How do you optimize transaction fees?

We use multiple techniques to make fees lower.

Some of them are:

• Batching multiple actions together in one transaction - for example, to deposit into Yearn normally you'd need to approve Curve, deposit into Curve, approve Yearn, deposit into Yearn - 4 transactions. By batching these together, we eliminate 3 payments of the base gas (21000).
• Smart adjusting of gas price parameters - we use historical data to adjust the post-EIP1559 Base Fee and Tip, leading to quick inclusion for less cost.
• Using Flashbots/Eden for private transactions - private transactions actually cost a bit more in terms of gas price, but they do stop you from being sandwiched or front ran in trades. We only use those private APIs if needed. The way they work is by relaying transactions directly to the miners rather than broadcasting them in a public mempool, where greedy bots wait to take advantage.