Contract Actions

ERC20LazyVesting.sol is a smart contract for token vesting that utilizes off-chain Merkle proofs and on-chain validation to efficiently manage scalable vesting schedules. It allows beneficiaries or operators to claim vested tokens over time, based on predefined parameters encoded in Merkle trees.

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Dependencies

• OpenZeppelin Contracts:
  • AccessControl
  • ReentrancyGuard
  • Pausable
  • SafeERC20
• ERC20LazyVesting.interface.sol – Interface for defining the VestingSchedule struct and external function signatures.

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Contract: ERC20LazyVesting

• Inherits:

  • AccessControl
  • ReentrancyGuard
  • Pausable

• Uses SafeERC20 for secure ERC20 operations.

Functions

• release: Releases vested tokens to the beneficiary or an operator, based on a valid Merkle proof.
• getReleasedAmount: Returns how many tokens have already been released for a given schedule.
• getReleasableAmount: Calculates how many tokens are currently available for release based on time and schedule configuration.
• addValidMerkletreeRoot: Allows an operator to mark a Merkle root as valid (enables vesting for related schedules).
• revokeSchedules: Allows an operator to revoke one or more Merkle leaves, disabling further releases for them.
• requestWithdraw: Admin function to initiate the withdrawal process for any tokens remaining in the contract (starts a 30-day timer).
• withdraw: Admin function to execute withdrawal of tokens after the cooldown period ends.
• pause: Admin-only function to pause contract operations.
• unpause: Admin-only function to resume contract operations.

Internal / Private Functions

• _validateVestingSchedule: Validates a vesting schedule by computing and verifying its Merkle proof and root.
• _computeRoot: Computes the Merkle root based on a leaf and a proof path.
• _getReleasableAmount: Internal logic to calculate vested tokens depending on cliff, start, duration, and number of completed time slices.

Events

• Released: Emitted when tokens are released to a beneficiary.
• MerkletreeRootAdded: Emitted when a Merkle root is added or removed.
• SchedulesRevoked: Emitted when one or more vesting schedules are revoked.
• AnnounceTokensWithdrawal: Emitted when a withdrawal is requested.
• TokensWithdrawn: Emitted when tokens are successfully withdrawn after the announcement period.

Custom Errors / Validations

• Only the beneficiary or an account with OPERATOR_ROLE can call release.
• Schedules must pass Merkle proof validation and must not be revoked.
• Withdrawals can only occur 30 days after requestWithdraw is called.
• Only DEFAULT_ADMIN_ROLE can manage withdrawal, pause, or unpause.

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Notes

• Merkle tree-based design enables massive scalability for vesting schedules while keeping on-chain storage low.
• Supports revocable vesting and secure operator-controlled execution.
• Time-based vesting ensures fairness and compliance with distribution strategies.
• The contract can be paused by admins in case of emergencies.