ERC20 Token Distribution

(cliff and lockup here used interchangeably)

Deploys OpenZeppelin's TokenVesting Contract with the given recipient, start time, lockup duration, vesting duration, and revocability.

Filling the contract

After deployment, the contract needs to be sent the tokens to vest.

Vesting schedule

The vesting schedule is defined by 3 parameters (in seconds):

• Start: time at which both the lockup and vesting period start counting
• CliffDuration: lockup duration; i.e. elapsed time after Start, before which no assets are withdrawable, and after which any vested assets are withdrawable
• Duration: length of the vesting period; i.e. elapsed time after Start, after which all assets will be vested

ℹ️ For a "first monthly tranche" to be available right after the cliff elapses, Start should be 1 month before the first expected tranche, and CliffDuration should be 1 month.

⚠️ Vesting is done not monthly, but every second. This means that, once the cliff elapses, tokens can be withdrawn as frequently as desired.

Example

⚠️ In this example, 1 month = 30 days

For 100 FCL, 3 month lockup after 2021.02.25, 3 months vesting, and a "first monthly tranche" available after cliff:

• Start: 1619395200 (2021.04.26, 2 months after 2021.02.25)
• CliffDuration: 2592000 (30 days, during which the first tranche vests)
• Duration: 10368000 (4 months: vesting + 1)

⚙️  Distribution parameters

	Amount:  100 FCL
	Lockup:  3 months
	Vesting: 3 months

	➡️  Tranches: 4 (ca. 25 FCL each)
	➡️  1st tranche due: 2021.05.26


⚙️  Contract parameters

	start:             1619395200 (2021.04.26: 1 month before first contract tranche due)
	cliffDuration:        2592000 (1 month: during which 1/4 vests)
	duration:            10368000 (4 months: vesting + 1)

	➡️  cliff ends:     2021.05.26
	➡️  vesting ends:   2021.08.24


🔮 Distribution simulation

	🗓  Before lockup ends

	2021.05.23:              0 FCL
	2021.05.24:              0 FCL
	2021.05.25:              0 FCL

	🗓  After lockup ends

	2021.05.26:             25 FCL (tranche  1 / 4: 25 FCL)
	2021.06.25:             50 FCL (tranche  2 / 4: 25 FCL)
	2021.07.25:             75 FCL (tranche  3 / 4: 25 FCL)
	2021.08.24:            100 FCL (tranche  4 / 4: 25 FCL) ✅

Deploying

Uses Hardhat, as recommended in OpenZeppelin's Deploying and interacting guide.

1. cp .env.example .env and adapt
2. Adapt scripts/deploy.js
3. npx hardhat run scripts/deploy.js --network <rinkeby|mainnet>

Interacting

You can use the Hardhat console. The contract's address is output by the deployment script, and its ABI can be found at ./artifacts/contracts/TokenVesting.sol/TokenVesting.json.

[signer] = await ethers.getSigners()
contract = new ethers.Contract(address, abi, signer)
contract.release("0xTokenAddress")
contact.unpause()

Verifying in Etherscan

Uses Hardhat's Etherscan plugin.

1. Set ETHERSCAN_API_KEY in your .env file
2. Adapt arguments.js
3. Run npx hardhat verify --network <rinkeby|mainnet> --constructor-args arguments.js <contract address>