The aarch64 job targets the spark-1 self-hosted runner, whose labels are registered as 'Linux' not 'linux'. Cargo.lock is committed because the Dockerfile builds with --locked and a lockfile-free reproducible build is not reproducible. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01JkyvfNJGTshJNE9FtwPLk7