Convex Migrate Rehearse

Rehearse a risky Convex schema change before it touches prod. You seed a preview deployment with a prod snapshot, push the schema and run the backfill there, and let Convex's conformance check fail on the copy instead of on your live data. Once it's green, the same optional-then-backfill-then-tighten sequence goes to prod, with the snapshot kept as your rollback. It's worth reaching for whenever a schema change will tighten a validator over existing rows. The honest catch: it needs a Preview Deploy Key, which is a paid-tier feature, and a snapshot restore loses anything written after the export, so keep the promote window short. The fallback to a personal dev deployment works, but you lose the isolation that makes it trustworthy.

skills.sh installs: 41.1K
GitHub stars: 69
last updated: Oct 26, 2026

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Install

$ npx -y skills add convex/agent-skills --skill convex-migrate-rehearse --agent claude-code

Installs into .claude/skills of the current project.

Files

Rehearse a schema change on a preview before prod

A schema push on Convex validates every existing document against the new schema and FAILS the push if any row doesn't conform — a real data-conformance gate. The safe way to use that gate is to let it fail on a rehearsal copy, not on prod. This capability turns a preview deployment into that copy: seed it with a prod snapshot, push the new schema + run the backfill there, watch the gate, and only promote once it's green. It composes deploy-guard (target classification), migrate (the optional-then-tighten pattern), and @convex-dev/migrations (the batched, resumable backfill).