Fees in Mean Finance are quite simple. We can divide them into two categories: gas fees and protocol fees.
Users only need to pay gas fees when they interact with their positions. This includes:
Creating their position
Modifying their position
Withdrawing their swapped balance
Terminating their position
Giving or revoking permissions
This means that users won't need to pay any gas for swaps. This network fee will be payed by swappers.
When users interact with their positions, no protocol fee is charged. Protocol fees are collected only on swaps. When a swap is executed, a protocol fee is collected from all users involved in that swap. As of now, that fee is 0.6%.
Let's try with an example using John's position:
Rate: 5 DAI
Swap interval: daily
Amount of swaps: 365
Let's assume that 4 swaps were executed, where 5 DAI = 1 ETH for all swaps. Now, John's swapped balance at the end of the forth swap would be 4 ETH. But, taking into account the protocol fee, it would actually be 4 - 0.6% = 3.976
It is important to mention that if John were to terminate the position at this point, he would get back:
The DAI what wasn't swapped: 361 * 5 = 1805 DAI
The ETH that was swapped: 3.976 ETH
See that no fee was charged from the balance that remained un-swapped.