Implementation of Sapling + VaultZ Proposal at 5.00% Blockchain Reward


This post will outline the necessary steps required to execute the VaultZ proposal. It is meant to be an all encompassing detail focused publication of the efforts required, and to be undertaken by the team, to carry the VaultZ proposal from planning through execution, implementation, and monitoring phases.

Additionally, we will be required to update to at least Groth16 proving method, over the past weeks @renuzit has worked tirelessly to implement zcash core updates into BitcoinZ. Read further for more details.

For details on the VaultZ proposal please see:

VaultZ Proposal
Percentage for VaultZ

For details on the zkSNARKs Sprout vulnerability please see:

BitcoinZ Current zkSNARKs Proving Method

Meeting Type Date Discussion
Preliminary Sept 30th, 2018 General discussion regarding efforts required for proposal implementation
Plan / Identify Nov 3rd, 2018 Discuss beginning of testing phase and required components; as well as any obstacles and discoveries during self-testing / code review
Notes: Created todo list
Reached out to exchanges to determine support (pending responses)
Discussed when sapling integration would make most sense
Discussed ‘DynamicZ’ - a StealthWerkZ project
Identified critical testing components: Testnet node, Explorer, Pools, Replay protection
Re-introduce community fee code into core node
Preliminary timeline for minimal functional testing: 2-4 weeks
Update required to Groth16 zkSNARKs proving method at a minimum / Sapling codebase
Execution March 1st, 2019 Begin deploying test environments for testing of block reward change; and any components required for minimal functionality
Notes: COMPLETED : Sapling + VaultZ Master branch Github
COMPLETED : Testnet Pool:
COMPLETED : Testnet Explorer: Iquidus / Insight
COMPLETED : Re-introduce community fee code into core node
Next steps: Wallet systems: Win Binaries, Copay, etc
March 17th, 2019
1. shielded coinbase coins using z_shieldcoinbase" from multisig one -
“t2FpKCWt95LAPVRed61YbBny9yz5nqexLGN” to a sapling z-address
2. sent from sapling z address to single wallet tmQaL15dnng34TNknZiedx9qjRpaHihJMT6
3. sent from t single wallet tmQaL15dnng34TNknZiedx9qjRpaHihJMT6 to sprout z-address
4. sent from sprout z-address to tmQaL15dnng34TNknZiedx9qjRpaHihJMT6
5. tried to send between Sapling -> Sprout and was denied, as it should be denied
6. Mined blocks and the 5% block reward split is being sent to community fee addresses as intended
March 24th, 2019
Production release: Activation on April 6/7th @ Block 328,500
BitcoinZ v2.0.3 (Sapling + VaultZ) - Debian, Linux x64, Windows CLI x64
BitcoinZ v2.0.3 Win GUI Wallet
Notes: PENDING: Insight Explorer, CoPay Wallet, Web Wallet, Paper Wallet sites
Notes: These systems will be ready by the activation height
Partially moving to Implementation phase
Implementation March 23rd, 2019 Network updates completed:
Iquidus Explorer
Seeder nodes
Windows GUI Swing wallet
Coinomi Wallet ZelCore Wallet CoPay
Web wallet
Pending network updates:
Paper Wallet
Monitoring April 7th, 2019 Upgrade activated (VaultZ + Sapling) now active
Execution plan completed April 7th, 2019 Execution plan completed and fully deployed. Thread will be locked.

Components Identified

During the preliminary meeting BTCZ devs identified the components below.

Coordination / with the listed components will be required at least 30 days before Implementation is foreseeable.

The message needing to be communicated to the components listed is simple: If you’re running a full node for any purpose, an update to latest node build from BTCZ Github is required when it is available.

NOTICE: This list is not considered exhaustive - If any component is missing/not listed please let us know by posting in this thread, tweeting us, getting us on Discord or email us at [email protected]


  2. BTC - Alpha
  3. Crex24
  4. Exmo
  5. Exrates
  6. Graviex
  8. STEX (stocks exchange)
  9. TradeSatoshi


  1. Equipool
  2. PCMining
  3. Axepool
  4. Geekhask
  5. Mineflow
  7. CryptoCommunity
  8. Miningspeed
  9. Zsolo
  10. Nibiru Pool
  11. Altpool
  12. 2Miners
  13. Coinblockers
  14. Supernova


  1. Co-pay - will update when Insight explorer / BWS updated

  2. Multi-asset wallets:
    a. Coinomi - node update required
    b. ZelCore - node-update required?

  3. Swing wallet - node re-packaging required

  4. CLI wallet - update node build required

  5. Web wallet - will update when Insight explorer is updated

  6. Offline wallets / paper wallet sites - no update required


  1. Iquidus - node update required

  2. Insight - node update required / many other updates

NOTICE: This list is not considered exhaustive - If any component is missing/not listed please let us know by posting in this thread, tweeting us, getting us on Discord or email us at [email protected]

Updated March 17th 2019

made this a banner . It will appear at the top of every page until it is dismissed by the user. #2

removed this banner . It will no longer appear at the top of every page. #3

pinned globally #4


Reserved. Feedback strongly encouraged.


Thank you Cryptorex for your precisious describtion and your step up for VaultZ activation. I would strongly highlighten the pool Suprnova, because one of the many reason why we constructed a donation method VaultZ was caused by their careless attitude. I dont mean that, everybody should donate but there should be a midpath between huge taxes and lack of donation. VaultZ is our midpath and dont forget we could devote it or modify it by the time passes.

