dEURO

# Smart Contracts

A technical overview of all smart contracts powering the Decentralized Euro protocol.

The Decentralized Euro protocol consists of multiple smart contracts that work together to create a trustless, oracle-free stablecoin system. All contracts are deployed on Ethereum mainnet and are fully immutable - no admin keys, no upgrades, no central control.

# Contract Architecture

The contracts are organized into the following categories:

Category Purpose
Core Token contracts and reserve management
MintingHub Position management and collateralized minting
Savings Interest-bearing dEURO deposits
Bridges 1:1 conversion with trusted external EUR stablecoins
Gateways Frontend rewards and enhanced functionality (V2 only)

# Protocol Modules: V2 and V3

The dEURO contracts are immutable and cannot be replaced. Instead of upgrading via proxies, the protocol evolves by adding new modules through the standard suggestMinter() governance flow. The protocol currently runs two coexisting MintingHub and Savings module sets on Ethereum mainnet:

Module Status Frontend Rewards Notes
V2 Active, permanent Yes (via Gateways) Original launch modules; positions and savings opened here remain fully usable. Cannot be deactivated. Includes the CoinLendingGateway for native ETH lending.
V3 Active, permanent No Additional module set approved by nDEPS governance. Adds an updated savings/vault design and a price reference system. Routes do not pass through FrontendGateway.

Both module sets share the same dEURO token, the same nDEPS / DEPSwrapper governance pair, and the same Bridge contracts. New positions and savings deposits can be opened in either module; existing V2 positions are not migrated and continue to live under V2.

TIP

V3 is not a replacement for V2. It is an additional, parallel set of minter contracts that nDEPS holders approved through the standard governance application period. V2 remains the only home for positions and savings that were opened before V3 went live.

# Core Contracts

# Decentralized Euro (dEURO)

The main stablecoin token contract - an ERC-20 token designed to track the value of the Euro.

Key Features:

  • Implements ERC-20 and ERC-2612 (Permit)
  • Open to arbitrary minting plugins with veto-based governance
  • Creates the Equity contract during deployment
  • Manages the minter registry and position registry
  • Handles reserve accounting and loss coverage

Key Functions:

  • suggestMinter() - Propose a new minting contract (requires fee and application period)
  • denyMinter() - Qualified shareholders can veto minting proposals
  • mintWithReserve() - Mint dEURO with reserve contribution (minters only)
  • burnFromWithReserve() - Burn dEURO and reclaim proportional reserve
Property Value
Symbol dEURO
Decimals 18
Min Application Period 14 days
Min Application Fee 1,000 dEURO
Address 0xbA3f535bbCcCcA2A154b573Ca6c5A49BAAE0a3ea (opens new window)

# Equity (nDEPS)

The native equity token representing shares in the dEURO reserve pool. Holding nDEPS is similar to being a shareholder of a bank.

Key Features:

  • ERC-20 token with time-weighted voting power
  • 2% quorum required for governance veto
  • Price determined by proportional capital valuation (5x equity)
  • 2% fee on minting and redemption
  • 90-day minimum holding period before redemption is permitted (replaces the same-block redemption guard used in Frankencoin — the holding period subsumes the flash-loan attack surface)

Key Functions:

  • invest() - Mint nDEPS by depositing dEURO into the reserve
  • redeem() - Burn nDEPS to withdraw dEURO from the reserve
  • checkQualified() - Verify if an address has sufficient voting power (2%)
  • delegateVoteTo() - Delegate voting power to another address
  • kamikaze() - Sacrifice own votes to reduce malicious actor's votes

Voting Mechanics:

  • Votes accumulate over time: votes = balance * holdingDuration
  • Longer holding = more voting power
  • Delegation adds to delegate's power without removing own votes
Property Value
Symbol nDEPS
Decimals 18
Valuation Factor 5x (market cap = 5 × equity)
Quorum 2%
Min Holding Duration 90 days
Min Application Period (for suggestMinter) 14 days
Min Application Fee 1,000 dEURO
Min Equity 1,000 dEURO
Address 0xc71104001A3CCDA1BEf1177d765831Bd1bfE8eE6 (opens new window)

