@melon-db/db-codemods

WatermelonDB → Melon codemods and runtime query translator.

Docs: /docs/packages/melon-db-codemods · Migration guide

CLI

bun run melon-codemod migrate-queries --path=./src
bun run melon-codemod migrate-writes --path=./src
bun run melon-codemod migrate-react --path=./src
bun run melon-codemod migrate-schema --path=./src/models/Task.ts

Add --dry-run to preview without writing files. migrate-schema prints JSON to stdout (read-only).

Compatibility matrix (v2)

| WatermelonDB | Melon codemod | Notes | |--------------|---------------|-------| | database.get('x').query(Q.*) | db.collection('x').findMany(q.from(...)) | Shipped | | Q.and / Q.or | .and(q2 => …) / .or(q2 => …) | Shipped (Phase 19) | | .query(...).fetch() / .observe() | .query(q.from(...).toAst()).fetch() | Shipped (Phase 19) | | Q.on (joins) | relationFilters when schema passed to translator | Codemod recipe if schema unknown | | database.write + create/update | db.write(tx => …) | Shipped | | record.destroyPermanently | tx.collection(...).delete(id) | Shipped (Phase 19) | | database.batch inside write | tx.batch(...) | Partial — verify ops | | DatabaseProvider | MelonDbProvider | Shipped | | withObservables | Hook migration comment | Shipped (Phase 19) | | @field Model class | migrate-schema JSON spike | Single-file extraction |

Runtime translateWatermelonQuery(collection, clauses, schema?) converts serializable Q clauses to QueryAst. Pass MelonSchema to compile Q.on into relationFilters (belongsTo only). Experimental Watermelon join tables are unsupported.

Author & license

Copyright (c) 2026 Nate Nichols. See LICENSE for the full MIT license text.