@react-pdf/renderer crashes when used via external package in Next.js App Router (monorepo)

[alekseykurylev]

When using @react-pdf/renderer in a Next.js App Router project via an external package (e.g. from a monorepo), PDF generation fails at runtime.

However, the same code works correctly if @react-pdf/renderer is installed directly in the Next.js application.

TypeError: Cannot read properties of undefined (reading 'S')

Thrown during renderToStream.

Environment
• Next.js: 15 (App Router)
• React: 19
• Node.js: 22
• Monorepo: Turborepo
• Package manager: pnpm
• @react-pdf/renderer: 4.3.2

Project structure

apps/
  web/               ← Next.js App Router app
packages/
  pdf/               ← custom package wrapping @react-pdf/renderer

packages/pdf exports React components based on @react-pdf/renderer:

// packages/pdf/components.ts
export { Document, Page, Text } from "@react-pdf/renderer";

❌ Failing case (renderer used via external package)

// apps/web/app/api/pdf/route.tsx
import { Document, Page, Text } from "@repo/pdf/components";
import { renderToStream } from "@repo/pdf/server";

export async function GET() {
  const stream = await renderToStream(
    <Document>
      <Page>
        <Text>Hello</Text>
      </Page>
    </Document>
  );

  return new Response(stream);
}

Result:

TypeError: Cannot read properties of undefined (reading 'S')

✅ Working case (renderer installed in app)

// apps/web/app/api/pdf/route.tsx
import { Document, Page, Text, renderToStream } from "@react-pdf/renderer";

export async function GET() {
  const stream = await renderToStream(
    <Document>
      <Page>
        <Text>Hello</Text>
      </Page>
    </Document>
  );

  return new Response(stream);
}

✅ Works without errors.

Key observation
• JSX, runtime, and code are identical
• Only difference:
• ❌ @react-pdf/renderer resolved from external package
• ✅ @react-pdf/renderer resolved from Next.js app itself

This indicates a possible issue with:
• multiple React renderers / reconciler instances
• module resolution in monorepos
• assumptions inside @react-pdf/renderer about React element identity
• interaction with Next.js App Router (RSC)