Multi-Surface Rendering with json-render
Define once, render everywhere. A single json-render catalog and spec can produce React web UIs, PDF reports, HTML emails, Remotion demo videos, and OG images — each surface gets its own registry that maps catalog types to platform-native components.
Quick Reference
| Category | Rules | Impact | When to Use | |----------|-------|--------|-------------| | Target Selection | 1 | HIGH | Choosing which renderer for your use case | | React Renderer | 1 | MEDIUM | Web apps, SPAs, dashboards | | PDF & Email Renderer | 1 | HIGH | Reports, documents, notifications | | Video & Image Renderer | 1 | MEDIUM | Demo videos, OG images, social cards | | Registry Mapping | 1 | HIGH | Platform-specific component implementations |
Total: 5 rules across 5 categories
How Multi-Surface Rendering Works
- One catalog — Zod-typed component definitions shared across all surfaces
- One spec — flat-tree JSON/YAML describing the UI structure
- Many registries — each surface maps catalog types to its own component implementations
- Many renderers — each package renders the spec using its registry
The catalog is the contract. The spec is the data. The registry is the platform-specific implementation.
Quick Start — Same Catalog, Different Renderers
Shared Catalog (used by all surfaces)
import { defineCatalog } from '@json-render/core'
import { schema } from '@json-render/react/schema'
import { z } from 'zod'
export const catalog = defineCatalog(schema, {
components: {
Heading: {
props: z.object({
text: z.string(),
level: z.enum(['h1', 'h2', 'h3']),
}),
children: false,
},
Paragraph: {
props: z.object({ text: z.string() }),
children: false,
},
StatCard: {
props: z.object({
label: z.string(),
value: z.string(),
trend: z.enum(['up', 'down', 'flat']).optional(),
}),
children: false,
},
},
})
Render to Web (React)
import { Renderer } from '@json-render/react'
import { webRegistry } from './registries/web'
// webRegistry comes from `defineRegistry(catalog, { components })`.
// RendererProps is { spec, registry, loading?, fallback? } — no catalog prop.
export const Dashboard = ({ spec }) => (
<Renderer spec={spec} registry={webRegistry} />
)
Render to PDF
import { renderToBuffer, renderToFile } from '@json-render/react-pdf'
import { pdfRegistry } from './registries/pdf'
// Buffer for HTTP response. PDF options are { registry?, state?, handlers? }.
// includeStandard is an EMAIL option, not a PDF one (see references/upstream-pdf.md).
const buffer = await renderToBuffer(spec, { registry: pdfRegistry })
// Direct file output — renderToFile(spec, filePath, options?)
await renderToFile(spec, './output/report.pdf', { registry: pdfRegistry })
Render to Email
import { renderToHtml } from '@json-render/react-email'
import { emailRegistry } from './registries/email'
const html = await renderToHtml(spec, { registry: emailRegistry })
await sendEmail({ to: user.email, subject: 'Weekly Report', html })
Render to OG Image (Satori)
import { renderToSvg, renderToPng } from '@json-render/image'
import { imageRegistry } from './registries/image'
const png = await renderToPng(spec, {
registry: imageRegistry,
width: 1200,
height: 630,
})
Render to Video (Remotion)
// Verified 2026-07-31 against @json-render/remotion@0.19.0: the export is
// `Renderer` and its props are { spec, components }. fps and durationInFrames
// belong on Remotion's own Composition, not on this renderer.
import { Renderer } from '@json-render/remotion'
import { remotionComponents } from './registries/remotion'
export const DemoVideo = () => (
<Renderer spec={spec} components={remotionComponents} />
)
Render to Terminal (Ink, 0.15+)
import { render } from 'ink'
import { Renderer } from '@json-render/ink'
import { catalog } from './catalog'
import { inkRegistry } from './registries/ink'
render(<Renderer spec={spec} catalog={catalog} registry={inkRegistry} />)
Useful for /ork:* CLI dashboards and streaming agent chat interfaces — ships 20+ Ink-native components (Box, Text, Spinner, Table, Markdown, Progress, etc.).
Render to Next.js App (0.16+)
// createNextApp lives on the /server subpath, not the package root.
import { createNextApp } from '@json-render/next/server'
const { getPageData, generateMetadata, generateStaticParams } = createNextApp({
spec, // NextAppSpec: routes keyed by Next.js URL patterns
loaders: { getPost }, // server-side data loaders referenced by route.loader
})
It does not scaffold a project on disk. createNextApp returns the server-side pieces you
re-export from a catch-all route, and the page itself renders through PageRenderer:
// app/[[...slug]]/page.tsx
export { generateMetadata, generateStaticParams }
export default async function Page({ params }) {
const data = await getPageData(params)
if (!data) notFound()
return <PageRenderer {...data} registry={webRegistry} />
}
A spec describes a route tree (pages, layouts, metadata, loading and error states), not just a component tree.
