Fixed-rate lending on an order book.

GreenJay is a fixed-rate, fixed-term lending market for crypto assets: the money-market model bank trading desks use, on an order book instead of a pool, open to anyone with a wallet. Lenders and borrowers state their own rate and term, and orders match by price–time priority. The smart contract holds the cash and the collateral, enforces margin and settles at maturity. Phase 1 lends USDG against ETH collateral.

Aave and Compound are pools with a floating rate, while GreenJay is an order book where the rate and the term are fixed when an order matches. In a pool, lenders deposit into a shared pot, the rate moves with utilization along a curve chosen by governance, and there is no maturity. On GreenJay you choose your rate and your term, and the amount due does not change until maturity. Aave is not a competitor here; it is the anchor GreenJay’s rates should make sense against.

You place a lend order that states the amount, the term and your rate, for example “I lend 10,000 USDG for 30 days at 5.25%.” The full amount locks when you place the order, and lenders post no collateral. When the order matches, the rate and the amount due are fixed, and at maturity you claim your share.

You deposit ETH as collateral and place a borrow order with a term and the highest rate you will pay, for example “I borrow 10,000 USDG for 30 days at up to 5.50%, against ETH.” Collateral is measured against the amount due at maturity, and 140% is required to open a position. Once the order matches, the rate and the amount due are fixed, and you repay that amount at maturity.

Not yet: GreenJay starts as a cash market, lending USDG against ETH collateral. A later phase plans a mirror market to lend and borrow tokenized equities, such as Robinhood stock tokens, at a fixed rate for a fixed term against stablecoin collateral, and to accept them as collateral on the cash side. Any asset is listed only with a manipulation-resistant oracle, deep liquidity, a haircut matched to its volatility and no restriction that could block liquidation. Robinhood stock tokens are not offered in the US, and these markets would not be available to US persons.

Lenders and borrowers set the rate themselves, in their orders; no utilization curve sets it. Rates are quoted in basis points on a 5 bp grid, and orders match by price–time priority. The rate is fixed at matching, and interest is simple ACT/365: amount due = principal × (1 + rate × days / 365).

Exit is at maturity: the borrower repays the amount due, and each lender then claims their share. The contract does not push payments; each lender calls claim, so one failing transfer cannot block everyone else. Maturities roll, so a 30-day loan matures 30 days after it matched.

A position whose collateral falls below 120% of the amount due can be liquidated. The margin corridor has three thresholds: 140% to open a position, a 130% fill floor below which a resting borrow order is removed instead of filled, and 120% for liquidation. Borrowers can top up collateral to stay above them. Liquidation is implemented in a later milestone and, until the keeper bot ships, is triggered manually.

A fixed rate can sit above Aave’s supply rate because pool lenders earn the borrow rate only on the borrowed share of the pot, minus a reserve. That keeps a pool’s supply rate below what its borrowers pay. On GreenJay, lenders and borrowers meet at one rate and only a protocol fee applies, so a lender can earn more than a pool’s supply rate while the borrower pays less than its borrow rate.

GreenJay launches on Robinhood Chain and Ethereum, with more EVM networks to follow. Robinhood Chain is an Arbitrum-based, EVM-compatible Ethereum L2 with no public mempool, which lowers front-running risk compared with L1. Price feeds come from Chainlink.

The on-chain yield curve is the term structure of rates that GreenJay’s matches produce, one point per term: 7, 30 and 90 days to start. It is made by the market, not by a formula. The plan is a time-weighted average of matched rates per term that other contracts can read; this read layer is planned for a later milestone.

Not yet: GreenJay is in active development and has not been deployed. The testnet is coming soon and will be announced on X first.

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No to both: GreenJay has not been audited, and there is no token. Do not use it with real funds. The contracts are built tests-first, with invariant fuzzing and mutation testing, but that is not an audit. No token exists or is planned before the product works and legal review is complete.