> ## Documentation Index
> Fetch the complete documentation index at: https://www.dynamic.xyz/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Slack notifications of new signups

> Post in a slack channel when you have a new signup

This guide will teach you how to automatically post a message into a slack channel of your choice with details of a new signup to your dapp.

## Prerequisites

* Completed [the serverless webhooks guide](/recipes/webhooks-serverless)
* A [Slack](https://slack.com/) account
* A [Dynamic](https://dynamic.xyz) account

## Post a message to Slack

As long as you have completed the serverless webhook guide, you'll know how to access the email of a user within your serverless function. Now we have the email, we can post a message to Slack. To do this we'll need to create a [Slack app](https://api.slack.com/apps) and set it up to post messages using incoming webhooks.

[This guide](https://api.slack.com/messaging/webhooks) will get you set up, and once you've completed it you will end up with a webhook URL, that's all you need.

It's time to write the code to send our Slack message. We can do this with anything like Axios or Request, but here we will use [the Slack/webhook library](https://slack.dev/node-slack-sdk/webhook) to make things even easier.

```javascript theme={"system"}
// Slack.js

const { IncomingWebhook } = require("@slack/webhook");

// Read a url from the environment variables
const url = YOUR_SLACK_WEBHOOK_URL;

// Initialize
const webhook = new IncomingWebhook(url);

const sendMessage = async (message) => {
  try {
    return await webhook.send({
      text: message,
    });
  } catch (error) {
    console.error(error);
  }
};

module.exports = sendMessage;
```

```javascript theme={"system"}
// index.js

const webhook = require("./slack");

module.exports.handler = async (event) => {
  const email = event.data.email;

  const message = `New signup: ${email}`;

  await webhook(message);

  return {
    statusCode: 200,
    body: JSON.stringify(
      {
        message: "Go Serverless v3.0! Your function executed successfully!",
        input: event,
      },
      null,
      2
    ),
  };
};
```

## Test it out

As per the serverless webhook guide, we can test this out using:

```bash theme={"system"}
serverless invoke local --function FUNCTION_NAME_HERE --data '{data: {"email":"test@mail.com"}}'
```

We can then deploy using `serverless deploy`, and you're good to go!