ogra@anubis:~/datengrab/snaps/snap-inspector-term$ cat meta/package.yaml 
name: snap-inspector-term
vendor: Oliver Grawert <ogra@ubuntu.com>
architecture: [amd64, armhf]
icon: meta/icon.svg
version: 0.1-1
services:
 - name: snap-inspector-term
   description: "Inspect the environment of a snap package in a browser"
   start: start-service.sh
   ports:
     external:
       ui:
         port: 8090/tcp
         negotiable: no
ogra@anubis:~/datengrab/snaps/snap-inspector-term$ snappy build .
Warnings
--------
 - snappy-systemd_hook_unknown_key_snap-inspector-term.snappy-systemd
	Unknown field 'ports'
 - snappy-systemd_package_yaml_unknown_key_snap-inspector-term.snappy-systemd
	Unknown field 'ports'
snap-inspector-term_0.1-1_multi.snap: FAIL
Generated 'snap-inspector-term_0.1-1_multi.snap' snap