Hi
The build is happening on snapcraft - the install and run is happening on Raspberry Pi3 with raspios.
sudo snap list
Name Version Rev Tracking Publisher Notes
core 16-2.48.2.1 10827 latest/stable canonical✓ core
core18 20210128 1989 latest/stable canonical✓ base
node-red 1.2.9 686 latest/edge noderedteam✓ -
snapd 2.48.2.1 11042 latest/stable canonical✓ snapd