Bundle size optimization

docs/PRDs/212-bundle-size-optimization.md から始め、Webpack Bundle Analyzer などのバンドル分析ツールを使用して、現在のフロントエンドおよびバックエンドのバンドルを分析します。分析で特定された SvelteKit/Svelte 5 のコンポーネント、依存関係、アセット、Node.js パッケージを確認し、既存のテストと Lighthouse で検証します。完了の条件は、機能、セキュリティ、エラー率に関するリグレッションを発生させずに、バンドルサイズを少なくとも 20% 削減することです。

📋 Product Requirements Document

PRD: Bundle size optimization

Issue: #212
Milestone: Phase 10: Polish & Launch
Labels: performance-optimization, hacktoberfest

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PRD: Bundle Size Optimization

Overview

This document outlines the plan for optimizing the bundle size of MeshHook, an essential step within the project's Phase 10: Polish & Launch. This optimization aims to enhance MeshHook's performance by reducing load times, thereby improving user experience without compromising the application's functionality, security, or performance. This initiative aligns with MeshHook's goals of delivering an efficient, performant, and user-friendly workflow engine.

Objective: Achieve a significant reduction in the bundle size of MeshHook's frontend (SvelteKit/Svelte 5) and backend components, ensuring no loss in functionality, security, or performance.

Functional Requirements

1. Bundle Analysis: Conduct a thorough analysis of the current bundle to identify large dependencies and areas for optimization.
2. Code Splitting: Implement code splitting and lazy loading for SvelteKit/Svelte 5 components to load only necessary parts of the application.
3. Dependency Optimization: Evaluate and substitute heavy third-party libraries with lighter alternatives without losing essential functionality.
4. Asset Optimization: Utilize advanced asset optimization strategies, including image compression, and minification of CSS and JavaScript files.
5. Testing and Validation: Ensure optimizations do not alter existing functionalities, maintaining the responsiveness and user experience of the visual DAG builder and other interfaces.

Non-Functional Requirements

• Performance: Target at least a 20% reduction in overall bundle size to contribute to faster application load times.
• Reliability: Ensure optimization efforts do not introduce bugs or regressions.
• Security: Maintain adherence to MeshHook's security guidelines, using secure and up-to-date libraries.
• Maintainability: Code after optimization should remain clean, well-documented, and easy to maintain.

Technical Specifications

Architecture Context

MeshHook uses SvelteKit for its frontend and Supabase (including Postgres and Realtime) for backend services. The optimization strategy should cover both areas, focusing on reducing the bundle size while maintaining the integrity and performance of the system.

Implementation Approach

1. Bundle Analysis: Use tools like Webpack Bundle Analyzer to identify large dependencies. Audit current library and framework usage to eliminate unnecessary imports.
2. Optimization Techniques:
   • Implement dynamic imports and code splitting for SvelteKit components.
   • Replace heavy third-party libraries with lighter alternatives.
   • Compress images and static assets; minify CSS and JavaScript files.
   • Utilize tree shaking and dead code elimination.
   • Optimize backend dependencies focusing on Node.js packages.
3. Validation: Conduct rigorous testing across development, staging, and production environments to ensure functional integrity. Monitor performance metrics pre and post-optimization.

Data Model and API Endpoints

No anticipated changes to data models or API endpoints. The focus is on optimization without altering existing data structures or API contracts.

Acceptance Criteria

• At least a 20% reduction in overall bundle size without loss of functionality.
• Improved application load times on both desktop and mobile platforms.
• No degradation in function, including visual DAG builder and workflow capabilities.
• Unaffected error rates and security posture post-optimization.
• Updated documentation reflecting dependency changes or optimization strategies.

Dependencies

• Access to MeshHook's current codebase and infrastructure.
• Tools for bundle analysis and optimization (e.g., Webpack Bundle Analyzer).
• Approval for significant changes in used libraries or frameworks.

Implementation Notes

Development Guidelines

• Favor lightweight, secure libraries with strong community support.
• Emphasize a mobile-first approach to enhance performance across devices.
• Asynchronous loading for non-essential components and libraries is encouraged.

Testing Strategy

• Extensive testing, including unit, integration, and end-to-end tests, to ensure no negative impact on existing functionalities.
• Use performance testing tools (e.g., Lighthouse) to measure improvements in loading times and overall performance.

Security Considerations

• Assess new libraries or dependencies for security vulnerabilities.
• Ensure optimizations do not expose sensitive data or compromise the application's security.

Monitoring & Observability

• Implement detailed logging and monitoring to track performance improvements and identify potential regressions.
• Compare error rates and response times before and after optimization efforts to measure effectiveness.

By adhering to this PRD, we aim to optimize MeshHook's bundle size effectively, ensuring the project continues to meet its goals of delivering a high-performance, efficient, and user-friendly workflow engine.

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This PRD was AI-generated using gpt-4-turbo-preview from GitHub issue #212
Generated: 2025-10-10

📎 Generated Documentation

• 📄 PRD Document: 212-bundle-size-optimization.md
• 🎨 PlantUML Diagram: 212-bundle-size-optimization.puml
• 🖼️ Diagram Image: 212-bundle-size-optimization.png

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This issue body was auto-generated from the PRD. Original issue content is preserved in the PRD document.
Last updated: 2025-10-10