type BlockParsedSpotTrade_order struct {
    TokenS tdef.XTokenID // DA 2 bytes
    TokenB tdef.XTokenID // DA 2 bytes

    amountS *big.Int // DA 24 bytes ; You should use .FillS
    amountB *big.Int // DA 24 bytes ; You should use other-side .FillS

    NftData *NftData

    FeeBips uint16   // DA 1 byte
    FillS   *big.Int // DA 24 bytes ; the good one.

    ValidUntil tdef.ValidUntil // DA 32 bits
}

type AccountID uint32
type XTokenID uint16
type NftData [32]byte // 0x[hexa 64]
type ValidUntil uint32