Logging (Bitcoin Core Dev Tech, May 2026)

A discussion of whether Bitcoin Core has a coherent vision for logging, centered on structured logging (PR #34374). The kernel C API currently logs plain strings, forcing every consumer to implement its own parsing; a struct-based, JSON-parseable approach is preferred and was described as uncontroversial.

The conversation covered why the kernel needs any log filtering (for in-code efficiency, with the atomics and bit-setting living in a utility log module), context-aware logging (favoring a function that takes the wallet as a parameter over a custom wallet-aware logger), automatic source-location logging, and consolidating the related PRs for review. A guiding note: if the kernel does not itself rely on logging, it should not drive the logging design.