Vercel

• One key per Vercel project. Each project you choose gets its own Sending access API key, which can send email and nothing else: it cannot read your emails, contacts or settings.
• Saved as RASKET_API_KEY, encrypted, on the Production, Preview and Development environments. If the project already has a variable by that name, it is replaced.
• A Rasket project per Vercel project. Send every Vercel project from one Rasket project, or choose one for each. Each sends from its Rasket project's verified domains, on its plan, and its emails show in that project.
• Nothing to pay on Vercel. Vercel bills nothing for Rasket; your Rasket plan is the only plan.

• An admin of each Rasket project you choose, with a verified email address. The keys belong to the whole project, so a member who is not an admin cannot connect it. You can also create a new Rasket project while you connect.
• A verified sending domain, to send from. The key works without one, but every send is refused until the domain is verified. The domains guide walks through it.
• Up to 25 Vercel projects per install. Choose the projects that send email rather than all of them.

1. In Rasket, open Settings, then Integrations, then Vercel, and choose Add Rasket on Vercel.
2. On Vercel, choose the Vercel team, then Specific projects and the projects that should send email, and install.
3. Rasket opens. Sign in, or create an account. Rasket names the Vercel account and every project the install reaches. Only continue if you have just added Rasket on Vercel yourself.
4. Choose where the projects send from. Send all from puts every Vercel project on one Rasket project. Choose per project gives each its own, and any of them can be + New project, a new Rasket project named after the Vercel project. Then choose Connect.
5. Rasket lists each Vercel project and the Rasket project it sends from. A new project needs a verified domain before it can send; the page links to its Domains page. Choose Back to Vercel.
6. Redeploy each project. A deployment reads its environment variables when it is built, so one built before you connected has no key.

Finish within 30 minutes of choosing install on Vercel. After that, the install expires and nothing is written; add Rasket again. The admins of each Rasket project get one email saying new keys were created there.

Read the key from process.env.RASKET_API_KEY in server code only. Never copy it into a variable your framework exposes to the browser, such as one that starts with NEXT_PUBLIC_.

// app/api/welcome/route.ts
export async function POST(request: Request) {
  const { email } = (await request.json()) as { email: string };
  const response = await fetch("https://api.rasket.com/emails", {
    method: "POST",
    headers: {
      Authorization: `Bearer ${process.env.RASKET_API_KEY}`,
      "User-Agent": "acme-billing/1.0",
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      from: "Acme <hello@example.com>",
      to: email,
      subject: "Welcome to Acme",
      html: "<p>Thanks for signing up.</p>",
    }),
  });
  return Response.json(await response.json(), { status: response.status });
}

Send a User-Agent: a request with no User-Agent is refused. Use an address on your verified domain in from. The emails reference has every field a send takes.

// app/actions.ts
"use server";

export async function sendWelcome(formData: FormData) {
  const email = String(formData.get("email"));
  const response = await fetch("https://api.rasket.com/emails", {
    method: "POST",
    headers: {
      Authorization: `Bearer ${process.env.RASKET_API_KEY}`,
      "User-Agent": "acme-billing/1.0",
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      from: "Acme <hello@example.com>",
      to: email,
      subject: "Welcome to Acme",
      html: "<p>Thanks for signing up.</p>",
    }),
  });
  if (!response.ok) {
    throw new Error(`The welcome email was not sent (${response.status}).`);
  }
}

A server action runs on the server, so it reads RASKET_API_KEY the same way. Call it from a form's action.

The Development environment has the key too, so the Vercel CLI can bring it to your machine:

vercel env pull .env.local

Keep .env.local out of version control. Next.js reads it when you run next dev.

• See your installs under Settings → Integrations → Vercel in each Rasket project: the Vercel projects that send from it and the start of each key. On Vercel, the integration's Configure button opens that page for the first of your Rasket projects in the install.
• Adding Rasket again to the same projects replaces each key: the new one is saved first, then the old one is revoked, even when you choose a different Rasket project this time. Redeploy afterwards, because deployments built with the old key can no longer send.
• Projects added later are not picked up. Giving the install more projects on Vercel writes no key into them. Disconnect, then add Rasket again with the projects you want.
• A deleted Vercel project's key stays live until you disconnect the install it came from.

• In Rasket, an admin chooses Disconnect on Settings → Integrations → Vercel. Rasket revokes the keys of the Vercel projects that send from that Rasket project and removes RASKET_API_KEY from them. If no Vercel project in the install sends from another Rasket project, it also removes the integration from the Vercel account. The page says which it will do.
• On Vercel, remove the Rasket integration. Rasket revokes every key the install created, in every Rasket project, when Vercel tells it.

Revoked keys stop working at once, including in deployments that are already running. Keys you created yourself under API keys are not touched.