To enable public signups on Astronomer, add
publicSignups: true as a top-level field in your Helm config:
astronomer: houston: config: publicSignups: true email: enabled: true smtpUrl: smtp://<user>:<pw>@ses-smtp-astro.20190812-200513/?requireTLS=true
If you’d like your users to be able to receive email invites to the cluster, make sure to keep the email portion of the config. Otherwise, anyone can just sign up at your domain and view workspaces they have access to independent of invitations.