Decision Matrix — When to Use Each Target
| Target | Package | When to Use | Output |
|--------|---------|-------------|--------|
| React | @json-render/react | Web apps, SPAs | JSX |
| Next.js | @json-render/next (0.16+) | Full apps: routes, layouts, SSR, metadata | Next.js app |
| Vue | @json-render/vue | Vue projects | Vue components |
| Svelte | @json-render/svelte | Svelte projects | Svelte components |
| Svelte+shadcn | @json-render/shadcn-svelte (0.16+) | 36-component Svelte 5 catalog | Svelte + Tailwind |
| React Native | @json-render/react-native | Mobile apps (25+ components) | Native views |
| Terminal | @json-render/ink (0.15+) | CLI UIs, TUIs, streaming chat | Ink (terminal) |
| PDF | @json-render/react-pdf | Reports, documents | PDF buffer/file |
| Email | @json-render/react-email | Notifications, digests | HTML string |
| Remotion | @json-render/remotion | Demo videos, marketing | MP4/WebM |
| Image | @json-render/image | OG images, social cards | SVG/PNG (Satori) |
| YAML | @json-render/yaml (0.14+) | Token optimization, streaming parser | YAML string |
| MCP | @json-render/mcp | Claude/Cursor/ChatGPT conversations | Sandboxed iframe |
| 3D | @json-render/react-three-fiber | 3D scenes (19 components, verified 2026-07-31; roster lives upstream) | Three.js canvas |
| Codegen | @json-render/codegen | Source code from specs | TypeScript/JSX |
All @json-render/* renderers are verified against 0.19.0 (@json-render/core).
Load rules/target-selection.md for detailed selection criteria and trade-offs.
Upstream coverage (do not restate)
This skill wraps @json-render/*. Vendor documentation is fetched, not repeated. What survives here
is the house delta: references/ork-delta.md plus the five rules.
| Topic | Source |
|-------|--------|
| Full renderer signatures and option objects (renderToBuffer / renderToFile / renderToStream, renderToHtml / renderToPlainText, renderToSvg / renderToPng, Remotion exports) | references/upstream-pdf.md, upstream-email.md, upstream-image.md, upstream-remotion.md (vendored verbatim; re-sync with bash scripts/sync-vercel-skills.sh) |
| Standard component rosters per target (Document, Page, Table, email Section / Row / Column, Remotion transitions and effects) | the same four vendored references/upstream-*.md files |
| <Renderer> props, defineRegistry, useUIStream | https://github.com/vercel-labs/json-render/tree/main/packages/react. The 0.19 prop-shape correction (no catalog prop, no top-level onError) is a house finding and stays in rules/react-renderer.md |
| Email client constraints: 600px container, table layout, inline styles, absolute image URLs | references/upstream-email.md ("Email Best Practices") |
| Satori CSS support matrix | https://github.com/vercel/satori. The working subset this skill designs image registries against stays in rules/video-image-renderer.md |
| react-pdf style property support (flexbox set, no grid) | https://react-pdf.org/styling |
| Remotion render cost and cloud rendering | https://www.remotion.dev/docs/lambda |
| Per-package capability and output matrix | the house target picks stay in the Decision Matrix above and in rules/target-selection.md; per-package detail at https://github.com/vercel-labs/json-render |
Read references/ork-delta.md before writing renderer code: it carries the API-drift rule, the
Remotion and PDF latency budgets, and the PDF / React Native registry layout ceiling.
PDF Renderer — Reports and Documents
The @json-render/react-pdf package renders specs to PDF using react-pdf under the hood. Three output modes: buffer, file, and stream.
import { renderToBuffer, renderToFile, renderToStream } from '@json-render/react-pdf'
// In-memory buffer (for HTTP responses, S3 upload)
// PDF options are { registry?, state?, handlers? }, no catalog field
const buffer = await renderToBuffer(spec, { registry: pdfRegistry })
res.setHeader('Content-Type', 'application/pdf')
res.send(buffer)
// Direct file write — renderToFile(spec, filePath, options?)
await renderToFile(spec, './output/report.pdf', { registry: pdfRegistry })
// Streaming (for large documents)
const stream = await renderToStream(spec, { registry: pdfRegistry })
stream.pipe(res)
Load rules/pdf-email-renderer.md for PDF registry patterns and email rendering.
