function supplyDyDx(uint256 amount) public returns(uint) {
        Info[] memory infos = new Info[](1);
        infos[0] = Info(address(this), 0);

        AssetAmount memory amt = AssetAmount(true, AssetDenomination.Wei, AssetReference.Delta, amount);
        ActionArgs memory act;
        act.actionType = ActionType.Deposit;
        act.accountId = 0;
        act.amount = amt;
        act.primaryMarketId = 1;
        act.otherAddress = address(this);

        ActionArgs[] memory args = new ActionArgs[](1);
        args[0] = act;

        dydx.operate(infos, args);

        lender = CurrentLender.DYDX;
    }