mailfleet

Official SDK for MailFleet — the transactional email API without the enterprise tax.

• 50,000 emails for $10/month (free tier: 3,000/month, no card)
• SAML/SSO, audit logs and SLA at $99/month — a checkbox, not a sales call
• Per-customer sender isolation on AWS SES: someone else's bad list can't hurt your deliverability
• Zero-dependency SDK. Node 18+, serverless, edge, Bun, Deno.

Install

npm install mailfleet

Quickstart

import { MailFleet } from "mailfleet";

const mailfleet = new MailFleet(process.env.MAILFLEET_API_KEY!);

const { id } = await mailfleet.send({
  from: "Acme <[email protected]>",   // a domain you verified in the dashboard
  to: "[email protected]",       // string or array, up to 50
  subject: "Your receipt",
  html: "<p>Thanks for your order!</p>",
});

Get an API key in three steps: sign up (free), verify your sending domain (3 DKIM CNAME records, shown in the dashboard), create a key. ~5 minutes end to end — full docs.

Sending

await mailfleet.send({
  from: "Acme <[email protected]>",
  to: ["[email protected]", "[email protected]"],
  subject: "Maintenance window tonight",
  text: "We'll be offline 02:00–02:15 UTC.",
  replyTo: "[email protected]",
});

At least one of html / text is required. from must use a verified domain.

Error handling

Every failure throws a typed MailFleetError with a machine-readable code:

import { MailFleet, MailFleetError } from "mailfleet";

try {
  await mailfleet.send({ ... });
} catch (e) {
  if (e instanceof MailFleetError) {
    switch (e.code) {
      case "quota_exceeded":       // plan limit reached — e.limit tells you the cap
      case "domain_not_verified":  // finish DNS verification in the dashboard
      case "account_paused":       // deliverability protection kicked in
      case "invalid_api_key":
      default:                     // validation_error | all_recipients_suppressed | send_failed | network_error
    }
  }
}

| code | HTTP | meaning | | --- | --- | --- | | invalid_api_key | 401 | Missing/revoked key | | validation_error | 422 | Bad request shape (fields, recipient count) | | domain_not_verified | 403 | from domain isn't verified for your account | | account_paused | 403 | Bounce/complaint thresholds exceeded — deliverability protection | | quota_exceeded | 429 | Monthly plan limit reached (error.limit = your cap) | | all_recipients_suppressed | 422 | Every recipient previously hard-bounced or complained | | send_failed | 502 | Upstream provider error |

Hard-bouncing and complaining addresses are suppressed automatically — MailFleet protects your sender reputation by default.

Why MailFleet

MailFleet is built for product email — receipts, magic links, verification codes, alerts. Transparent flat pricing, no deliverability add-on upsells, and the enterprise checkboxes (SAML/SSO, audit logs, SLA) on a self-serve $99 plan. Comparisons: vs Resend · vs SendGrid.

Links

Docs · Pricing · Acceptable use · [email protected]

MIT © MailFleet