Image Renderer — OG Images and Social Cards
The @json-render/image package uses Satori to convert specs to SVG, then optionally to PNG. Designed for server-side generation of social media images.
import { renderToSvg, renderToPng } from '@json-render/image'
// SVG output (smaller, scalable)
const svg = await renderToSvg(spec, {
registry: imageRegistry,
width: 1200,
height: 630,
})
// PNG output (universal compatibility)
const png = await renderToPng(spec, {
registry: imageRegistry,
width: 1200,
height: 630,
})
Load rules/video-image-renderer.md for Satori constraints and Remotion composition patterns.
Registry Mapping — Same Catalog, Platform-Specific Components
Each surface needs its own registry. The registry maps catalog types to platform-specific component implementations while the catalog and spec stay identical.
// Web registry — uses HTML elements
const webRegistry = {
Heading: ({ text, level }) => {
const Tag = level // h1, h2, h3
return <Tag className="font-bold">{text}</Tag>
},
StatCard: ({ label, value, trend }) => (
<div className="rounded border p-4">
<span className="text-sm text-gray-500">{label}</span>
<strong className="text-2xl">{value}</strong>
</div>
),
}
// PDF registry — uses react-pdf primitives
import { Text, View } from '@react-pdf/renderer'
const pdfRegistry = {
Heading: ({ text, level }) => (
<Text style={{ fontSize: level === 'h1' ? 24 : level === 'h2' ? 18 : 14 }}>
{text}
</Text>
),
StatCard: ({ label, value }) => (
<View style={{ border: '1pt solid #ccc', padding: 8 }}>
<Text style={{ fontSize: 10, color: '#666' }}>{label}</Text>
<Text style={{ fontSize: 18, fontWeight: 'bold' }}>{value}</Text>
</View>
),
}
Load rules/registry-mapping.md for registry creation patterns and type safety.
Rule Details
Target Selection
Decision criteria for choosing the right renderer target.
| Rule | File | Key Pattern |
|------|------|-------------|
| Target Selection | rules/target-selection.md | Use case mapping, output format constraints |
React Renderer
Web rendering with the <Renderer> component.
| Rule | File | Key Pattern |
|------|------|-------------|
| React Renderer | rules/react-renderer.md | <Renderer> component, streaming, error boundaries |
PDF & Email Renderer
Server-side rendering to PDF buffers/files and HTML email strings.
| Rule | File | Key Pattern |
|------|------|-------------|
| PDF & Email | rules/pdf-email-renderer.md | renderToBuffer, renderToFile, renderToHtml |
Video & Image Renderer
Remotion compositions and Satori image generation.
| Rule | File | Key Pattern |
|------|------|-------------|
| Video & Image | rules/video-image-renderer.md | Renderer (Remotion), renderToPng, renderToSvg |
Registry Mapping
Creating platform-specific registries for a shared catalog.
| Rule | File | Key Pattern |
|------|------|-------------|
| Registry Mapping | rules/registry-mapping.md | Per-platform registries, type-safe mapping |
Key Decisions
| Decision | Recommendation |
|----------|----------------|
| PDF library | Use @json-render/react-pdf (react-pdf), not Puppeteer screenshots |
| Email rendering | Use @json-render/react-email (react-email), not MJML or custom HTML |
| OG images | Use @json-render/image (Satori), not Puppeteer or canvas |
| Video | Use @json-render/remotion (Remotion), not FFmpeg scripts |
| Registry per platform | Always separate registries; never one registry for all surfaces |
| Catalog sharing | One catalog definition shared via import across all registries |
Common Mistakes
- Building separate component trees for each surface — defeats the purpose; share the catalog and spec
- Using Puppeteer to screenshot React for PDF generation — slow, fragile; use native react-pdf rendering
- One giant registry covering all platforms — impossible since PDF uses
<View>/<Text>, web uses<div>/<span> - Forgetting Satori limitations — no CSS grid, limited flexbox; design image registries with these constraints
- Duplicating catalog definitions per surface — one catalog, many registries; the catalog is the contract
Related Skills
ork:json-render-catalog— Catalog definition patterns with Zod, shadcn componentsork:demo-producer— Video production pipeline using Remotionork:mcp-visual-output— Rendering specs in Claude/Cursor via MCP