Instant Finality

**Future Work**

Because there's no need for a fee market or a replace-by-fee mechanism on Litheum it's possible to implement instant finality in a very simple way.

A sent transaction on Litheum can never be replaced once it's been signed and sent. in the case that a second transaction using the same nonce is produced, any actor with one of the transactions can submit it in the case where the other is added to a block in order to slash the wallet, claiming the fees associated with the transactions as well as a potential additional penalty (if the wallet has funds).

However this system only guarantees payment risk up to the value of the fee, however, any additional funds held by the wallet are potentially at risk, as the wallet would not be able to guarantee to remove those funds before they are slashed.

For any given block height a wallet is able to send transactions to a limited number of Transaction Runners. if the wallet user wishes to prove that a transaction has been sent to some other actor, that actor can simply query the mempool of those Transaction Runners to see if the transaction has been broadcast.

In the future, Litheum-specific wallets and block explorers will support the ability for users to understand the strength of finality for a given transaction.