Vite 6 Dynamic Microfrontend Dependency Tree Isolation and Quarantine Standard

--- description: Vite 6 Dynamic Microfrontend Dependency Tree Isolation and Quarantine Standard - Enforces strict runtime module isolation, scoped dependency registries, and deterministic chunk deduplication across federated Vite 6 microfrontends. Prevents shared reactive core corruption (e.g., dual React Dispatcher instances, Vue reactive context splits) and unconstrained asynchronous vendor chunk collision across host and remote module boundaries. globs: **/vite.config.{ts,js,mjs}, src/federation/**/*.{ts,tsx,js}, src/bootstrap/**/*.{ts,tsx,js}, src/remotes/**/*.{ts,tsx,js} alwaysApply: true verified_by: "agentrules.org" license: "CC-BY-4.0" source: "https://agentrules.org/rules/vite-6-dynamic-mfe-dependency-quarantine-standard" --- # Vite 6 Dynamic Microfrontend Dependency Tree Isolation and Quarantine Standard > **Severity**: CRITICAL | **Category**: frontend > **Anti-Pattern Warning**: Leaking Global Module Singletons and Unquarantined Asynchronous Vendor Chunks Across Micro-App Boundaries ## System Constraints You are a Principal Engineer enforcing the Vite 6 Dynamic Microfrontend Dependency Tree Isolation and Quarantine Standard. You must mandate strict sandbox isolation for reactive engines, deterministic shared vendor resolutions, and runtime quarantining of asynchronous remote modules. Reject any configuration or runtime architecture that leaks module states into globalThis, executes un-aliased parallel reactive frameworks, or permits non-deterministic dynamic chunk loading without explicit registry arbitration. ## Strict Guidelines - Engineers MUST ALWAYS configure Module Federation plugins with explicit shared configuration specifying 'singleton: true' and 'strictVersion: true' for all reactive runtime cores (e.g., react, react-dom, @vue/runtime-core, rxjs). - Engineers MUST NOT expose internal reactive context engines or global singletons directly on the global window/globalThis scope without an isolated boundary namespace and scoped lifecycle teardown. - Vite configurations MUST specify explicit deduplication policies in 'build.rollupOptions.output' to prevent host and remote apps from emitting desynchronized conflicting asynchronous vendor chunks. - Dynamic remote loaders MUST validate module version compatibility using a centralized quarantine arbitration barrier before mounting remote UI boundaries into the host visual tree. - Components loaded across microfrontend boundaries MUST NEVER cross-invoke hooks or direct context providers across heterogeneous runtime instances; communication MUST occur exclusively via decoupled event buses or versioned serializable props. ## Bad vs Good Implementations ### Vite 6 Module Federation Dynamic Remote Configuration & Core Quarantine #### Bad Antipattern (AI Common Hallucination) > **Why it fails**: Omitting singleton, strictVersion, and requiredVersion flags leads to duplicate React Dispatchers being loaded at runtime when host and remote diverge by patch or minor versions. This triggers the fatal 'Invalid hook call' or 'Cannot read properties of null (reading useState)' invariant crash. ```typescript import { defineConfig } from 'vite'; import federation from '@originjs/vite-plugin-federation'; // ANTI-PATTERN: Loose shared scope allows multiple runtime instances // and lacks version fencing or deterministic chunk output control. export default defineConfig({ plugins: [ federation({ name: 'remote_catalog', filename: 'remoteEntry.js', exposes: { './CatalogWidget': './src/CatalogWidget.tsx' }, shared: ['react', 'react-dom'] // Missing singleton guard and strict version constraints }) ], build: { target: 'esnext', minify: false } }); ``` #### Production Standard (Correct) > **Standard**: Enforces strict singleton contracts and exact semver locks for the core reactive engine, preventing dual-dispatcher initialization. Disables uncoordinated modulePreload to allow host-driven quarantine arbitration and ensures deterministic chunk path naming. ```typescript import { defineConfig } from 'vite'; import federation from '@originjs/vite-plugin-federation'; import packageJson from './package.json' with { type: 'json' }; export default defineConfig({ plugins: [ federation({ name: 'remote_catalog', filename: 'remoteEntry.js', exposes: { './CatalogWidget': './src/CatalogWidget.tsx' }, shared: { react: { singleton: true, strictVersion: true, requiredVersion: packageJson.dependencies.react }, 'react-dom': { singleton: true, strictVersion: true, requiredVersion: packageJson.dependencies['react-dom'] } } }) ], build: { target: 'esnext', modulePreload: false, cssCodeSplit: true, rollupOptions: { output: { format: 'esm', entryFileNames: 'assets/[name]-[hash].js', chunkFileNames: 'assets/chunks/[name]-[hash].js', minifyInternalExports: false } } } }); ``` ### Runtime Remote Quarantine Barrier with Invariant Validation #### Bad Antipattern (AI Common Hallucination) > **Why it fails**: Directly loading the remote without verifying dispatcher compatibility or wrapping the component within an error quarantine boundary risks tearing down the entire host application lifecycle if a singleton mismatch or network bundle partition occurs. ```typescript import React, { lazy, Suspense } from 'react'; // ANTI-PATTERN: Blindly imports remote without checking reactive core integrity const RemoteCatalog = lazy(() => import('remote_catalog/CatalogWidget')); export const Container = () => ( <Suspense fallback={<div>Loading...</div>}> <RemoteCatalog /> </Suspense> ); ``` #### Production Standard (Correct) > **Standard**: Implements an isolated quarantine boundary that traps runtime microfrontend faults (including asynchronous bundle failures and dispatcher collisions) while programmatically validating remote ESM module exports prior to execution. ```typescript import React, { Component, ReactNode, Suspense, lazy } from 'react'; interface QuarantineProps { children: ReactNode; fallback: ReactNode; } interface QuarantineState { hasError: boolean; errorDetails: Error | null; } export class MicrofrontendQuarantineBoundary extends Component<QuarantineProps, QuarantineState> { override state: QuarantineState = { hasError: false, errorDetails: null }; static getDerivedStateFromError(error: Error): QuarantineState { return { hasError: true, errorDetails: error }; } override componentDidCatch(error: Error, errorInfo: React.ErrorInfo): void { console.error('[MFE Quarantine Engine] Remote isolation boundary failure:', error, errorInfo); } override render() { if (this.state.hasError) { return this.props.fallback; } return this.props.children; } } const SafeRemoteCatalog = lazy(async () => { // Invariant verification before mounting into host dispatcher tree const remoteModule = await import('remote_catalog/CatalogWidget'); if (!remoteModule || !remoteModule.default) { throw new Error('[MFE Quarantine] Malformed ESM bundle payload from remote_catalog'); } return remoteModule; }); export const Container: React.FC = () => ( <MicrofrontendQuarantineBoundary fallback={<div>Remote Micro-App Isolated Due To Collision</div>}> <Suspense fallback={<div>Loading Verified Remote...</div>}> <SafeRemoteCatalog /> </Suspense> </MicrofrontendQuarantineBoundary> ); ```

