MobX 7.0.0

Major Changes

• 1926c69f53168619d688f348aa587e8f3ae579ae #4671 Thanks @kubk! - Release MobX 7, mobx-react-lite 5, and mobx-react 10.

  Bundle sizes are down: ESM prod 17.02 KiB gzip -> 13.96 KiB gzip; a minimal tree-shaken example is 10.32 KiB gzip now.

  It removes long-deprecated compatibility paths and keeps the React bindings split between mobx-react-lite for function components and mobx-react for class-component support.

  MobX 7

  MobX 7 is a cleanup release focused on the modern runtime and decorator model.

  • MobX now always uses Proxy-backed observable objects and arrays. The ES5/non-proxy fallback has been removed.
  • configure({ useProxies: ... }) is no longer supported.
  • { proxy: false } options for observable, observable.object, and observable.array are no longer supported.
  • Legacy decorators are no longer supported.
  • Namespaced annotation and comparer properties now use named exports to reduce bundle size:

  Removed API	Replacement
  observable.ref	observableRef
  observable.shallow	observableShallow
  observable.deep	observableDeep
  observable.struct	observableStruct
  computed.struct	computedStruct
  action.bound	actionBound
  flow.bound	flowBound
  comparer.identity	compareIdentity
  comparer.default	compareDefault
  comparer.structural	compareStructural
  comparer.shallow	compareShallow

  • The public trace API and its related runtime support have been removed. Use toJS, getDependencyTree, getObserverTree, spy or mobx-log package for debugging.

  mobx-react-lite 5 and mobx-react 10

  mobx-react-lite 5 and mobx-react 10 require MobX 7 and React 18 or later.

  mobx-react-lite remains the function-component package. mobx-react remains a thin wrapper around mobx-react-lite that adds class component and Stage 3 @observer class decorator support.

  • Keep function-component imports on mobx-react-lite if you do not need class component support.
  • Use mobx-react when you need class components or @observer class decorators.
  • mobx-react-lite supports function components and forwardRef; mobx-react delegates function components to mobx-react-lite and handles classes itself.
  • Remove React batching imports, including the stale React Native batching deep import. React 18+ renderers handle batching.

  The recommended public React binding surface for both packages is:

  • observer
  • Observer
  • useLocalObservable
  • enableStaticRendering
  • isUsingStaticRendering

  The following APIs have been removed from the React binding packages:

  • Provider, inject, and MobXProviderContext; use React.createContext directly.
  • disposeOnUnmount; dispose reactions in componentWillUnmount or return cleanup functions from useEffect.
  • PropTypes; use TypeScript or the regular prop-types package.
  • useObserver; wrap components with observer or use <Observer>.
  • useLocalStore; use useLocalObservable.
  • useAsObservableSource; synchronize values from props into local observable state explicitly.
  • useStaticRendering; use enableStaticRendering.
  • observerBatching, isObserverBatched, batchingForReactDom, batchingOptOut, and batchingForReactNative; remove these imports because React 18+ renderers handle batching.
  • Deprecated observer(fn, { forwardRef: true }); pass an already-created React.forwardRef(...) component to observer instead.
  • Legacy function-component contextTypes handling.

Patch Changes

• 979d267d569734dc3cb969ed1880ed68bb79f1b5 #4677 Thanks @kubk! - Shorten minified error URL to reduce production bundle size.