> For the complete documentation index, see [llms.txt](https://docs.vetro.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.vetro.org/developers/smart-contracts.md).

# Smart Contracts

The core Ethereum contracts are implemented in **Solidity 0.8.30**.

## Core Contracts

### PeggedToken

ERC-20 with ERC-20Permit (gasless approvals), ERC-20Burnable, Ownable2Step ownership, address blacklisting, and designated Gateway/Treasury integration points. This contract serves as the template for VUSD, vetBTC, and vetETH.

### Gateway

Handles swap-ins, minting, redemption, and swap-outs with:

* Configurable fees and mint limits
* Slippage protection
* Multi-step redemption process with a governance-configurable security delay for standard users
* Instant redemption for whitelisted market makers against the Treasury buffer
* AMO mint limit enforcement

### Treasury

Manages collateral custody with:

* Per-token configuration (vault, oracle, staleness period, swap-in/swap-out toggles)
* Decentralized price feed integration with configurable tolerance bounds
* Keeper and UMM (Universal Mint Module) role separation
* Swapper integration for internal rebalancing
* OpenZeppelin AccessControlDefaultAdminRules for role-based permissioning

### StakingVault

ERC-4626 compliant vault implementing the sVUSD variable yield product. Features:

* Governance-configurable cooldown period for withdrawals (7 days → 1 day)
* Instant withdrawal whitelist for approved addresses
* Integration with the YieldDistributor for drip-based reward delivery

### YieldDistributor

Linearly drips yield to the StakingVault over a configurable duration to prevent yield sniping. When new yield is added, remaining undistributed yield is combined with the new amount and redistributed linearly — ensuring smooth price-per-share appreciation.

## Source Code

| Resource                             | Link                                                                                                                                            |
| ------------------------------------ | ----------------------------------------------------------------------------------------------------------------------------------------------- |
| GitHub Repository                    | [vetro-protocol/vetro-contracts](https://github.com/vetro-protocol/vetro-contracts)                                                             |
| Contract Source                      | [/src](https://github.com/vetro-protocol/vetro-contracts/tree/main/src)                                                                         |
| Documentation                        | [/docs](https://github.com/vetro-protocol/vetro-contracts/tree/main/docs)                                                                       |
| Operations Runbook                   | [OPERATIONS.md](https://github.com/vetro-protocol/vetro-contracts/blob/main/docs/OPERATIONS.md)                                                 |
| StakingVault & YieldDistributor Spec | [StakingVault-YieldDistributor-Spec.md](https://github.com/vetro-protocol/vetro-contracts/blob/main/docs/StakingVault-YieldDistributor-Spec.md) |


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