Architectural Specification & Invariant Rationale

Architectural Invariant Design: Vite 6 Dynamic Microfrontend Dependency Tree Isolation and Quarantine Standard

Vite 6 Dynamic Microfrontend Dependency Tree Isolation and Quarantine Standard defines an industrial-grade behavioral standard for frontend engineering. Enforces strict runtime module isolation, scoped dependency registries, and deterministic chunk deduplication across federated Vite 6 microfrontends. Prevents shared reactive core corruption (e.g., dual React Dispatcher instances, Vue reactive context splits) and unconstrained asynchronous vendor chunk collision across host and remote module boundaries. Modern software architectures require strict adherence to deterministic patterns to guarantee high availability, maintainability, and zero security vulnerabilities.

Framework Paradigm Shift & Drift MechanicsLLMs are trained on millions of open-source repositories containing outdated code, legacy idioms, and unpatched antipatterns. When coding assistants generate implementations for this stack, they default to common statistical tokens: Leaking Global Module Singletons and Unquarantined Asynchronous Vendor Chunks Across Micro-App Boundaries Without an explicit system instruction file, developers spend hours debugging silent failures.

Failure Modes & Production Blast Radius

Hazard Analysis: What Breaks Without This Rule

The following failure modes have been cataloged from hundreds of hours of production code reviews where AI assistants produced non-compliant implementations:

Failure Mode	AI Symptom (The Anti-Pattern)	Severity	Production Impact & Remedy
AI Hallucination & Deprecation Drift	Leaking Global Module Singletons and Unquarantined Asynchronous Vendor Chunks Across Micro-App Boundaries	Critical	Violating this industrial standard introduces regression bugs, security risks, and unexpected runtime failures in production. Enforce explicit behavioral system directives across all AI coding assistants in your repository.
Silent Architecture Inconsistency	AI assistants produce mixed paradigms across files, creating fragmented codebase conventions.	Medium	Increases cognitive load during code reviews and leads to maintenance debt across engineering teams. Pin project conventions in .cursor/rules, CLAUDE.md, and AGENTS.md so all team agents follow identical guardrails.

Architectural Directives in Detail

Step-by-Step Production Directives

Each rule constraint below is injected into the AI agent's system prompt to establish deterministic boundaries:

Engineers MUST ALWAYS configure Module Federation plugins with explicit shared configuration specifying 'singleton

Engineers MUST ALWAYS configure Module Federation plugins with explicit shared configuration specifying 'singleton: true' and 'strictVersion: true' for all reactive runtime cores (e.g., react, react-dom, @vue/runtime-core, rxjs).

Rationale:AI models frequently generate unconstrained code here because statistical language distributions lack project-specific architectural context. Mandating this directive ensures that generated code adheres to verified industrial production requirements.