Reserve Infrastructure

Every dollar accounted for.

StableMMF maps the money market funds behind stablecoins — from T-Bill maturity schedules to real-time NAV attestation. Reserve transparency, not trust.


T2 · Reserves & Vaults

How deep does reserve verification run?

The big picture: Reserve verification is migrating from quarterly PDF attestations (policy-enforced, L5) toward on-chain NAV oracles (code-enforced, L3–L4). This Stack Diagram shows the compliance depth across three issuers.

COMPLIANCE DEPTH →Reserve Verification StackT2 Reserves & Vaults — where reserve verification mechanisms embed across issuersA-201 · SECTION CUTStableMMF.comUSDC / CircleBase (L2)USDT / TetherTRONPYUSD / PaxosEthereumL5APPLICATIONL4MIDDLEWARE / APIL3EXECUTIONL2CONSENSUSL1NETWORKSTATE TRANSITIONCircle TransparencyChainlink PoR FeedCircle Reserve Fund APIERC-4626 VaultBDO Italia AttestationTether Transparency PagePaxos Monthly AttestationPaxos Mint/Redeem APIGENIUS Act §4 DisclosureT2 Reserves & VaultsT7 Travel Rule & FilingGate (pre-condition)Monitor (concurrent)Obligation (post-settlement)Code-enforcedPolicy-enforced

Why it matters

$150B in reserves. One question: where is it?

The big picture: Stablecoin issuers hold more U.S. Treasuries than most sovereign nations. Money market funds are the vehicle — but transparency varies wildly.

  • Circle (USDC) — reserves in the Circle Reserve Fund managed by BlackRock. Weekly attestations, SEC-regulated 2a-7 fund
  • Tether (USDT) — quarterly attestation by BDO Italia. Mix of T-Bills, repo, secured loans. No single-fund structure
  • Paxos (PYUSD / USDP) — 100% cash and T-Bill equivalents. Monthly attestation. NYDFS-regulated trust
  • The gap: No unified standard for reserve composition disclosure, NAV tracking, or real-time proof of reserves
$150B+
Total stablecoin reserves
~80%
Held in T-Bills & repo
2a-7
SEC fund classification
$1.00
Target NAV per token

Reserve Composition

What backs the dollar peg.

Each issuer structures reserves differently. StableMMF normalizes the data into a comparable framework.

U.S. Treasury Bills

Short-duration sovereign debt

T-Bills with ≤ 90-day maturity. The safest, most liquid collateral. Preferred by GENIUS Act and MiCA frameworks.

Overnight Reverse Repo

Fed RRP facility access

Overnight collateralized lending to the Federal Reserve. Zero duration risk. Available to 2a-7 funds.

U.S. Agency Debt

FHLB & FFCB bonds

Government-sponsored enterprise debt. Slightly higher yield than T-Bills, minimal credit risk. Small portfolio allocation.

Cash Deposits

FDIC-insured bank accounts

Demand deposits at systemically important banks. Immediate liquidity for redemption spikes. Subject to FDIC limits.

Implementation

Chainlink Proof of Reserves — on-chain NAV verification.

How it works: Read the Chainlink PoR feed on Base to verify USDC reserve backing in real time — no trust in an auditor PDF required.

// POC 01 — Read Chainlink PoR feed on Base
import { createPublicClient, http } from 'viem';
import { base } from 'viem/chains';

const client = createPublicClient({
  chain: base,
  transport: http(),
});

// Chainlink PoR Aggregator for USDC reserves
const nav = await client.readContract({
  address: '0x...', // PoR feed
  abi: aggregatorV3ABI,
  functionName: 'latestRoundData',
});

// nav.answer → total reserves in USD (8 decimals)
// nav.updatedAt → last attestation timestamp
// Compare against USDC totalSupply:
const supply = await client.readContract({
  address: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913',
  abi: erc20ABI,
  functionName: 'totalSupply',
});

const ratio = Number(nav.answer) / Number(supply);
// → 1.0002 (fully backed)
Reserve Verification JourneyAgentic mint route — USDC on Base via Circle Reserve FundAGENTIC ROUTEGateMonitorObligationSCREENING & MONITORING ZONESTATE CHANGE← GATES & PRE-CONDITIONSOBLIGATIONS →S1IntentS2IdentityS3IntentS4NegotiationS5IntentS6IntentS7FacilitationS8FinalityAI AgentCircle VeriteChainlink PoRUSDC ContractAuditor / SEC

Regulatory Landscape

What the law requires.

What to know: Two major frameworks are converging on reserve quality requirements for stablecoin issuers.

  • GENIUS Act (U.S.) — requires 1:1 reserves in cash, T-Bills, or insured deposits. Monthly public disclosure. Issuer-level licensing
  • MiCA (EU) — mandates 60% minimum in bank deposits across diversified credit institutions. EMI or credit institution license required
  • NYDFS Trust Charter — Paxos model. 100% reserve ratio, monthly attestation by independent auditor, strict asset composition limits
  • SEC Rule 2a-7 — governs money market funds holding stablecoin reserves. Weighted average maturity ≤ 60 days, weekly liquid assets ≥ 30%

GENIUS Act

United States

Federal stablecoin framework. 1:1 reserve mandate with approved asset classes. Expected enforcement 2026.

MiCA

European Union

Markets in Crypto-Assets Regulation. Live since June 2024. EMT reserve rules for euro-referenced tokens.

NYDFS

New York

Trust company charter for Paxos, Gemini. State-level reserve and attestation standard since 2018.

Build sequence

Proof of concepts.

How it works: Every POC ships on Cloudflare Workers, calls a real API or reads an on-chain contract. No simulated demos.

POC 01 Coinbase CDP
Chainlink PoR Reserve Oracle
Read the Chainlink Proof of Reserve aggregator on Base via viem. Compare on-chain reserve attestation against USDC totalSupply to compute real-time reserve ratio. Same pattern as cbBTC PoR.
Live
POC 02 Circle Developer
Circle Mint Reserve Composition
Call the Circle Mint API to query institutional reserve composition — T-Bills, repo, cash breakdown. Normalize against USDT and PYUSD attestation data. Worker caches response in Cloudflare D1.
Building
POC 03 Cloudflare Workers
x402-Gated Reserve Data API
x402 middleware gates detailed reserve breakdowns behind USDC micropayments on Base. $0.001/query. Same pattern as Stable402 POC 01. Durable Object maintains live NAV state.
Building
POC 04 Coinbase CDP
BUIDL NAV Oracle Reader
Read BlackRock BUIDL tokenized MMF NAV from Base via Coinbase CDP. Track daily NAV per share, compare against USDC peg. Publish to D1 time-series.
Planned
POC 05 Circle Developer
Verite Credential-Gated Access
Circle Verite W3C Verifiable Credentials gate institutional access to detailed reserve data. Credential type: AccreditedInvestor. Verification via Catena ACK-ID DID resolver.
Planned
POC 06 Cloudflare Workers
DO NAV Tracker
Durable Object maintains per-fund NAV state. Ingests attestation events from Circle, Chainlink, and Paxos APIs. Exposes real-time WebSocket feed. Persistent SQL storage via DO SQLite.
Planned