# Backfill application package files for custom and standard apps
- Backfill `package.json` / `yarn.lock` (and related fields) for
existing workspaces; new standard/custom apps get default dependency
files.
- Default package files under
`application/constants/default-package-files/`; util with hardcoded
checksums (comment on how to regenerate).
- New **FileFolder.Dependencies** for app dependency files;
**writeFile_v2** accepts optional `queryRunner` for transactional
writes.
Usages:
- **Upgrade command** `upgrade:1-17:backfill-application-package-files`:
standard/custom apps → default files; other apps → from logic function
layer.
- **Workspace creation**: create workspace with
`workspaceCustomApplicationId` first, then create application (enables
same-transaction insert). Migration makes workspace/application/file FKs
deferrable.
- dev seeder
