address binding, creator front end | A creator completes the full flow through the front end on testnet |
| 4 | End-to-end demo and negative cases, hardening, docs | Full pipeline plus invalid, replayed and stale proofs rejected on testnet; demo video |
Deliverables
Out of scope for this phase
Real credit underwriting and default recovery, licensing and KYC, mainnet funds, Blend integration, revenue sources beyond AdSense (YouTube, Twitch, Spotify), and third-party audits. These are planned for later phases.
Tech stack
- Stellar testnet, Soroban smart contracts (Rust)
- Reclaim Protocol zkTLS: Soroban verifier and zkFetch
- USDC via Stellar Asset Contract
- Next.js, TypeScript, Tailwind CSS, Stellar Wallets Kit
Getting started
Two workspaces: pnpm at the root for the TypeScript packages, Cargo in sc/ for the
contracts. Pinned versions and the reasoning are in CLAUDE.md.
Prerequisites: Node ≥ 22, pnpm 12 (corepack enable or npm i -g [email protected]), rustup
(the toolchain in sc/rust-toolchain.toml installs itself), stellar-cli 28.1.0.
# TypeScript: install once at the root, then run any package
pnpm install
pnpm --filter fe dev # creator app
pnpm check # lint + typecheck + test, every package
# Contracts
cd sc
cargo test --workspace --all-features
stellar contract build --package forepay-advance
Links
License
AGPL-3.0-only. The proof relay depends on @reclaimprotocol/zk-fetch, which is AGPL-3.0,
so Forepay is too — see docs/licensing.md.
