What problem does it solve? Changing the schema of a live Convex app risks breaking existing data: tightening a validator before old rows are updated causes deploys to reject them and breaks the production app. This Skill provides a safe, ordered workflow for evolving schemas without downtime. ## Core Features & Use Cases - Staged Schema Changes: Add new fields as optional first so deploys never reject existing rows. - Guided Backfills: Install @convex-dev/migrations and write migrations that transform or backfill existing rows. - Verification Before Tightening: Verify row counts and validity before making a field required. - Use Case: You need to add a required role field to a users table in production. Follow the workflow to add it as optional, backfill all existing users, verify the counts, then tighten the validator. ## Quick Start Help me add a required field to my live Convex app's schema and backfill the existing rows safely.