Taker fees are the same, 0.125%, regardless of the type of liquidity matched against. Takers don’t have to worry about or differentiate between different liquidity types as the impact to them is the same.
When taking limit order liquidity, all of the 0.125% taker fee is collected as protocol fees. When taking pool liquidity, 0.10% of the fee is sent to the pool as compensation for liquidity providers. The remaining 0.025% is collected as protocol fees.
IDEX HL automatically manages gas rates for users to minimize costs and eliminate failed trades and front running attacks. IDEX users pay gas fees directly in order to move their funds into the IDEX smart contracts. Gas fees for subsequent transactions (trade, liquidity addition/removal, withdrawals) are deducted from the user’s balance to offset settlement gas costs, similar to the collection of trade fees.
Trade Settlement - Paid for by the taker. Computed based on the current gas price and deducted from the amount of asset received by the taker.
Withdrawal - Computed based on the current gas price and deducted from the amount of asset withdrawn to the wallet. For more on IDEX withdrawals, see here.
Liquidity Addition & Removal - Liquidity changes are sequenced in the trading engine and dispatched by IDEX, and thus gas fee reimbursement is necessary. Fees are collected addition/removal based on the current gas price and deducted proportionally from the reserve quantities of the addition or removal.