Lending

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Score-based loans

limit = tier.credit_limit + collateral_value × ltv_bps / 10_000

• Pluggable source: any contract exposing credit_score(borrower) -> Option<CreditScore { score, updated_at }>. Ankara ships manual-credit-scorer (a trusted Manager posts scores, like manual-oracle does for prices). You can swap in a scoring partner’s contract, a cooperative’s membership record, or an adapter over attestation-registry CREDIT claims. The vault never assumes a scoring model.
• Tiers (set_score_config, Manager): strictly ascending min_score, each with an unsecured credit_limit, a flat fee_bps charged on repayment, and a max_term_secs. Scores older than max_score_age are rejected.
• Collateral is optional: pass none for a fully unsecured loan, or add some to raise the limit.
• Due date instead of price liquidation: a scored loan must be repaid (principal plus fee) within its term. After that, anyone can mark_defaulted: pledged collateral goes to the Manager and a defaulted event is emitted for score sources to pick up. Scored loans are never price-liquidated.
• The ordinary open_loan / liquidate path is unchanged.

import { CollateralVault, ManualCreditScorer } from "@ankarachain/sdk";

const vault = new CollateralVault(adminAdapter, VAULT);
await vault.setScoreConfig({
  source: SCORER,
  tiers: [
    { minScore: 500, creditLimit: 200_0000000n,   feeBps: 500, maxTermSecs: 30n * 86400n },
    { minScore: 700, creditLimit: 1_000_0000000n, feeBps: 200, maxTermSecs: 90n * 86400n },
  ],
  maxScoreAge: 30n * 86400n,
});
await new ManualCreditScorer(riskTeamAdapter, SCORER).setScore("GFARMER...", 720);

// the borrower:
const farmerVault = new CollateralVault(farmerAdapter, VAULT);
console.log(await farmerVault.scoredBorrowLimit("GFARMER..."));
const { loanId } = await farmerVault.openScoredLoan({ borrowAmount: 800_0000000n, termSecs: 60n * 86400n });
console.log(await farmerVault.amountDue(loanId)); // principal + 2%

​

Group savings & lending: savings-circle

​

Rotating

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Pooled

• Members contribute once per period for rounds periods.
• Any member can borrow up to borrow_multiple_bps of their own savings (20_000 = 2× savings), so the group backs part of the loan. They repay principal plus a flat loan_fee_bps, and the fee goes into the pool.
• After the last period, each member withdraws their share of the pool, pro-rata to savings, so fees are shared. A member still owing when the pool closes forfeits their savings to the pool: the defaulter absorbs losses first, and only the remainder is shared across the group.

import { SavingsCircle } from "@ankarachain/sdk";

const circles = new SavingsCircle(organizerAdapter, CIRCLES);
const { circleId } = await circles.createCircle({
  token: USDC_SAC, mode: "pooled", contribution: 20_0000000n, periodSecs: 7n * 86400n,
  maxMembers: 15, rounds: 26, borrowMultipleBps: 30_000, loanFeeBps: 1_000,
});

SCORER=$(stellar contract deploy --wasm target/wasm32v1-none/release/manual_credit_scorer.wasm --source deployer --network testnet)
stellar contract invoke --id $SCORER --source deployer --network testnet -- initialize --admin <ADMIN>
CIRCLES=$(stellar contract deploy --wasm target/wasm32v1-none/release/savings_circle.wasm --source deployer --network testnet)