Using the attached snapcraft.yaml, snap builds with conflicting libs: $ find /snap/duplicity/current/ -type d -name 'python3*' <snip> /snap/duplicity/current/usr/lib/python3 /snap/duplicity/current/usr/lib/python3.8 <-- this should be here **** /snap/duplicity/current/usr/lib/python3.9 <-- this one causes confusion **** <snip> Since duplicity uses _librsync*.so and that's only installed in python3.8, it fails when python 3.9 is used, as is done on Debian 10. It's only one executable and should only have one version of python supplied in the snap.