Bitcoin ABC 0.33.0 Release Notes

Bitcoin ABC version 0.33.0 is now available from:

https://download.bitcoinabc.org/0.33.0/

This release includes the following features and fixes:

• If -proxy= is given together with -noonion then the provided proxy will not be set as a proxy for reaching the Tor network. So it will not be possible to open manual connections to the Tor network for example with the addnode RPC. To mimic the old behavior use -proxy= together with -onlynet= listing all relevant networks except onion.
• With I2P connections, a new, transient address is used for each outbound connection if -i2pacceptincoming=0.
• Ports specified in -port and -rpcport options are now validated at startup. Values that previously worked and were considered valid can now result in errors.
• UNIX domain sockets can now be used for proxy connections. Set -onion or -proxy to the local socket path with the prefix unix: (e.g. -onion=unix:/home/me/torsocket).
• Passing an invalid -rpcauth argument now cause bitcoind to fail to start.
• The thoughput of Avalanche Pre-Consensus has been increased by voting on more items in a single message. A new option -avamaxelementpoll allows the node operator to further tune this value if desired.
• The default block size for mining has been increased to 16MB. The previous default value was very conservative and this is no longer relevant since Avalanche Pre-Consensus made block generation much faster. The value can still be tuned with the -blockmaxsize if desired.

At the MTP time of 1778846400 (May 15, 2026 12:00:00 UTC), the following changes will be activated:

• Bump automatic replay protection to the next upgrade, timestamp 1794744000 (November 15, 2026 12:00:00 UTC).