Bolt.new AI and Sendinblue integration: Step-by-Step Guide 2025

You integrate Bolt.new with Sendinblue (now called Brevo) the same way any full‑stack app does: you call Brevo’s REST API from the Bolt.new server environment using your API key stored in environment variables. Bolt doesn’t have a built‑in “Sendinblue connector”. You create the integration yourself by writing a small API route inside Bolt’s backend and using Brevo’s official endpoints (usually via simple fetch/axios calls). That’s the entire pattern.

The flow is: you place your Brevo API key in Bolt’s environment variables, write a backend route that talks to Brevo’s transactional email API, then call that route from your frontend or from Bolt’s AI-generated components. Everything else (email templates, contact lists, automations) is handled in the Brevo dashboard.

 

What you actually need

 

• A Brevo (Sendinblue) API key — found at https://app.brevo.com/settings/keys
• A Bolt.new project with server-side code enabled
• One environment variable: BREVO_API_KEY
• A backend route that sends the email via Brevo’s REST API

 

Step-by-step: How to integrate Bolt.new with Sendinblue/Brevo

 

This is the clean, real, production-valid approach.

• Put your API key in Bolt.new env vars
  In Bolt, open your project settings → environment → add:
  BREVO_API_KEY = your_real_api_key_here
• Create a backend route that calls Brevo’s email endpoint
  This is a standard Node backend file in Bolt.

 

// backend/sendEmail.js

import express from "express";
import fetch from "node-fetch";

const router = express.Router();

router.post("/send-email", async (req, res) => {
  const { to, subject, html } = req.body;

  // Brevo's transactional email API endpoint
  const url = "https://api.brevo.com/v3/smtp/email";

  try {
    const response = await fetch(url, {
      method: "POST",
      headers: {
        accept: "application/json",
        "api-key": process.env.BREVO_API_KEY,   // secure API key from Bolt env vars
        "content-type": "application/json"
      },
      body: JSON.stringify({
        sender: { name: "Your App", email: "[email protected]" },
        to: [{ email: to }],
        subject: subject,
        htmlContent: html
      })
    });

    const data = await response.json();

    if (!response.ok) {
      return res.status(500).json({ error: data });
    }

    res.json({ success: true, brevoResponse: data });
  } catch (err) {
    res.status(500).json({ error: err.message });
  }
});

export default router;

 

• Register the route in your backend index

 

// backend/index.js

import express from "express";
import sendEmailRoute from "./sendEmail.js";

const app = express();
app.use(express.json());

app.use("/api", sendEmailRoute);

export default app;

 

• Call this backend route from your frontend

 

// frontend example (React component or Bolt-generated UI)

async function sendTestEmail() {
  const res = await fetch("/api/send-email", {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({
      to: "[email protected]",
      subject: "Hello from Bolt + Brevo",
      html: "<p>Integration successful!</p>"
    })
  });

  const data = await res.json();
  console.log(data);
}

 

Important notes the junior dev must understand

 

• Bolt.new never directly stores your API key in code. It stays in environment variables.
• You never call Brevo directly from the frontend because that would expose your API key.
• No SDK required. Brevo’s REST API works with plain HTTP fetch.
• Templates are optional. You can send raw HTML or reference Brevo template IDs by adding templateId.
• The backend route acts as your secure gateway between Bolt’s frontend and Brevo.

That’s the actual, real‑world way to integrate Bolt.new with Sendinblue/Brevo: store the API key in env vars, create a backend route, call Brevo’s REST endpoint, and trigger that route from your UI or AI agents inside Bolt.