TL;DR

MobX now correctly resolves the bundled jscodeshift (code transformation tool) binary when used with npm workspaces, ensuring the CLI functions as expected in complex projects.

Fixes Worth Knowing

The MobX CLI now correctly locates its dependencies when used in npm workspaces, resolving issues with code transformations.

TL;DR

MobX now initializes computed properties and observables lazily (on first access) which significantly reduces memory usage and startup time for applications with many observable properties.

New

• Computed properties are now created only when first read, avoiding unnecessary allocations.
• Observable properties are now created only when first read/written to, improving performance with sparse data.

Fixes Worth Knowing

• A regression introduced in a previous release, where isComputedProp incorrectly returned false for lazy computed properties, has been resolved.
• ObservableMap now includes getOrInsert and getOrInsertComputed methods for compatibility with newer Map typings (JavaScript data structure).

TL;DR

MobX React now avoids warnings when used with Babel (a JavaScript compiler), improving the developer experience.

Fixes Worth Knowing

Resolved an issue causing unnecessary warnings with Babel-compiled React code. This improves the development workflow by reducing console noise.

TL;DR

MobX React Lite now supports React 19, ensuring compatibility with the latest version of the popular UI library (JavaScript framework).

New

• Added support for React 19.

TL;DR

This release updates the MobX ESLint plugin to support ESLint 9 and its new flat config (configuration files), improving compatibility and developer experience.

New

• Added support for ESLint 9.
• Implemented a flat config option for streamlined configuration.

Fixes Worth Knowing

• Corrected the configuration name for the recommended flat config.

TL;DR

MobX React Lite now correctly handles FinalizationRegistry (garbage collection) and timer clearing, resolving potential memory leaks and ensuring reliable cleanup of reactive components.

Fixes Worth Knowing

Resolved a regression that caused incorrect timer clearing, which could lead to unexpected behavior in reactive components. Improved support for FinalizationRegistry, preventing potential memory leaks when observables are garbage collected.

TL;DR

MobX-React now fully supports TypeScript 4.8 and later, ensuring compatibility for developers using the newest TypeScript features.

New

• TypeScript 4.8 compatibility: Enables use with the latest TypeScript version.

TL;DR

Check NPM for the latest MobX release (a state management library) as GitHub releases are not used for this project.

Before You Upgrade

Visit npmjs.com/package/mobx to find and install the newest version.

TL;DR

MobX now supports iteration over ObservableMap and ObservableArray objects, enabling easier data processing with modern JavaScript tools.

New

• ObservableMap and ObservableArray support iterators (standard data structures for looping).

Fixes Worth Knowing

• Resolved an issue where ObservableMap failed to initialize with empty values in Safari.