alembic.ini is a Flask-Migrate config with no script_location, so ScriptDirectory.from_config raised and _current_schema_revisions swallowed it and returned no heads. Every set then failed the subset check and was wrongly blocked as taken on a newer schema than the running code. Set script_location to the migrations directory - the same versions tree the manifest scans - so live heads resolve and compatible sets restore.
Backups are per-site and not part of the base stack, so they ship as a separate compose overlay with an isolated restic REST server the app can only reach through the backup utility (no shell or db creds). The sidecar image trusts the corporate proxy root CA at build time so its Oracle yum, github, and PyPI fetches succeed behind TLS interception; shell scripts are pinned to LF via .gitattributes so the container entrypoints do not die on a CRLF shebang.
