//thruster-protocol/thruster-cfmm/contracts/ThrusterPair.sol
    function mint(address to) external lock returns (uint256 liquidity) {
...
        if (_totalSupply == 0) {
            liquidity = Math.sqrt(amount0.mul(amount1)).sub(MINIMUM_LIQUIDITY);
            _mint(address(0), MINIMUM_LIQUIDITY); // permanently lock the first MINIMUM_LIQUIDITY tokens
        } else {
            liquidity = Math.min(
                amount0.mul(_totalSupply) / _reserve0,
                amount1.mul(_totalSupply) / _reserve1
            );
        }
        require(liquidity > 0, "ThrusterPair: INSUFFICIENT_LIQUIDITY_MINTED");
        _mint(to, liquidity);
...
