uppy/MIGRATION-6.0-merge-into-core.md

Migration: packages merged into @uppy/core (6.0)

In Uppy 6.0, four packages were folded into @uppy/core and are now exposed through subpath exports. The standalone packages are removed from npm. This eliminates a class of duplicate-version bugs (every plugin already depends on @uppy/core, so there is now a single source of truth) and lets co-dependent types reference each other directly instead of through hand-maintained duplicates.

1. Import paths

Update imports from the removed packages to the matching @uppy/core subpath:

Removed package	New import
@uppy/utils	@uppy/core/utils
@uppy/store-default	@uppy/core/store-default
@uppy/companion-client	@uppy/core/companion-client
@uppy/provider-views	@uppy/core/provider-views

- import { fetcher } from '@uppy/utils'
+ import { fetcher } from '@uppy/core/utils'

- import { RequestClient } from '@uppy/companion-client'
+ import { RequestClient } from '@uppy/core/companion-client'

Then:

1. Remove @uppy/utils, @uppy/store-default, @uppy/companion-client, and @uppy/provider-views from your package.json.
2. Make sure @uppy/core is listed as a dependency (it already is for any plugin).

2. CSS

The provider UI styles moved with the code:

Old	New
@uppy/provider-views/css/style.min.css	@uppy/core/provider-views/css/style.min.css
@uppy/provider-views/css/style.css	@uppy/core/provider-views/css/style.css

Most apps don't import this directly — it ships bundled in @uppy/dashboard's CSS. Only update it if you were importing the provider-views stylesheet explicitly.

3. TypeScript types

• RequestOptions moved from @uppy/utils to @uppy/core/companion-client (it is the companion request type and now lives next to RequestClient).

  - import type { RequestOptions } from '@uppy/utils'
  + import type { RequestOptions } from '@uppy/core/companion-client'
  

• CompanionClientProvider / CompanionClientSearchProvider are removed. They were hand-maintained stand-ins that only existed because @uppy/utils couldn't see the real provider classes. Now that everything lives in @uppy/core, the real classes are used directly. If you typed against them, import the real class from @uppy/core/companion-client instead (or Pick the members you need):

  - import type { CompanionClientProvider } from '@uppy/utils'
  + import type Provider from '@uppy/core/companion-client'
  - const p: CompanionClientProvider = ...
  + const p: Provider<MyMeta, MyBody> = ...
  

  Note: UnknownProviderPlugin['provider'] is now typed as a structural subset of Provider (via Pick), so a custom provider that matches the public surface still fits without subclassing the exact class.

4. The uppy all-in-one package — no change

If you use the meta-package or the CDN bundle, nothing changes:

import { Uppy, Dashboard, DefaultStore } from 'uppy' // still works
// window.Uppy.DefaultStore — still works

These re-exports were repointed to the new @uppy/core subpaths internally.