Haven 3.0 Development progress

Last updated: 01 December 2022


  • VBS core functionality
  • Specific offshore
  • Specific onshore
  • Max offshore
  • Implement cryptographic verification for offshore and onshore collateral
  • Design work on implementation of block cap
  • Fix for split TXs (conversion TXs are now blocked from being split, because it breaks VBS)
  • xAssets conversion fees
  • Offshore change to 1.5%
  • Onshore change to 1.5%
  • Fixes to support dynamic TX fee & block size scaling
    26 October 2022
  • Merge offshore fee functions (wallet2 + cryptonote_tx_utils)
  • Fix for TX sorting / selection algorithm (to improve efficiency in line with block cap implementation)
    This fix improves the efficiency of the TX selection to maximise capacity in the blocks, which also increases revenue for miners.
  • Max onshore
    28 October 2022
  • TX structure optimizations – remove masks sums from TX if it isn’t conversion TX
    02 November 2022
  • TX structure optimizations – mark collateral outputs on TX and validate collateral unlock times
  • Fix xAssets conversion fees
  • Fix error on low value TX fees
    04 November 2022
  • Block cap implementation
  • Update wallet-rpc methods
    11 November 2022
  • General review (formulas, implementaion & bugs etc..) before internal testnet
    18 November 2022
  • Internal Testnet

In progress

  • Public Stagenet
  • Miners & Pools notification
  • Public Testnet
  • Audit by Cypher Stack
  • Wallet GUI development
  • Audit the new collateral verification code (no time estimate – will go parallel with outstanding tasks)
    – Security review
    – Privacy review

Estimate time line for the above “In progress” list is 1 to 2 weeks.


  • Notify exchanges of the fork

Notes on Block Cap

As suggested by some community members, the block cap formula initially proposed was not a direct function of the XHV supply, as well as being too large with increasing market cap.

As part of the TX sorting fix being implemented, the block cap formula has been updated in order to provide a higher level of protection against inflation, as well as disincentivizing large transactions being split, which would increase the TX pool.

The table below shows the new formula for the block cap and how it affects the block level for different XHV supplies, price and market cap.

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