So Suprnova should definitelly update to our new node, and I really hope so they do it.
I would like to add to the exchange list: our members new exchange and his pool which was among our first pools:

Im happily looking forward for the next meetup!
Thank you.


Thank you cryptorex for the new thread for VaultZ.

May I copy here as a reminder what I wrote on Nov 13 2017 on bitcointalk:

Take a developer fee for marketing and infrastructure of 500 BTCZ per block size reward, but do not destroy the factor 1000 in relation to BTC.
The halving will destroy the trust of ‘normal’ people in BTCZ as true BTC 2.0 as explained in post #1 of this thread.
Please could you explain exactly from the advantage site why halving helps?
BTC is mining until year 2040 to get all the 21 mio coins available. Shall BTCZ miners mining until year 2070 to get all available coins?
Halving destroys the reasonable factor 1000 to factor 500, this makes no sense IMHO.
Halving is a contradiction to the basic concept of BTCZ.

Good to see that we add now a small fee for community.



If I understand correctly, the 5% will be taken directly from each new minned block (12500 -5% (665) = 11875 reward block)? And the change will be made in the BTCz Full node (

So the payment gateways ( or and other projects like TxtZ will also have to update the full node.

What will happen for those who do not update? it’s like a hard fork?


I guess, who do not update, will be excluded or can cause huge share errors/ malefuncion at mining (lower rates).
Yes it will be taken from block reward goes to a community or vaultZ address (we will discuss it).
It will be voted what region (eg. Marketing, development…) and what project will get parts for utilites to development (will be discussed).
Receiver should report every transaction or usement of the amount.


Yes - the change will be directly for each new mined block.

Yes - any service running fullnode will need to update. It is effectively a ‘hard fork’, in that those who do not update will be left behind.


We had a discussion on Nov 3rd 2018 to implement VaultZ. Details have been posted/updated on the chart in the original post.

In short we discussed the best approach to upgrading

  1. VaultZ or
  2. VaultZ + Sapling or
  3. VaultZ + Sapling + DynamicZ

As of now - option 1 is the best option as 2 and 3 contain features that are either too ‘new’ or require additional thought.

We’re moving along. :slight_smile:


I think everyone is aware of what is VaultZ,
but it’s not necessarily obvious about Sapling and DynamicZ.

So correct me if I’m wrong …

Sapling is an improvement of the zksnarks protocol,
which makes it possible to perform Z transactions faster and lighter (with less RAM, something like 30 Mb instead of 3 Gb). From this fact, Z transactions can be made from a mobil device.

But, what is DynamicZ (or Stealth-WerkZ)? Strategic partner with SAFEcoin and Safe Trade, auto-trading exchanges of BTCz to fiat (as explained on Project Announcement 06/27)?


Yep - I’d say that’s a well explained description of Sapling.

Regarding DynamicZ - It is a discussion that was introduced by Stealth-WerkZ, but beyond that I cannot say because we believe it is truly innovative. Further evaluation of the idea needs to be tested because it is something I don’t believe we’ve seen. We can’t say much about it yet.


Very nice update! I though we get a live meetup at oct.30th.
Couéd you update exchange list with made by our member PCmining.XYZ?! Pool list also.


Well the oct 30th date was a typo - it was kind of misleading. I meant to type Sept 30th which was the very first dev meeting we had about it.

But yes, a live stream will be in order I’m just waiting for some responses from some components listed and we’ll go live…I kind of miss that!

Thanks! Need to add!


I shared the below on Discord yesterday. I’ve also updated the table in the OP. Choo choo!

We’ve successfully tested VaultZ with a test Community Fee address.

We’ve mined on testnet and the block reward is being split per VaultZ 5% - testing has only used one address but we’re working on how the structure should be - as in there will be over 30 addresses. It seems to be the practice to have many ‘fee’ addresses. The amount of addresses doesn’t change the percentage, they just spread the Community Fee over several addresses.

The test pool where blocks are currently being mined is here:

The testnet explorer successfully shows the block reward seperated out of the 12,500 blockreward - here are details:

Note the 11,875 / 625 BTCZ split (t2CihAq1hbJB49hxWPPifDD7jWRepFoAM2b is a testnet multisig address)

We were successful in spending from the multisig address as well to a shielded address details are here -

I’ll update the forum later, but wanted to share here first. We are still going to do some more testing and figure out the next steps which are getting a codebase for our exchanges and pool configurations, etc. Stay tuned - VaultZ is moving along.


Excelente noticia🤩!!!


Update (and effort!) much appreciated!


Thank you everyone for the support. I’ve updated with a few extra details - nothing in too much detail, but we would like to communicate that our efforts are ongoing.

As you know, the proving method issue announced earlier this year has required us to pivot and update our core node to at least zcash 2.0.3. That many updates requires our test phase to be extended.

We’ve launched a testnet with a lot of changes and are working towards having a production release soon. Please stay tuned. Remember, this is a community effort. Thanks for your patience.


Team renuzit seems to be is making great progress with our major update to zcash core 2.0.3. This will address the proving method ‘vulnerability’, among other upgrades.

The latest progress is blocks are being successfully mined on testnet:

There are a few other things to tidy up, including VaultZ, then we can start scheduling further updates and announcements.

Please stay tuned.