I'm trying to snap rainbowstream [1]. It uses the python plugin and requires libc6-dev as a stage package, but that fails to snap with this error: [Errno 1] Operation not permitted: '/tmp/test/parts/my-part/install/usr/lib/x86_64-linux-gnu/libutil.so' To reproduce: $ snapcraft init edit the snapcraft.yaml: change the plugin to python, and add stage-packages: [libc6-dev] $ snapcraft [1] https://github.com/elopio/rainbowstream/tree/snapcraft