Declarative Schemas 2.0 with pg-delta

On October 2 at Supabase Select we shipped Declarative Schemas 2.0. The Supabase CLI now generates migrations with pg-delta, a Postgres diff tool we wrote and open sourced, in place of migra, the technology behind our original implementation. Generated migrations now include RLS policy changes, grants, view settings, partitions, domains, and objects that extensions manage. Declarative schemas first launched in April 2025. You keep your schema in SQL files under supabase/schemas/, edit them, and the CLI writes the migration. In 2.0 that workflow is the same: edit a file, generate the migration, review it, and apply it. New CLI projects get 2.0 by default. Existing projects opt in with one config block. In this post we cover why we built pg-delta, how to turn it on, a working example, and what it does not do yet. migra is an open source Python tool that diffs two Postgres databases and emits the SQL between them. It has powered supabase db diff since the first CLI prototype in 2021. migra didn't understand domains, publications, or comments. Changes to them never appeared in the diff. You read every generated migration line by line to find what was missing. The limitations list in our…