no admin user on new version (1.15.3)

I'm trying a local install of gancio for testing of the newest version. The install process is smooth, and at the end I log in with the given admin + password provided by the web set-up "wizard", but the admin user does not appear to actually be an administrator! There's no access to the admin panel, just the Options available to an ordinary user.

I confirmed this using the CLI:

$ gancio users list
1 role: user enabled: true email: admin

Further, I've tried promoting the admin user to an administrator using the CLI which fails and deleting the admin user and recreating it, or otherwise creating a new user with the --admin flag:

$ gancio users create test@example.com --admin
User "test@exmaple.com" created with role user

I tried installing with the new "Enable moderation" slider selected, and again without. Same result. Maybe I am missing something obvious, or there is a bug otherwise worth getting to the bottom of it. Any ideas?