FEATURE: Stream stdout when running commands #35
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Previously the stdout of commands was buffered in memory, and then logged when it was finished. Meanwhile, the stderr of a command was being streamed straight out. This leads to some very surprising output when commands mix stdout & stderr (e.g. rails database migration errors). Now, stdout and stderr are passed straight through, so long-running command output appears in real-time, and correctly ordered. For the simple case, a `system()` call would work. But we need to handle the `stdin` option, which is why we need the extra complexity and `Process.spawn`.
SamSaffron
approved these changes
Jan 7, 2026
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Previously the stdout of commands was buffered in memory, and then logged when it was finished. Meanwhile, the stderr of a command was being streamed straight out. This leads to some very surprising output when commands mix stdout & stderr (e.g. rails database migration errors).
Now, stdout and stderr are passed straight through, so long-running command output appears in real-time, and correctly ordered.
For the simple case, a
system()call would work. But we need to handle thestdinoption, which is why we need the extra complexity andProcess.spawn.