Use it now Notable
A new env var stops Claude Code from hanging when stdout is slow, like when piped somewhere.
A new CLAUDE_CODE_NONBLOCKING_STDOUT environment variable makes the terminal renderer install a non-blocking stdout writer with backpressure handling instead of writing directly. This can prevent the process from hanging when stdout is slow or blocked, such as when piped to a slow consumer.
Names in the bundleCLAUDE_CODE_NONBLOCKING_STDOUT
Documented inclaude-code/env-vars
One source agreesOne thing we can check says the same as this entry.
The name it cites is new in this build
New in this build: CLAUDE_CODE_NONBLOCKING_STDOUT