Function start_failed 

fn start_failed(program: &str, e: &Error) -> String

What to say about a child that never started.

NotFound is not an unusual system here, it is the shipped one: the image is distroless, so it has no bash, no curl and no writable install directory, and the raw “No such file or directory (os error 2)” names the symptom while hiding the answer — a container upgrades by pulling a newer tag, not by rewriting its own rootfs. Every other tool the installer needs already refuses by name (curl-or-wget in command, sha256sum in the script), so this is the last case that did not.