USDT0 Deployment & Configuration Verification
Deployment verification case study
“We very much appreciate Guardian’s approach to security and the entire audit process. Guardian goes above and beyond to not only do manual audits but also contribute to verification processes and helps for the entire development pipeline to improve.”
Core TeamUSDT0
Overview
Since February 2025 Guardian has verified every step of USDT0's omnichain rollout: new chain deployments, peer wiring, DVN and gas configuration, migrations, delistings and the multisig transactions that carry them out. More than forty-five engagements to date, across four Tether assets and three virtual machines.
Guardian
Guardian provides institutional-grade security for digital asset teams, onchain and off. Every engagement runs two independent teams, backed by Helix, Guardian's AI auditor, and only human-verified findings reach the client.
USDT0
USDT0 is the omnichain deployment of Tether's USDT, built on LayerZero's OFT standard and live on more than 25 chains, with over $150B in volume. The same architecture now carries XAUT0 (Tether Gold), USAT and CNHT0.
Why deployment verification is its own discipline
An audited contract can still be deployed wrong. Connected to the wrong peer, owned by the wrong address, configured with the wrong DVNs or migrated with the wrong transaction, a correct contract becomes an unbacked token or an unrecoverable transfer. Every new chain is another chance to make that mistake, and USDT0 was adding chains every few weeks.
Guardian had audited the OFT architecture itself in January 2025, so each deployment could be verified against a precise understanding of what correct looks like.
What Guardian verifies
- Bytecode: deployed proxies, implementations and admins matched byte-exact against the audited source
- Ownership and roles: every privileged address confirmed against the intended multisig
- Peers and DVNs: each chain's peers, DVN sets, confirmation counts and enforced gas checked for every pathway
- Transactions: every queued Safe and OneSig transaction decoded and simulated before execution
- Fork tests: end-to-end tests against live mainnet state with real deployment parameters
- Migrations and exits: supply migrations, ownership migrations and network delistings verified before they run
The scale of it
USDT0 deployments on Flare, Sei, Corn, Rootstock, XLayer, Polygon, Conflux, Monad, Mantle, MegaETH, Morph, Tempo, Hedera and Stellar; XAUT0 on Plasma, Ink, Celo, Solana, BSC, Conflux and Stable; USAT on Ethereum and Celo; CNHT0 on Conflux. Around them sit the wiring reviews, peer verifications, configuration changes and canary-chain transaction checks that keep an omnichain mesh consistent as it grows.
Most of it is public: over a dozen chains have a Guardian deployment report in the client's own audit repository.
Results
The clearest example came on Polygon in August 2025. The contracts were correct; the migration playbook was not. The queued transactions would have left more USDT0 circulating across LayerZero chains than there was USDT backing it. Guardian flagged it and it was fixed before the transactions ran. The report is public.
USAT, Tether's US-regulated stablecoin, shows the standard applied end to end: proxy, implementation and admin bytecode matched byte-exact on two networks, ownership confirmed, and a 62-test fork suite over blocklist, permit, mint and redeem paths, all passing.
- 45+ deployment, configuration and verification engagements, February 2025 to September 2026
- 25+ chains across EVM, Solana and Stellar
- 4 Tether assets: USDT0, XAUT0, USAT and CNHT0
Impact
- Every rollout reviewed before it went live, not audited after the fact
- A supply-unbacking migration caught before execution
- One verification standard applied consistently across every chain, asset and virtual machine
Read the full relationship in the USDT0 client story.
Deploying across many chains? Guardian verifies every deployment, wiring and transaction before it ships.