shellphone.app/app/api/newsletter/_mailchimp.ts

import getConfig from "next/config";
import got from "got";

const { serverRuntimeConfig } = getConfig();

export async function addSubscriber(email: string) {
	const { apiKey, audienceId } = serverRuntimeConfig.mailChimp;
	const region = apiKey.split("-")[1];
	const url = `https://${region}.api.mailchimp.com/3.0/lists/${audienceId}/members`;
	const data = {
		email_address: email,
		status: "subscribed",
	};
	const base64ApiKey = Buffer.from(`any:${apiKey}`).toString("base64");
	const headers = {
		"Content-Type": "application/json",
		Authorization: `Basic ${base64ApiKey}`,
	};

	return got.post(url, { json: data, headers });
}