Warning: do not use no english names in paths!
Local building for x86-64 (Host: Ubuntu 20.04 64 bit):
sudo snap install snapcraft --classic
snapcraft
Local building for arm64 (Host: Ubuntu 20.04 server 64 bit - https://ubuntu.com/download/raspberry-pi)
sudo snap install snapcraft
SNAPCRAFT_BUILD_ENVIRONMENT=host snapcraft
Install local build:
sudo snap install ponysay_3.0.3_amd64.snap --dangerous
Publishing:
snapcraft login
snapcraft push --release=stable ponysay_3.0.3_amd64.snap