mandu-performance

name	mandu-performance
description	Performance optimization patterns for Mandu applications. Use when optimizing slot handlers, Island components, bundle size, or Bun runtime. Triggers on tasks involving async/await, Promise.all, lazy loading, caching, or performance.
license	MIT
metadata	{"author":"mandu","version":"1.0.0"}

Mandu Performance

Mandu 애플리케이션의 성능 최적화 가이드. 워터폴 제거, 번들 최적화, 캐싱 패턴, Bun 런타임 활용법을 다룹니다. Vercel의 React Best Practices를 Mandu 컨텍스트로 변환하여 적용합니다.

Agent Workflow Contract

This skill is a Domain addendum. It must not replace mandu-agent-workflow. Use it only after mandu.agent.plan selects performance, hydration, route, API, or runtime domains.

Canonical workflow step: plan -> verify -> repair.

Preferred MCP tools:

Step	Tools
plan	mandu.agent.plan, mandu.agent.context
apply	mandu.agent.apply
verify	mandu.agent.verify, mandu.build, mandu.run.tests
repair	mandu.agent.repair

Allowed file edits:

• Route, slot, island, or cache code named in the plan
• Import boundaries that reduce bundle/runtime cost
• Benchmark/test files scoped to the performance claim

Verification command:

mandu agent verify --changed --json --write

Common failures:

• Optimizing without a measurable route, bundle, or runtime target
• Moving server-only code into client islands for convenience
• Skipping typecheck or targeted tests after cache/import rewrites

Repair path:

mandu agent repair --from .mandu/agent-verify.json --json

When to Apply

Reference these guidelines when:

• Optimizing slot handler response times
• Reducing Island component bundle size
• Implementing caching strategies
• Working with async/await patterns
• Leveraging Bun runtime features

Rule Categories by Priority

Priority	Category	Impact	Prefix
1	Async Optimization	CRITICAL	perf-async-
2	Bundle Optimization	CRITICAL	perf-bundle-
3	Caching Strategies	HIGH	perf-cache-
4	Bun Runtime	HIGH	perf-bun-
5	Rendering	MEDIUM	perf-render-

Quick Reference

1. Async Optimization (CRITICAL)

• perf-async-parallel - Use Promise.all() for independent operations
• perf-async-defer-await - Move await into branches where actually used
• perf-async-early-start - Start promises early, await late

2. Bundle Optimization (CRITICAL)

• perf-bundle-imports - Import directly, avoid barrel files
• perf-bundle-island-lazy - Lazy load Islands with dynamic import
• perf-bundle-preload - Preload on hover/focus for perceived speed

3. Caching Strategies (HIGH)

• perf-cache-slot - Cache slot responses with appropriate TTL
• perf-cache-react - Use React.cache() for request deduplication
• perf-cache-lru - Use LRU cache for cross-request caching

4. Bun Runtime (HIGH)

• perf-bun-serve - Optimize Bun.serve() configuration
• perf-bun-file - Use Bun.file() for efficient file operations
• perf-bun-sqlite - Leverage bun:sqlite for fast database access

5. Rendering (MEDIUM)

• perf-render-island-priority - Set appropriate hydration priority
• perf-render-transitions - Use startTransition for non-urgent updates

Performance Impact Summary

Optimization	Typical Improvement
Promise.all()	2-10× faster
Direct imports	15-70% faster dev boot
Island lazy loading	40-60% smaller initial bundle
React.cache()	Eliminates duplicate queries
Bun.file()	10× faster than Node fs

How to Use

Read individual rule files for detailed explanations:

rules/perf-async-parallel.md
rules/perf-bundle-imports.md
rules/perf-bun-serve.md