# DEPSwrapper (DEPS)

A standalone ERC-20 wrapper around nDEPS. Wrapping nDEPS into DEPS exchanges the voting/holding mechanics for free transferability:

  • nDEPS carries time-weighted voting power and resets the holding clock on every transfer.
  • DEPS is a plain ERC-20: transfer freely, hold custodially, deposit in AMMs, but no voting power until unwrapped.
  • Wrapping is 1:1 in both directions; the wrapper never touches the underlying economic value.
function wrap(uint256 amount) public
function unwrap(uint256 amount) public
function unwrapAndSell(uint256 amount) public returns (uint256)        // unwrap and immediately redeem via Equity
function halveHoldingDuration(address[] helpers) public                 // anti-vote-accumulation, requires 2% votes

unwrapAndSell() is provided as a convenience for redeeming directly into dEURO without first claiming the nDEPS to the caller's address. It bypasses the 90-day holding period of the underlying nDEPS as long as the wrapper itself has held them long enough on average and halveHoldingDuration() has not been called recently. Wrapping nDEPS into DEPS keeps the holding clock of the underlying nDEPS intact; unwrapping back to nDEPS, however, resets the recipient's holding clock as with any other transfer.

Property Value
Symbol DEPS
Decimals 18
Address (Mainnet) 0x103747924E74708139a9400e4Ab4BEA79FFFA380 (opens new window)
Address (Base) 0x5F674bF6d559229bDd29D642d2e0978f1E282722 (opens new window)

# MintingHub Contracts

# MintingHub

The central hub for creating, cloning, and challenging collateralized dEURO positions.

Key Features:

  • Creates new position contracts via PositionFactory
  • Manages Dutch auctions for liquidations
  • Handles forced sales of expired positions

Key Functions:

  • openPosition() - Create a new collateralized position (1,000 dEURO fee)
  • clone() - Clone an existing position with new parameters
  • challenge() - Start a Dutch auction to challenge undercollateralized positions
  • bid() - Place a bid in an ongoing challenge auction
  • buyExpiredCollateral() - Purchase collateral from expired positions

Challenge Process:

  1. Phase 1 (Aversion): Position owner can avert by buying challenger's collateral at liquidation price
  2. Phase 2 (Auction): Dutch auction where price decreases linearly to zero
Property Value
Opening Fee 1,000 dEURO
Challenger Reward 2%
Min Challenge Period 1 day

The protocol exposes two MintingHub modules. V2 is wrapped by MintingHubGateway for frontend-code tracking; V3 routes directly through MintingHub and adds an updated savings/vault design.

Module Address
V2 (MintingHubGateway) 0x8B3c41c649B9c7085C171CbB82337889b3604618 (opens new window)
V3 (MintingHub) 0x66AcC54a0C64255137b8993CB4972B0901684f7B (opens new window)

# Position

Individual collateralized debt position contract. Each position is a separate contract holding the user's collateral.

Key Features:

  • Immutable parameters set at creation (collateral type, reserve ratio, etc.)
  • Continuous interest accrual based on Leadrate + risk premium
  • Cooldown periods on price increases (3 days) for security
  • Can be denied by governance during initialization period

Key Functions:

  • mint() - Mint dEURO against deposited collateral
  • repay() - Repay debt (interest first in V3, then principal)
  • adjust() - All-in-one function to modify position parameters
  • adjustWithReference() (V3) - Same as adjust() but accepts a reference position that can waive the 3-day cooldown on a price increase
  • adjustPrice() / adjustPriceWithReference() (V3) - Change the liquidation price, optionally with a reference position
  • withdrawCollateral() / withdrawCollateralAsNative() (V3) - Withdraw excess collateral (native ETH variant available in V3)
  • deny() - Governance can deny positions during the init period

Interest Model:

Interest accrues continuously in both V2 and V3 — the up-front fee charged at mint time was a V1 (Frankencoin) characteristic that dEURO removed at launch. In both versions, principal and interest are tracked separately on the Position contract, and adjust(newPrincipal, …) lets owners change principal independently of the outstanding interest.

