What problem does it solve? Convex validates every existing document against a new schema and fails the push if any row does not conform, so pushing an untested schema change directly to production risks a rejected deploy or broken data. This Skill turns a preview deployment into a rehearsal copy seeded with a production snapshot, letting the conformance gate fail safely on the copy before the proven change is promoted to prod. ## Core Features & Use Cases - Snapshot-seeded preview rehearsal: Export production data with npx convex export, create a preview deployment from pre-change code, and import the snapshot so the schema gate fails on the copy instead of prod. - Ordered migration workflow: Follows the optional-field-first pattern (make field optional, push, backfill with @convex-dev/migrations, verify, tighten validator, push again) on the preview before repeating the proven sequence on production. - Guarded promotion with rollback: Requires a fresh explicit confirmation before the prod promote and keeps the snapshot as a rollback artifact via npx convex import --replace --prod. - Use Case: You need to add a required role field to a Convex users table with millions of rows. Rehearse the schema change and batched backfill on a snapshot-seeded preview, verify the app against migrated data, then promote the exact proven sequence to production. ## Quick Start Rehearse my Convex schema change and backfill on a snapshot-seeded preview deployment, verify it, then promote the proven change to production with the snapshot kept as rollback.
