Reserve Attestation & Compliance

Two opt-in primitives for anyone issuing a reserve-backed asset (a stablecoin, or any token promising 1:1 backing) or operating under a compliance regime. Both are Stellar-only.

reserve-attestation — proof of reserve

Designated attestors (an auditor, a custodian bank, the issuer’s treasury) post the current off-chain reserve balance. Anyone can check backing before transacting.

Quorum — with quorum = n, a report is finalized once n distinct attestors have submitted for the current round. The lowest submitted amount is published, so one attestor over-reporting can’t inflate the reserve. quorum = 1 is a single-poster setup shaped like manual-oracle.
Staleness — is_stale() is true with no report, or once the latest report is older than staleness_threshold seconds. A half-filled round older than the threshold is discarded on the next submission.
Units — amounts are in the asset’s smallest unit (same decimals as the token), so they compare directly against its live total_supply.

Function	Access
`initialize(admin, asset, attestors, quorum, staleness_threshold)`	once
`submit(attestor, amount, report_hash) -> bool` (true = finalized)	attestor
`add_attestor` / `remove_attestor` / `set_quorum` / `set_staleness_threshold`	admin
`latest_report()`, `get_report(round)`, `get_reserve() -> (amount, ts)`, `pending_round()`	anyone
`is_stale()`, `outstanding_supply()`, `collateralization_bps()`, `is_fully_backed()`	anyone

is_fully_backed() = fresh report and reserve ≥ the asset’s live total_supply.

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

// As an attestor
const reserve = new ReserveAttestation(attestorAdapter, RESERVE);
await reserve.submit(1_000_000n * 10n ** 18n, "0x" + sha256Hex(bankStatementPdf));

// Anyone, before accepting the asset
const reader = new ReserveAttestation(anyAdapter, RESERVE);
if (!(await reader.isFullyBacked())) throw new Error("reserve stale or below supply");
console.log(await reader.collateralizationBps()); // 10_000 = exactly 1:1

RESERVE=$(stellar contract deploy --wasm target/wasm32v1-none/release/reserve_attestation.wasm --source deployer --network testnet)
stellar contract invoke --id $RESERVE --source deployer --network testnet -- initialize \
  --admin <ADMIN> --asset <TOKEN> --attestors '["<ATTESTOR_1>","<ATTESTOR_2>"]' --quorum 2 --staleness_threshold 86400

compliance-policy — freeze, clawback, transfer rules

Beyond the yes/no identity gate, regulated issuance usually requires the issuer to be able to freeze or reverse a specific holder’s balance (court order, fraud, sanctions). Every fungible template (farmland, commodity, real estate, invoice, carbon credit, mining rights) now has an optional compliance_policy slot. When a policy is attached, the token asks it can_transfer(token, from, to, amount) before every transfer, mint (from = None) and burn (to = None). With no policy attached, tokens behave exactly as before. The reference compliance-policy contract enforces:

Freeze — a frozen account can’t send, receive or burn. The reason (e.g. a court-order reference) is stored on-chain.
Per-transfer cap — optional maximum for holder-to-holder transfers (mints and burns aren’t capped).
Clawback — forced burn, or forced transfer to a recovery address. Works even while the holder is frozen. Only the attached policy contract can trigger a token’s clawback, so a token without a policy can never be clawed back.

Token entry point	Access
`set_compliance_policy(Option<policy>)`	token Manager
`compliance_policy()`	anyone
`clawback(from, amount, to: Option<Address>)`	the attached policy contract only

Policy function	Access
`freeze(account, reason)` / `unfreeze(account)`	policy admin
`set_max_transfer_amount(amount)` (0 = none)	policy admin
`clawback(token, from, amount, to)`	policy admin
`is_frozen`, `freeze_record`, `max_transfer_amount`, `can_transfer`	anyone

One policy can serve every token an issuer runs; freezes apply to all tokens pointed at it.

import { AssetRegistry, CompliancePolicy } from "@ankarachain/sdk";

const policy = new CompliancePolicy(adminAdapter, POLICY);
await new AssetRegistry(adminAdapter, TOKEN, "invoice").setCompliancePolicy(POLICY);

await policy.freeze("GSUSPECT...", "court-order-2026-117");
await policy.clawback(TOKEN, "GSUSPECT...", 5_000n);                 // burn
await policy.clawback(TOKEN, "GLOSTKEY...", 100n, "GRECOVERY...");   // move

POLICY=$(stellar contract deploy --wasm target/wasm32v1-none/release/compliance_policy.wasm --source deployer --network testnet)
stellar contract invoke --id $POLICY --source deployer --network testnet -- initialize --admin <ADMIN>
stellar contract invoke --id <TOKEN> --source deployer --network testnet -- set_compliance_policy --new_policy "\"$POLICY\""

SDK

Types & Config

Contracts

Stellar modules

Reserve Attestation & Compliance

reserve-attestation — proof of reserve

compliance-policy — freeze, clawback, transfer rules

​reserve-attestation — proof of reserve

​compliance-policy — freeze, clawback, transfer rules

reserve-attestation — proof of reserve

compliance-policy — freeze, clawback, transfer rules