V3 changed the following relative to V2:

  • Native ETH/WETH is supported directly across MintingHub, Position and PositionRoller (V2 needs the CoinLendingGateway for the same).
  • Leadrate is integrated into MintingHub itself, so positions and savings consume the same rate source (V2 inherited Leadrate via Savings → SavingsGateway).
  • Interest is charged only on the usable mint (principal minus the part held back in the borrowers reserve), not on the full minted amount.
  • Reference positions can be passed to adjust*WithReference() to skip the 3-day cooldown on a price increase when another live position has already validated a higher price.
Property Value
Deployment Via PositionFactory (ERC-1167 clones)
Cooldown on Price Increase 3 days (V3: waivable via reference position)
Min Position Init Period 3 days (V2 and V3)
Rate base Leadrate at mint time + risk premium, re-synced to Leadrate whenever new tokens are minted into the position
Reference Position Mechanism (V3) adjustWithReference() / adjustPriceWithReference() accept a sibling position to skip cooldown when the new price is already validated elsewhere

# PositionFactory

Factory contract for deploying new Position contracts using the ERC-1167 minimal proxy pattern.

Key Features:

  • Creates new positions with full parameter set
  • Clones existing positions efficiently using minimal proxy
  • Validates position parameters before cloning

Key Functions:

  • createNewPosition() - Deploy a completely new position contract
  • clonePosition() - Create a minimal proxy clone of an existing position

Each MintingHub module owns its own PositionFactory.

Module Address
V2 0x167144d66AC1D02EAAFCa3649ef3305ea31Ee5A8 (opens new window)
V3 0x3a3985a96b1B51E6d914bc7C9e89fD6Ba6dEfE81 (opens new window)

# PositionRoller

Helper contract for rolling over debt from one position to another using flash loans.

Key Features:

  • Atomically moves debt and collateral between positions
  • Uses flash loans to avoid needing upfront capital
  • Preserves frontend codes when rolling through gateways

Key Functions:

  • roll() - Roll debt from source to target position with custom parameters
  • rollFully() - Roll entire position automatically

A PositionRoller can only roll between positions inside the same MintingHub module.

Module Address
V2 0x4CE0AB2FC21Bd27a47A64F594Fdf7654Ea57Dc79 (opens new window)
V3 0x5C22d5b752b2121faE7F6f0069252B03B2F7c5CD (opens new window)

# Savings Contracts

# Savings

Base savings module that enables interest-bearing dEURO deposits based on the Leadrate.

Key Features:

  • Interest accrues continuously based on Leadrate
  • No lockup period - withdraw anytime
  • Interest paid from system equity (profits)
  • Disabled when interest rate is zero

Key Functions:

  • save() - Deposit dEURO into savings
  • withdraw() - Withdraw dEURO and accrued interest
  • refreshBalance() - Collect accrued interest into balance
  • adjust() - Adjust savings to target amount

The protocol exposes two Savings modules. V2 is wrapped by SavingsGateway for frontend-code tracking; V3 routes directly through Savings and skips the FrontendGateway layer.

Module Address
V2 (SavingsGateway) 0x073493d73258C4BEb6542e8dd3e1b2891C972303 (opens new window)
V3 (Savings) 0x760233b90e45d186A9A98E911B115F7F4B90d3D9 (opens new window)

# SavingsVault (svDEURO)

ERC-4626 compatible vault adapter for the Savings module.

Key Features:

  • Standard vault interface for DeFi composability
  • Automatic interest accrual on deposits/withdrawals
  • Protected against inflation attacks via virtual shares
  • Tracks total claimed interest

Key Functions:

  • deposit() - Deposit dEURO and receive vault shares
  • withdraw() - Burn shares and receive dEURO with interest
  • price() - Current price per share
  • totalAssets() - Total dEURO including accrued interest
Property Value
Symbol svDEURO
Standard ERC-4626

Each Savings module ships with its own SavingsVault adapter.

Module Address
V2 0x1e9f008B1C538bE32F190516735bF1C634B4FA40 (opens new window)
V3 0x75Beb37A3C86eE4c38931E2a9319E078da612979 (opens new window)

# Leadrate

The governance-controlled base interest rate of the system. Leadrate is an abstract base contract: in V2 it is inherited via Savings → SavingsGateway, and in V3 the V3 MintingHub inherits it directly so positions and savings consume the same rate.

