@reckona/mreact-compat

@reckona/mreact-compat implements the React-compatible runtime used by @reckona/mreact, @reckona/mreact-dom, and the compatibility benchmark path. It includes element creation, hooks, context, roots, scheduling, reconciliation, hydration, Suspense, and JSX runtimes.

Basic Usage

Most applications should import from @reckona/mreact instead:

import { createElement, useState } from "@reckona/mreact";

Use @reckona/mreact-compat directly only when testing or integrating the compatibility runtime.

Exports

• @reckona/mreact-compat exposes the core compatibility APIs.
• @reckona/mreact-compat/jsx-runtime and ./jsx-dev-runtime provide JSX runtime entrypoints.
• @reckona/mreact-compat/scheduler exposes the scheduler-compatible API.
• @reckona/mreact-compat/flight and ./internal are framework integration entrypoints.

React 19.2.6 Coverage

The compatibility gate compares the public React, React DOM, React DOM client, and React DOM server export sets against React 19.2.6. New upstream exports must be classified before they can be ignored.

Covered behavior families:

| Area | Coverage | | --- | --- | | Element APIs | createElement, cloneElement, fragments, refs, Children, and JSX runtimes | | Components | Function components, class components, memo, forwardRef, lazy, StrictMode, Activity, and Profiler | | Hooks | State, reducer, context, effects, layout/insertion effects, memo/callback, refs, imperative handles, IDs, transitions, deferred values, external stores, actions, optimistic state, use, and useEffectEvent | | DOM roots | createRoot, hydrateRoot, unmounting, synthetic events, portals, form controls, and hydration mismatch handling | | Server rendering | renderToString, renderToStaticMarkup, renderToReadableStream, renderToPipeableStream, resume, and resumeToPipeableStream | | Resource hints | preconnect, prefetchDNS, preload, preloadModule, preinit, and preinitModule | | Flight | React Flight row parsing, model token decoding, server references, client references, binary chunks, and protocol coverage assertions |

Run the focused compatibility checks with:

pnpm test:react-conformance
pnpm exec vitest run packages/react-compat/test/react-official-conformance.test.ts packages/react-compat/test/react-official-suite-gate.test.ts

Known limits:

• This is a React-like compatibility runtime, not a byte-for-byte React reconciler. The tests assert observable behavior for the supported surface.
• The app-router compiler path is separate from the React-compatible runtime. Compiler and router behavior is covered by their own tests.
• React private internals such as __CLIENT_INTERNALS_DO_NOT_USE_OR_WARN_USERS_THEY_CANNOT_UPGRADE are intentionally classified as private, not implemented as public API.

Notes

The compatibility runtime is useful for drop-in React-like behavior. The faster compiled app path is owned by the compiler, router, server, and reactive DOM packages.