Major Bitcoin Core update changes default wallet protocols, risking temporary disruption across popular apps

Bitcoin Core tagged v32.0rc1 on Sept. 14 with a GPG-verified signature, setting an aim for the final v32.0 release on Oct. 10. The release schedule issue #35122 confirms the timeline, leaving a 26-day window for node operators, wallet providers, and services to test the candidate against the 31.1 baseline.

The draft release notes identify four RPCs that will default to PSBTv2 in v32.0. According to the article, this change requires compatibility checks across wallet parsers and signers. Teams that create, convert, or fee-bump PSBTs must trace those transactions through downstream parsers to ensure they handle the new version correctly. Other interfaces will remove deprecated fields or reject arguments that older versions tolerated, broadening the test surface beyond just the PSBTs.

Eight workers handle the parallel prefetching of transaction outputs during block connection, with support for a maximum of 16, a change intended to speed up block processing. The article notes that running disk-bound validation with multiple settings can reveal whether this faster processing comes with unacceptable CPU, memory, or storage-latency costs on specific hardware.

A new 8,192-byte header limit is now enforced by the rewritten HTTP server, alongside a standard cap of 16 RPC connections. These changes can surface in reverse proxies, health checks, and client pools. Disk usage for the restructured transaction index drops by over fifty percent; however, legacy versions fail to parse the updated structure, meaning a downgrade can trigger another rebuild lasting hours. Privacy-focused operators should reproduce private-broadcast failure paths around the Tor fallback fix, which involves a 10,000-entry queue and a 1,000-attempt limit.