Key Features:

  • Qualified nDEPS holders can propose rate changes
  • 7-day timelock on all rate changes
  • Tracks accumulated "ticks" for interest calculations
  • Used by both Savings and Position contracts

Key Functions:

  • proposeChange(uint24 newRatePPM, address[] helpers) - Propose a new interest rate (requires 2% voting power)
  • applyChange() - Execute a pending rate change after 7 days
  • currentTicks() - Get accumulated interest ticks since deployment
Property Value
Rate Format PPM (parts per million) per year
Timelock 7 days
Initial V2 rate 10% (100000 PPM)
Initial V3 rate 8% (80000 PPM)

# Bridge Contracts

# StablecoinBridge

Enables 1:1 conversion between trusted external EUR stablecoins and dEURO.

Key Features:

  • Mints dEURO by depositing source stablecoins
  • Burns dEURO to retrieve source stablecoins
  • Has maximum limit and expiration horizon

Key Functions:

  • mint() - Convert source stablecoin to dEURO
  • burn() - Convert dEURO back to source stablecoin

# EUR Stablecoin Bridges

Bridges whose horizon has passed are expired: minting reverts, burning dEURO back into the underlying stablecoin keeps working. Status as of the on-chain horizon() values (see Swap for details):

Source Bridge Address Underlying Token Status
EURT 0x2353D16869F717BFCD22DaBc0ADbf4Dca62C609f (opens new window) 0xC581b735A1688071A1746c968e0798D642EDE491 (opens new window) Expired 2025-04-03
EURS 0x73f38ca06b27eaefb1612d062d885f58924f5897 (opens new window) 0xdb25f211ab05b1c97d595516f45794528a807ad8 (opens new window) Active until 2026-11-05
VEUR 0x76d8f514554a4a8e5d6103875f2dd7a67543692b (opens new window) 0x6ba75d640bebfe5da1197bb5a2aff3327789b5d3 (opens new window) Active until 2026-11-05
EURC 0xB4fF7412f08C22d7381885e8BdA9EE9825092fd1 (opens new window) 0x1aBaEA1f7C830bD89Acc67eC4af516284b1bC33c (opens new window) Active until 2026-09-05
EURR 0x20B0a153fF16c7B1e962FD3D3352A00cf019f1a7 (opens new window) 0x50753CfAf86c094925Bf976f218D043f8791e408 (opens new window) Expired 2025-10-22
EUROP 0x3EF3d03EFCc1338d6210946f8cF5Fb1a8b630341 (opens new window) 0x888883b5F5D21fb10Dfeb70e8f9722B9FB0E5E51 (opens new window) Expired 2025-10-22
EURI 0xb66A40934a996373fA7602de9820C6bf3e8c9afE (opens new window) 0x9d1A7A3191102e9F900Faa10540837ba84dCBAE7 (opens new window) Expired 2025-10-22
EURE 0x4dfd460d54854087af195906a2f260aa483a13b1 (opens new window) 0x3231Cb76718CDeF2155FC47b5286d82e6eDA273f (opens new window) Active until 2026-11-05
EURA 0x05620F4bB92246b4e067EBC0B6f5c7FF6B771702 (opens new window) 0x1a7e4e63778b4f12a199c062f3efdd288afcbce8 (opens new window) Expired 2026-01-15

# Gateway Contracts

V2 ONLY

The Gateway layer only exists in V2. V3 modules (MintingHub, Savings) bypass the Gateway pattern entirely and do not emit frontend rewards. Frontend operators only earn rewards on V2 activity.

# FrontendGateway

Manages frontend referral codes and distributes rewards to frontend operators.

Key Features:

  • Frontend operators register unique codes
  • Rewards distributed based on user activity
  • Covers investments, savings, and minting
  • Governance-controlled fee rates with 7-day timelock

Key Functions:

  • registerFrontendCode() - Register a new frontend code
  • invest() - Invest in nDEPS with frontend reward
  • redeem() - Redeem nDEPS with frontend reward
  • withdrawRewards() - Claim accumulated frontend rewards
  • proposeChanges() - Propose new fee rates (requires 2% votes)
Activity Rate
Investment / Redemption 1% of volume
Savings interest 5% of interest earned
Minting interest 5% of interest paid
Property Address
Mainnet 0x5c49C00f897bD970d964BFB8c3065ae65a180994 (opens new window)

# CoinLendingGateway

The V2 minting hub only accepts ERC-20 collateral. To open a leveraged position backed by native ETH without first wrapping it manually, the CoinLendingGateway (V2 only) takes ETH via msg.value, wraps it to WETH internally, clones a parent WETH position, and transfers ownership to the user. It also exposes a price-adjusted clone flow for setting a custom liquidation price in the same transaction.

