Helsing: Private masternode staking in Lelantus Spark

helsing-1049371.pdf (241.1 KB)

We are proud to unveil our proposal for Helsing, a method to enable private masternode staking in Firo. Masternodes in Firo perform several important functions such as securing the chain against 51% attacks via ChainLocks and also enabling quick finality of transactions within a few seconds.

To provide resistance against Sybil attacks, a collateral of 1000 FIRO is staked to encourage honest behaviour of the masternode and this needs to be verified by the rest of the network. Our upcoming privacy protocol, Lelantus Spark, greatly improves privacy by hiding amounts, when funds come in and also when they are moved out. Therefore there needs to be a different method of determining whether the collateral is present while preserving privacy.

Helsing (named after Van Helsing), allows users to stake their 1000 FIRO within Spark and prove that the collateral is present and not moved within Spark without revealing the source of the coins being staked. Helsing also allows masternode payouts to be paid directly to Spark addresses directly anonymizing them.

Why Helsing?

As a privacy centric coin, we want Spark and Spark addresses to be the default way FIRO is used and reduce the reliance on transparent addresses as part of our efforts to phase them out. Masternodes form a key component of our blockchain network and Helsing enables masternode collaterals to be held in the Spark pool and payouts to be directly anonymized. Anonymized masternode payouts increase the overall Lelantus Spark anonymity set and protects the privacy of masternode holders by preventing such funds from masternode rewards from being tied to masternodes.

When is Helsing going live?

The current plan is to deploy Lelantus Spark on Firo’s mainnet first (estimated Q2 2022) before implementing Helsing after. As Helsing is still a work in progress and still pending formal and external review this gives us time for feedback, comments and suggestions from the Firo community and wider technical community. We look


This project never ceases to innovate and increase the privacy preserving features available to FIRO users. It has got me more fired up about the release of Lelantus V2 AKA Lelantus Spark. I think that people will really have to start taking notice of the FIRO project; at that stage it will be well ahead of Monero in practical privacy terms.

The one question that this Helsing development raised for me was to do with regulatory pressure on privacy coins. Sometimes it is advantageous to know the provenance of a coin, especially a freshly mined one. Will it be possible, with Helsing enabled, to prove to a CEX that the FIRO you are depositing with them have come from MN earnings? The same question could be asked by POW miners as well of course.


You can always provide view keys to show outgoing so I believe it’s possible.

PoW Miners directly earn from coinbase so it’s not subject to shielding but we may want to have it such that all mined coins directly have to go into the shielded pool.

What is the status of Helsing?
Can we now create a masternode in Lelantus Spark? Where are the instructions?
What will be the status of Helsing after Lelantus is retired?

We’re focusing on Spark and deploying it and then we’ll see if we would then proceed to Helsing. The main thing we are concerned is whether masternodes are the way to go in the long term as a consensus mechanism.

So Helsing is not operational? Masternodes can only be hosted with transparent funds?
Is not consensus handled by masternodes and miners currently?

Helsing is not operational because it requires Spark and Spark is undergoing code audit and not yet deployed on mainnet yet.

You still can have more or less anonymous masternodes (from the point of view of funds) since when you do a Lelantus spend or Spark spend to transparent there is no known sender/source for the 1000 FIRO. After all, in masternodes, everyone knows that you are holding 1000 FIRO there so there’s no need to ‘hide’ the amount.

The main purpose of Helsing is when we move further into the Spark ecosystem we want ways to fully remove the requirement of transparent addresses and Helsing enables this.

Consensus is being handled by masternodes and miners currently but we are exploring whether we further want to entrench into the masternode ecosystem or to explore more decentralized mechanisms that do not need fixed IP infrastructure.
I do believe that Helsing can still be used in other consensus mechanisms as well where there is a need to prove ‘stake’.