Minting converts USDT into UNIT at one-for-one. It is one on-chain transaction preceded by one off-chain authorisation, and it settles in seconds.
The flow
1. Approve USDT. The Minter contract needs an allowance to pull USDT from your wallet. The app requests a standing allowance rather than a per-transaction one, so you approve once per wallet and not before every mint.
2. Verify. Your address is screened. One of three things happens:
- Cleared — an authorisation is signed and the app moves on.
- Declined on screening — you see a persistent notice with a risk score where one is available. No transaction is attempted and your USDT never moves.
- Temporarily unavailable — the check could not be completed. Try again later.
3. Mint. The transaction is submitted. The contract verifies the authorisation, pulls your USDT, routes it into the reserve, and mints UNIT to you.
Mint and stake in one transaction
The Stake UNIT automatically after minting checkbox folds staking into the same transaction. Without it you would mint, then approve UNIT to the vault, then deposit — three transactions and three fees. With it, one.
The choice is part of what gets signed, so it cannot be changed after the authorisation is issued.
What the authorisation covers
The signature is bound to five things, and any mismatch makes the contract reject it:
| Bound to | Effect |
|---|---|
| Your address | Cannot be used by another wallet |
| The amount | Cannot be reused for a larger mint |
| A nonce | Cannot be replayed — a second use reverts |
| A deadline | Expires; a late submission reverts |
| The Minter's address | Cannot be used against a different deployment |
This is why screening is a rule rather than a suggestion: the contract will not mint without a signature from a key the protocol controls, so calling it directly does not skip the check.
Rate and slippage
Minting is one-for-one. The transaction carries an output floor and reverts if it would deliver less. The app sets that floor 50 basis points (0.5%) below par on the mint leg, because the reserve route can return a hair under par between the moment the authorisation is issued and the moment the transaction lands. Redemption is held exact — see Redeeming UNIT.
If something fails
Most failures are one of four things: not enough TRX for fees, a screening decline, an expired authorisation, or a wallet that never confirmed. See Troubleshooting.