For Liquidity Providers

What you're entering

Supplying USDC to Rayyan is a mudarabah: you are the capital provider (rabb al-mal), the protocol is the manager (mudarib), and returns are profit-sharing: variable, and never guaranteed. Your capital funds murabaha sales to overcollateralized borrowers; your yield is your share of their contracted markup.

If you've supplied to Aave or Compound, the experience is identical: deposit, watch your balance grow every block, withdraw when you like. What differs is what sits underneath. Every unit of yield is a slice of a fixed, pre-agreed sale price rather than a floating rate.

The yield math

LP APY ≈ curve rate × pool utilization × LP share

All three factors are on-chain and shown in the app. Launch policy values:

Utilization	Curve rate	LP APY (85% LP share)
50%	5.75%	2.44%
65%	7.03%	3.88%
68% (band mid)	7.28%	4.21%
72% (band top)	7.62%	4.66%
80% (cap)	8.30%	5.64%

What works in your favor:

1. The utilization band (65–72%). Protocol-owned liquidity is actively managed to hold the pool in the high-yield part of its own curve. Because borrower rates are locked at borrow, this repricing affects only new borrows, never existing contracts.
2. A flat split. LPs receive 85% of streamed markup, the same mudarabah profit-sharing ratio from day one, no teaser rates, no step-downs to watch for. The split is an on-chain parameter (lpShareBps, governance-bounded 70–99%) and any change applies only forward, never to already-accrued yield.

Your yield is markup only. Settlement fees and liquidation proceeds are not depositor income: a creditor may not profit from a borrower's non-payment. The settlement fee is the operator's wage for selling a matured position's collateral as the borrower's agent, and a liquidation's surplus goes back to the borrower (see Shariah Compliance).

A note on benchmarks

If your alternative is a treasury bill: T-bill yield is interest, which is exactly what faith-motivated capital cannot hold. The permissible alternative set is 0% idle stablecoins, 1–3% Islamic savings accounts, or locked sukuk funds at 3–5% with minimums and KYC. A liquid, on-chain, certifiable 3.9–4.7% leads that set. Secular LPs benchmarking against Compound's ~2.6% supply rate can compare the table above.

Liquidity and exit

• 20% of the pool is always liquid, because borrows are capped at 80% utilization, the on-chain version of an Islamic bank's statutory liquidity reserve.
• All capital turns over within 360 days, since every position has a settlement date.
• If withdrawals exhaust the liquid buffer, further withdrawals wait for repayments, the same behavior as every pooled lending protocol (and every bank).

Risks

• Yield depends on borrowing demand: with no borrows there is no markup and no yield. The POL band and (Phase 2) RWA yield on idle capital mitigate but don't repeal this.
• Bad debt tail risk. If collateral gaps through the liquidation margin faster than liquidation executes, losses are socialized to the pool, identical physics to Aave/Compound. Mitigations: conservative collateral factors (ETH 85/87.5, WBTC 80/83), Chainlink oracles, a keeper that liquidates on the oracle tick, and reserves built from the treasury's 15% share of markup. Liquidations add nothing to reserves, because a liquidation's surplus belongs to the borrower. Losses beyond reserves fall on depositors' capital. The intended rule shares them pro rata; the contract does not yet write them down that way, so today a large loss would fall on whoever withdraws last.
• Smart-contract risk. About 460 novel lines (240 in the Comet fork, 220 in the settlement contract) on an audited base (Security & Risk), pre-audit and pre-launch today.
• Mudarabah means losses are yours. Capital-provider loss-bearing is what makes the structure permissible.

Mechanics reference

• Supply/withdraw: standard Comet supply(USDC, amount) / withdraw(USDC, amount).
• Your balance = your principal × the supply index, which rises every block with aggregate markup streaming. Streams stop per-position at settlement, enforced by the on-chain expiration queue, so no phantom yield.
• LP share (lpShareBps), utilization, and the curve rate are all public on-chain reads.