QEMU 8.x crashes running x86_64 programs on an arm64 host (QEMU issue 2168), which the 8.1.5 pin walked into, and 10.2 segfaults on the runner as well; 9.2.2 runs node, composer and install-php-extensions on the runner's host. The Composer and npm stages now build on the build machine's platform: their output is the same for every target, so a multi-arch build runs them once and natively. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01V9NnLxnPp8vaaurb3Z1MFy