RSC Data Fetching Optimizer

Optimize slow client-side data fetching to instant server-side rendering.

Quick Diagnosis

Search for these anti-patterns in the codebase:

Find client-side fetching patterns

rg -n "useEffect.fetch|useState.loading|useStore()" --type tsx rg -n '"use client"' app/ --type tsx

Red flags:

"use client" + useEffect + fetch() = slow initial load useState(true) for isLoading = user sees spinner useStore() or useContext for initial page data = waterfall fetching 3-Step Conversion Workflow Step 1: Identify Data Requirements

Determine what data the page needs on initial render:

Static/rarely-changing data → Server Component (SSR) User-interactive data (filters, search) → Client Component Step 2: Extract Interactive Sections

Move sections with useInView, useState, onClick to separate Client Components:

// components/data-section.tsx "use client";

interface DataSectionProps { data: Item[]; // Receive data as props }

export function DataSection({ data }: DataSectionProps) { const [ref, inView] = useInView(); // Client-side animation OK return

Step 3: Convert Page to Server Component // app/page.tsx - NO "use client" import { getData } from "@/lib/actions/data"; import { DataSection } from "@/components/data-section";

export default async function Page() { const data = await getData(); // Fetch on server return ; }

Type Adapter Pattern

When DB types differ from frontend types:

import type { Item as DBItem } from "@/lib/database.types"; import type { Item } from "@/lib/types";

function adaptDBToFrontend(db: DBItem): Item { return { id: db.id, name: db.name, description: db.description ?? "", createdAt: new Date(db.created_at), }; }

export default async function Page() { const dbItems = await getItems(); const items = dbItems.map(adaptDBToFrontend); return ; }

When to Keep Client-Side

Keep "use client" when:

Real-time subscriptions (Supabase realtime) User-triggered fetching (search, filters, pagination) Data depends on client state (auth token, localStorage) Infinite scroll / load more patterns Advanced Patterns

See references/patterns.md for:

Parallel data fetching Streaming with Suspense Error boundaries Caching strategies Hybrid SSR + client patterns