Serverless / Vercel

Nebula targets Node.js servers. It depends on native addons:

• sharp
• @resvg/resvg-js

Those packages do not run in the browser or typical Edge/WASM runtimes.

Practical checklist

1. Use a Node.js runtime (e.g. Vercel Node serverless functions / App Router runtime = 'nodejs').
2. Bundle or include platform-correct native binaries for your deploy OS/arch (Linux x64 is common on Vercel).
3. Watch memory and timeout — large tables and high devicePixelRatio increase PNG size and work.
4. Prefer embedding fonts as Buffers loaded at cold start (or from the function bundle), not from remote URLs on every request.
5. Keep devicePixelRatio at 1 or 2 for colder / smaller functions.

Vercel App Router sketch

export const runtime = 'nodejs';
export const maxDuration = 30;

// Same pattern as Next.js: engine.generate → Response(pdf, { headers })

What not to expect

• Edge Middleware / Edge Functions
• Cloudflare Workers without a Node-compatible native strategy
• Bundlephobia-style “browser bundle size” metrics (native deps cannot be browser-bundled)

See also

• Next.js
• Why Nebula PDF