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Pulse ae39e45460 feat: biblioteca inteligente libs/ + 5 novas skills (20 skills total)

NOVAS SKILLS:
- next-best-practices      v0.1.0  (CLEAN) — Next.js App Router, RSC, caching, data
- nextjs-patterns          v1.0.0  (CLEAN) — Next.js 15: Server Actions, route handlers
- vite                     v1.0.0  (CLEAN) — env vars, aliases, proxy, CJS compat
- uncle-bob                v1.0.0  (CLEAN) — Clean Code, SOLID, Clean Architecture
- clean-code-review        v1.0.0  (CLEAN) — naming, guard clauses, anti-patterns, refactoring
- vue                      v1.0.0  (CLEAN) — Vue framework
- vue-composition-api-best-practices v1.0.0 (CLEAN) — composables, Pinia, reactivity

BIBLIOTECA INTELIGENTE libs/ (10 dominios, 11 arquivos):
- typescript/ — TS safe + generics gotchas
- react/ — Next.js App Router + Vite config
- vue/ — Composition API + Pinia
- linux/ — System diagnostic cheatsheet
- database/ — PostgreSQL + MySQL patterns
- browser/ — Chromium CLI + E2E testing
- security/ — SAST audit (OWASP Top 10)
- best-practices/ — Clean Code + SOLID + Clean Architecture
- deploy/ — Docker multi-stack + OpenClaw ops
- + INDEX.md como guia de navegacao

.learnings/ — LRN-20260519-003 criado (biblioteca compartilhada)

2026-05-19 21:03:25 -03:00

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Hydration Errors

Diagnose and fix React hydration mismatch errors.

Error Signs

"Hydration failed because the initial UI does not match"
"Text content does not match server-rendered HTML"

Debugging

In development, click the hydration error to see the server/client diff.

Common Causes and Fixes

Browser-only APIs

// Bad: Causes mismatch - window doesn't exist on server
<div>{window.innerWidth}</div>

// Good: Use client component with mounted check
'use client'
import { useState, useEffect } from 'react'

export function ClientOnly({ children }: { children: React.ReactNode }) {
  const [mounted, setMounted] = useState(false)
  useEffect(() => setMounted(true), [])
  return mounted ? children : null
}

Date/Time Rendering

Server and client may be in different timezones:

// Bad: Causes mismatch
<span>{new Date().toLocaleString()}</span>

// Good: Render on client only
'use client'
const [time, setTime] = useState<string>()
useEffect(() => setTime(new Date().toLocaleString()), [])

Random Values or IDs

// Bad: Random values differ between server and client
<div id={Math.random().toString()}>

// Good: Use useId hook
import { useId } from 'react'

function Input() {
  const id = useId()
  return <input id={id} />
}

Invalid HTML Nesting

// Bad: Invalid - div inside p
<p><div>Content</div></p>

// Bad: Invalid - p inside p
<p><p>Nested</p></p>

// Good: Valid nesting
<div><p>Content</p></div>

Third-party Scripts

Scripts that modify DOM during hydration.

// Good: Use next/script with afterInteractive
import Script from 'next/script'

export default function Page() {
  return (
    <Script
      src="https://example.com/script.js"
      strategy="afterInteractive"
    />
  )
}

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