@effect-kit/emails

Email for Effect.

One Email service for 16 providers. Every message is checked against the provider before it is sent.

Read the docs GitHub

Before it leaves

If the provider can't carry it, it isn't sent.

An attachment through MailerSend fails with UnsupportedFeatureError. No request is made.

01Providers

Change the provider, not the program.

Pick a provider. The import and the Layer change; the table shows what it supports.

import { Effect } from "effect";
import { Email } from "@effect-kit/emails";
import * as Resend from "@effect-kit/emails/resend";

const program = Effect.gen(function* () {
  const email = yield* Email;
  return yield* email.send(welcome);
});

program.pipe(Effect.provide(Resend.layerConfig()));

What each provider adapter can carry. Select a provider to see its Layer.
Text	HTML	Both bodies	Sender name	CC	BCC	Reply-to	Headers	Attachments	Inline images	Idempotency
yes	yes	yes	yes	yes	yes	yes	yes	yes	yes	yes, replays
yes	yes	yes	yes	yes	yes	yes	yes	yes	yes	no
yes	yes	yes	yes	yes	yes	yes	yes	yes	yes	no
yes	yes	yes	yes	yes	yes	partly, one address	yes	yes	yes	no
yes	yes	yes	yes	yes	yes	yes	yes	yes	no	no
yes	yes	yes	yes	yes	yes	yes	yes	yes	yes	no
yes	yes	yes	no	yes	yes	yes	yes	yes	yes	no
yes	yes	yes	yes	yes	yes	partly, one address	yes	no	no	no
yes	yes	yes	yes	yes	yes	partly, one address	yes	no	no	yes, rejects duplicates
yes	yes	yes	yes	yes	yes	partly, one address	yes	yes	yes	no
yes	yes	yes	yes	yes	yes	yes	yes	yes	no	no
yes	yes	yes	yes	yes	yes	yes	yes	yes	yes	no
yes	yes	yes	yes	yes	yes	yes	yes	yes	no	no
yes	yes	yes	yes	yes	yes	yes	yes	yes	yes	yes, replays
yes	yes	yes	yes	yes	yes	yes	yes	yes	yes	yes, replays
no	yes	no	yes	no	no	no	no	no	no	no

02Playground

Run it in your browser.

Concurrency

#1

#2

#3

#4

#5

#6

outcomes

Simulated provider: message #4 is rate limited.

const outcomes = yield* Email.sendMany(
  orders.map((order) => ({ message: receipt(order) })),
  { concurrency: 3 },
);
// ReadonlyArray<Result<SendReceipt, EmailError>>, in input order

Inspired by Kit Langton's Visual Effect

03Idempotency

Retry without sending twice.

Pass an idempotency key. Each provider handles the repeat its own way, and you get a typed answer.

email.send(welcome, { idempotencyKey: "welcome/ada" })

1sendaccepted, receipt #1
2retry, same keysame receipt #1 returned

Resend: keys kept 24 hours

0requests

0in the inbox

04React templates

One component, two bodies.

EmailReact.render turns a React Email component into the HTML body and the plain-text body. Change the name to see both update.

import * as EmailReact from "@effect-kit/emails/react";

const Welcome = ({ name }: { name: string }) => (
  <Html>
    <Heading>Welcome, {name}</Heading>
    <Text>Your account is ready. Sign in to finish setting up your workspace.</Text>
    <Button href="https://example.com/start">Open dashboard</Button>
  </Html>
);

const content = yield* EmailReact.render(<Welcome name="Ada" />); // { html, text }
yield* email.send({ from, to, subject: "Welcome", ...content });

from hello@example.com

subject Welcome

name

Welcome, Ada

Your account is ready. Sign in to finish setting up your workspace.

Open dashboard

Sent with @effect-kit/emails