Key Features:

  • Accepts native ETH directly (no manual WETH wrapping)
  • Clones the parent position and transfers ownership atomically
  • Optionally adjusts the liquidation price during clone (price adjustment in the same tx)
  • Routes through MintingHubGateway, so frontend codes are preserved

V3 has no equivalent: the V3 MintingHub and PositionRoller support native ETH directly via their *Native variants and payable functions, removing the need for a separate gateway.

Property Address
Mainnet (V2 only) 0x1DA37D613FB590eeD37520b72e9c6F0F6eee89D2 (opens new window)

# Contract Summary

# Shared

Contract Address Purpose
dEURO 0xbA3f...3ea (opens new window) Main stablecoin token
nDEPS (Equity) 0xc711...EE6 (opens new window) Reserve pool shares with voting
DEPS (Wrapper) 0x1037...380 (opens new window) Transferable wrapper for nDEPS

# V2 Module (active, with frontend rewards)

Contract Address Purpose
MintingHubGateway 0x8B3c...618 (opens new window) Position management hub (V2)
PositionFactory 0x1671...5A8 (opens new window) Position deployment factory (V2)
PositionRoller 0x4CE0...c79 (opens new window) Position rollover helper (V2)
SavingsGateway 0x0734...303 (opens new window) Savings with frontend rewards
SavingsVault 0x1e9f...A40 (opens new window) ERC-4626 savings vault (V2)
FrontendGateway 0x5c49...994 (opens new window) Frontend reward system (V2 only)
CoinLendingGateway 0x1DA3...9D2 (opens new window) Native ETH lending gateway (V2 only)

# V3 Module (active, no frontend rewards)

Contract Address Purpose
MintingHub 0x66Ac...4f7B (opens new window) Position management hub (V3)
PositionFactory 0x3a39...FE81 (opens new window) Position deployment factory (V3)
PositionRoller 0x5C22...c5CD (opens new window) Position rollover helper (V3)
Savings 0x7602...d3D9 (opens new window) Savings module (V3)
SavingsVault 0x75Be...2979 (opens new window) ERC-4626 savings vault (V3)

# Layer 2 Deployments

dEURO is canonically minted on Ethereum mainnet. Bridged token contracts mirror the supply on Layer 2 networks via the OP Stack standard bridge (0x4200000000000000000000000000000000000010). See Bridge to other Chains for the bridging UX.

Chain Token Address
Optimism dEURO 0x1B5F7fA46ED0F487F049C42f374cA4827d65A264 (opens new window)
Base dEURO 0x1B5F7fA46ED0F487F049C42f374cA4827d65A264 (opens new window)
Base DEPS 0x5F674bF6d559229bDd29D642d2e0978f1E282722 (opens new window)

# Security Properties

The dEURO smart contracts are designed with the following security properties:

Property Implementation
Immutability No admin keys, no proxy upgrades
Oracle-free No reliance on external price feeds
Flash loan protection 90-day minimum holding period on nDEPS makes flash-loan governance attacks impossible
Governance timelocks 7-14 day delays on critical changes
Minority protection 2% veto threshold
Bridge expiry Every bridge winds down automatically at its horizon
Inflation attack mitigation ERC-4626 virtual shares pattern

# Source Code

All smart contract source code is available on GitHub:

Repository: github.com/d-EURO/smartContracts (opens new window)

Network Chain ID Explorer
Ethereum Mainnet 1 etherscan.io (opens new window)
Base 8453 basescan.org (opens new window)
Optimism 10 optimistic.etherscan.io (opens new window)

# Complete Function Reference

For a comprehensive listing of every public function across all contracts — full signatures, parameters, return values, events — see the Smart Contract Functions Reference.