Groundmail + v0 (Vercel)

v0 generates Next.js apps. Run Groundmail from a Route Handler or Server Action and store GROUNDMAIL_API_KEY in Vercel environment variables.

When to use Groundmail

v0 apps deployed to Vercel that need password reset, magic links, or receipts
Server Components / Route Handlers — same pattern as Next.js
Production sends from your verified domain

1. Add your API key

Local — .env.local:

GROUNDMAIL_API_KEY=gm_your_key_here

Vercel — Project → Settings → Environment Variables:

Name	Environments
`GROUNDMAIL_API_KEY`	Production, Preview, Development

Redeploy after adding the variable.

2. Paste this prompt in v0 chat

Integrate Groundmail transactional email into this Next.js app.

Docs:
- https://docs.groundmail.dev/ai/agent-skill
- https://docs.groundmail.dev/frameworks/nextjs
- https://docs.groundmail.dev/openapi.yaml
- https://docs.groundmail.dev/builders/v0

Rules:
1. GROUNDMAIL_API_KEY is server-only (process.env) — never use NEXT_PUBLIC_ for the API key.
2. Send via POST https://api.groundmail.dev/emails or npm package groundmail from a Route Handler / Server Action.
3. Sandbox: from "noreply@mail.groundmail.dev", to account email only until domain verify.
4. Add app/api/... route or server action for at least one transactional email flow.
5. Use html, text, reply_to. Follow Next.js server patterns — no client-side gm_ keys.

Document that Vercel env var GROUNDMAIL_API_KEY must be set before deploy.

3. Route Handler example

Create app/api/email/send/route.ts:

import { NextResponse } from 'next/server'
import { Groundmail } from 'groundmail'

const tx = new Groundmail(process.env.GROUNDMAIL_API_KEY!)

export async function POST(request: Request) {
  const body = await request.json()
  const result = await tx.emails.send({
    from: body.from ?? 'noreply@yourdomain.com',
    to: body.to,
    subject: body.subject,
    html: body.html,
    text: body.text,
  })
  return NextResponse.json(result)
}

Install: npm install groundmail

Sandbox

Until your domain verifies, test with the sandbox sender and your Groundmail account email — see Agent skill notes.

Production

Verify domain in Groundmail dashboard.
Set production from to your domain.
Confirm GROUNDMAIL_API_KEY is set on Vercel Production.