convex-migration-helper

A zero-downtime Convex schema migration uses a widen-migrate-narrow workflow and the @convex-dev/migrations component to widen the schema, batch backfill data, then safely narrow the schema to minimize risk.

The safest way to handle breaking schema changes in Convex is the widen-narrow workflow, which supports adding, removing, or renaming fields and splitting tables while ensuring safe data handling and rollback readiness.

Yes, you can use the @convex-dev/migrations component to backfill data across deployments. It provides batched, resumable migrations that ensure safe data handling during the backfill process across different environments.

To plan a data migration without production downtime, apply an online migration model that widens the schema first, migrates data in resumable batches, and enforces rollback readiness before narrowing the schema.

The widen-migrate-narrow workflow requires enforcing the online migration model and safe data handling. It is limited by the need for batched, resumable migrations to avoid downtime and ensure rollback readiness during schema narrowing.