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Runtime Selection

Use Node.js Runtime by Default

Use the default Node.js runtime for new routes and pages. Only use Edge runtime if the project already uses it or there's a specific requirement.

// Good: Default - no runtime config needed (uses Node.js)
export default function Page() { ... }

// Caution: Only if already used in project or specifically required
export const runtime = 'edge'

When to Use Each

Node.js Runtime (Default)

  • Full Node.js API support
  • File system access (fs)
  • Full crypto support
  • Database connections
  • Most npm packages work

Edge Runtime

  • Only for specific edge-location latency requirements
  • Limited API (no fs, limited crypto)
  • Smaller cold start
  • Geographic distribution needs

Detection

Before adding runtime = 'edge', check:

  1. Does the project already use Edge runtime?
  2. Is there a specific latency requirement?
  3. Are all dependencies Edge-compatible?

If unsure, use Node.js runtime.