CCTP One — native USDC across chains

An independent interface for moving native USDC between Solana and EVM chains with Circle CCTP V2. Users can self-claim with a destination wallet to avoid the Orbit fee, or choose Circle Orbit for automatic destination minting. The app runs on CCTP mainnet only.

Run locally

pnpm install
pnpm dev

Build the production bundle with pnpm build. Run pure unit tests with pnpm test.

Included

• All 23 USDC mainnets currently exported by Circle Bridge Kit: Arbitrum, Avalanche, Base, Codex, Cronos, EDGE, Ethereum, HyperEVM, Injective, Ink, Linea, Monad, Morph, OP Mainnet, Pharos, Plume, Polygon PoS, Sei, Solana, Sonic, Unichain, World Chain, and XDC
• Wallet Standard auto-discovery for Solana wallets such as Backpack, Phantom and Solflare
• EIP-6963 EVM wallet discovery for explicit MetaMask, Rabby, and Coinbase Wallet selection (with legacy fallback and account/chain change disconnect)
• Self-claim mode with destination-wallet mint signing, no Orbit fee, destination gas preflight, and automatic Solana ATA creation
• Optional Orbit automatic-mint mode with protocol vs Forwarding Service fee breakdown and an execution-bound maxFee
• 60-second quote expiry plus immediate pre-signing USDC and buffered native-gas balance rechecks
• Canonical source-account USDC balance preflight and 6-decimal amount validation
• Solana destination ATA preflight (Self-claim can create a missing ATA; Orbit requires an existing ATA)
• Real CCTP V2 mainnet burn → attest → mint execution
• Fast and Standard transfer modes, enabled per source chain from Circle's capability matrix and validated against Bridge Kit definitions
• Per-destination Forwarding Service capability checks; unsupported Orbit destinations automatically remain in Self-claim mode
• Step-by-step BridgeResult persistence for in-browser resume + kit.retry (forwarder-safe)
• Transaction explorer links and beforeunload protection while a transfer is in flight
• Solana Lookup Table authority scanning, exact cooldown tracking, two-stage deactivate/close signing, and rent recovery

Networks

Routes use Circle Bridge Kit mainnet chain definitions. For Solana, set a dedicated RPC endpoint before use. Mainnet routes involving Solana are disabled when VITE_SOLANA_MAINNET_RPC is not configured:

cp .env.example .env
# edit:
VITE_SOLANA_MAINNET_RPC=https://your-solana-mainnet-rpc.example

Never place private keys or RPC secrets in VITE_* variables. Browser-visible variables are public.

Local integration harness files under .tmp/ (wallets, keypairs) are gitignored. Do not commit them.

Transfer recovery

Before signing, and after every Bridge Kit step, the app stores a versioned full BridgeResult in localStorage (relay:last-transfer:<env>). Incomplete transfers can be resumed with Resume transfer when:

1. The same browser profile still has the snapshot
2. The source wallet is reconnected
3. The snapshot includes provider + chain + step data (v2 format)
4. The connected wallet address and source chain exactly match the saved transfer

Legacy summary-only snapshots remain inspectable (explorer links) but are not auto-retryable.

Forwarder retries call kit.retry(result, { from: sourceAdapter, to: undefined }). Self-claim retries require both the original source adapter and the original destination claim adapter.

External manual claim

Manual claim can finish a CCTP V2 burn started in another app or browser. Select the burn's source chain and paste its source transaction hash/signature. The app reads Circle's attested message, derives the destination chain and fixed mint recipient, then asks a destination-chain wallet to submit only the mint.

Burns with an active Circle Orbit forward, or a destinationCaller restricted to another relayer, cannot be manually claimed here. Fast Transfer attestations are re-attested after expiry. Solana destinations additionally require VITE_SOLANA_MAINNET_RPC and the recipient wallet whose USDC ATA is encoded in the burn; the connected claim wallet pays SOL and can create that ATA.

Production warning

This app can move real USDC and spend real gas. Before relying on this as a public fallback service, add durable off-device transaction storage, multi-RPC failover, analytics/monitoring, compliance controls, broader end-to-end tests, and an independent smart-contract/frontend security review.

For a first mainnet smoke test: use a dedicated source wallet and RPC, request a fresh quote, and choose an amount whose displayed Receive value is greater than zero. In Self-claim mode, fund the destination claim wallet with its native gas token. In Orbit mode, use the live quoted Forwarding Service fee rather than a hard-coded test amount. Keep the tab open through mint and verify the source burn, destination mint, recipient address, and destination balance.