Budapest, Hungary, August 21st, 2023.

Tired of waiting for transaction confirmations? So are we! Much time has been spent trying to solve this ubiquitous issue. As a result, we’ve packed Wasabi Wallet version 2.0.4 with highly requested features and a bundle of performance optimizations that drastically speeds up wallet load time, frees transactions from getting stuck in the mempool and make life easier than ever for privacy-conscious Bitcoiners. 

Key upgrades include transaction speedup with RBF and CPFP, privacy warnings when sending transactions, and a headless daemon for advanced users who prefer using their keyboard instead of their mouse. Tasks running in the background now take even less time with improvements made to coinjoin output efficiency and wallet synchronization speed.

Since the last release four months ago, the amount of progress is mind-blowing. Now Wasabi is even faster, more private, and easier to use. The contributors have really outdone themselves this time.” ~ Max Hillebrand, CEO at zkSNACKs and Contributor to Wasabi Wallet 

Don’t Float in the Mempool

Unpredictable gaps of time between blocks often lead to users overpaying on fees for urgent transactions to avoid getting stuck in the mempool below competing bids. Wasabi’s new transaction speedup feature eliminates this risky gamble so users always win. Incoming funds can now be secured quickly with Child Pays For Parent (CPFP) to self-spend an unconfirmed UTXO, and outgoing transactions can use Replace By Fee (RBF) to increase confirmation priority or cancel the payment entirely. In addition to these flexible new features, clients now adapt to high mempool fees and never create small value coinjoin outputs that would be uneconomical to spend. Coinjoin reliability was reinforced further on the coordinator side with more accurate fee rate measurements and a robust transaction broadcasting process.

Turbosync Drastically Reduces Wallet Load Times

Wasabi clients use compact block filters to privately synchronize a wallet’s balance with the Bitcoin network. Block filters allow light clients to download only the blocks that contain their transactions instead of downloading every block like a fully validating node. This release optimizes the filter-checking process to reduce wallet loading times by 90% thanks to code cleanup and a clever key prioritization process dubbed “Turbosync”. With Turbosync, internal addresses that have already been used are not checked for coins in new blocks until after unused addresses have been checked first. Filter performance improved even more by storing them in an SQLite database instead of a plaintext file, reducing disk space requirements by about 1 GB and increasing resilience against file corruption.

Privacy Warnings and Spending Suggestions

New Privacy Warnings present users with one-click fixes if they are attempting to construct a transaction that spends nonprivate funds or creates change. Notifications are provided when consolidating more than 10 UTXOs or spending unconfirmed funds, allowing users to avoid potential mistakes without restricting intentional usage.

More Privacy, Less Blockspace

The amount decomposer was refined to make the most effective use of scarce block space so that whales who set a high anonymity score target now need fewer coinjoin rounds to reach 100% privacy. The amount of outputs a client can create in a round has been increased from 8 to 10, and decompositions that produce change outputs are now rarely chosen. The occurrence of non-private coinjoin “toxic” outputs is reduced even further to improve coinjoin efficiency. Adjustments to the anonymity score calculator and default settings additionally reduce the amount of coinjoining required before all coins are considered private. The anonymity score target of the “Maximize Privacy” coinjoin strategy setting was reduced from a random value between 50-100 to a less conservative range of 27-76, which brings the behavior closer in line with the two efficiency-based strategies.

Headless Daemon

More experienced users can directly interact with the core features of the wallet through an RPC (Remote Procedure Call) interface making it easy for developers to customize their experience and build features that are not available in the GUI version. This release bundles the Daemon, an executable called ‘wassabeed’ that runs the wallet without the graphical interface. The wallet can be run in the background by using the RPC interface allowing users to coinjoin, see their balance, and perform every other function of the wallet without the resource consumption of the graphical interface.

Other Features

  • QR code scanning for Linux to copy payment addresses
  • Improved Tor behavior
  • Hardware Wallet Interface updated to v2.2.1
  • Decoupling of the user interface for better testing and alternate client support
  • Separation of WabiSabi cryptography library for compatibility with other projects
  • Sunset of Wasabi Wallet 1.0 zerolink coinjoin coordination

About Wasabi Wallet

Reclaim your privacy with Wasabi Wallet, a free and open-source bitcoin wallet with built-in coinjoins. Coinjoins are collaborative bitcoin transactions that enable cash-like privacy features for bitcoin.

Download Wasabi Wallet here .