Reflex exported frontend compatibility after backend version rollback

The goal is to determine whether a Reflex exported frontend artifact can be safely restored or rebuilt when the associated Python backend has been rolled back after a failed upgrade, preserving functional consistency without unintended state divergence.

Key constraints include the version coupling between the compiled frontend bundle and the backend API surface, the persistence of dependency manifests such as package.json or reflex.toml, and the separation of database schema changes from code rollback, which may remain applied even when both code and frontend are reverted.

Uncertainty surrounds the trade-off between rebuilding from restored source files, which aligns with the original build context, and restoring a prior exported bundle, which prioritizes speed but risks incompatibility if the frontend was generated by a newer Reflex release than the rolled-back backend.

Under what conditions does a restored frontend export maintain API compatibility with a rolled-back backend? What minimal set of version markers and manifest artifacts is required to validate a consistent recovery? Can database schema changes be independently reversed without affecting frontend-backend runtime parity?