ERC‑7518 (DyCIST) Reference Implementation

Dynamic Compliant Interop Security Token

This repository contains the reference implementation for ERC-7518, a security token standard that extends ERC-1155 to provide a flexible framework for managing compliant real-asset security tokens.

Overview

ERC-7518 introduces partitioned token management through the ERC-1155 multi-token paradigm, where each tokenId represents a distinct partition with its own set of rights, privileges, and compliance rules. This architecture enables management of tokenized real-world assets including fractional ownership, multiple share classes, and granular compliance controls. The standard also defines features like token locks, forced transfers, freezing, payouts, wrapping, and compliance hooks. (eips.ethereum.org)

Key Concepts from the EIP

• Partitions via tokenId: Enables semi-fungible tokens with partition‑specific logic.
• Compliance Hooks: Methods like canTransfer, lockTokens, forceTransfer, and freeze provide dynamic and enforceable rules.
• Payouts & Batch Payouts: Built-in functions for token‑holder distributions.
• Interoperability: Wrapping and unwrapping tokens, enabling cross‑chain or cross‑standard compatibility.
• Built on ERC‑1155 + ERC‑165: Ensures backward compatibility and easy integration with wallets and dApps.

Project Structure

erc‑7518‑foundry/
├── src/
│   ├── ERC7518.sol              # Core implementation
│   └── interfaces/
│       └── IERC7518.sol         # Interface contract
├── test/
│   └── ERC7518.t.sol            # Basic Foundry tests
├── script/
│   └── Deploy.s.sol             # Simple deployment script
├── lib/                         # Dependencies (e.g., OZ contracts)
├── foundry.toml
├── README.md
└── LICENSE

Core Features

Partition Management

• Each tokenId represents a unique partition with independent compliance rules
• Dynamic allocation of tokens between different classes or categories
• Support for temporary non-fungibility during regulatory holding periods
• Efficient management of complex asset structures within a single contract

Compliance Framework

• canTransfer() - Pre-transfer compliance validation
• restrictTransfer() / removeRestriction() - Dynamic transfer restrictions per partition
• freezeAddress() / unFreeze() - Account-level compliance actions
• Off-chain voucher support for dynamic compliance verification

Token Locking

• lockTokens() - Time-based token vesting and holding periods
• unlockToken() - Automated release after lock expiry
• transferableBalance() - Query available balance excluding locked tokens
• lockedBalanceOf() - Query locked token amounts

Recovery Mechanisms

• forceTransfer() - Authorized recovery for lost keys or compliance violations
• Bypass standard transfer restrictions for regulatory enforcement

Payout Distribution

• payout() - Single recipient distributions
• batchPayout() - Efficient multi-recipient payouts in single transaction

Interoperability

• wrapToken() / unwrapToken() - ERC-20 token wrapping
• Full backward compatibility with ERC-1155

Getting Started

Prerequisites

• Foundry installed (forge, cast).
• Solidity ≥ 0.8.x.

Deployment

# Install dependencies
forge install

# Build contracts
forge build

# Run tests
forge test -vvv

# Run gas snapshot
forge snapshot

# Deploy to network
forge script script/Deploy.s.sol --rpc-url <RPC_URL> --broadcast --verify

Testing

# Run all tests with verbosity
forge test -vvv

# Run specific test file
forge test --match-path test/ERC7518.t.sol

# Gas report
forge test --gas-report

Example Use Cases

• Fractional real estate classes: Define separate tranches (e.g., common vs. preferred) as partitions.
• Tranche-based finance: Different risk/return tiers represented by partition-specific token IDs.
• Cross-chain compliant RWAs: Tokens retain compliance state while moving across chains.

Guide

1. Implement compliance logic: Add canTransfer(...) checks using off-chain vouchers or on-chain registries.
2. Add recovery and lock features: Support token recovery via forceTransfer, and vesting via lockTokens.
3. Support freezing: Allow freeze() and unfreeze() on accounts or partitions.
4. Enable payouts: Safely distribute payouts using payout() and batchPayout().
5. Incorporate interoperability: Use wrapToken() and unwrapToken() for cross-chain or cross-standard compatibility.
6. Audit, document, license: Add comments, documentation, and choose a suitable open-source license (e.g., MIT).

License

This project is released under the GPL-3.0 License.

References

• EIP-7518 Specification
• ERC-1155 Multi-Token Standard
• ERC-165 Standard Interface Detection

Maintained by Zoniqx