* relayer
* design
* race condition ? (sequencer or something)
* the current trusted setup is not secure ?

How we do transaction inside pool of A amount.
1. sort inputs by amount
2. try to take 1 or 2 smallest inputs to satisfy A amount. Get 16 inputs if it's not possible using the same way
3. Also you can always use transaction to merge your inputs with change (especially in 16 inputs case)