Ark

Ark is the email API designed specifically for developers who build multi-tenant software platforms. If you're creating a CRM, helpdesk, invoicing tool, scheduling app, or any product where your customers need to send emails from their own domains, Ark is built for you. Unlike generic email services that assume one company, one sender, Ark is purpose-built from the ground up to handle hundreds or thousands of unique customer domains effortlessly. Its core value is eliminating the immense infrastructure headache of managing SPF, DKIM, domain verification, and per-customer email logs. With Ark, you integrate once and then let your customers connect their own domains in minutes through a self-service process. This means you can offer true white-label email, where invoices come from [email protected] and notifications from [email protected], making your platform feel like a native part of their business. Ark provides AI-readable documentation and tools to speed up integration, but its real superpower is giving you a single dashboard to manage, monitor, and debug email for every single customer, so you can stop building email infrastructure and focus on your actual product.

Built for Multi-Tenant Platforms

Ark is uniquely designed for platforms with multiple customers, making tenant isolation the default. Each customer gets their own completely separate environment for domains, sending logs, analytics, and deliverability metrics. This means you never have to build complex separation logic on top of a generic email API. Everything is organized per customer from the start, saving you months of development time and making support and debugging straightforward.

Automated Domain & DNS Configuration

Onboarding a new customer domain is simple and fast. Ark automatically detects the customer's DNS provider (like Cloudflare, GoDaddy, or Route53) and provides them with the exact, simple steps to add the necessary records. For some providers, Ark can even configure the DNS automatically. This eliminates lengthy support calls explaining TXT and CNAME records, enabling a truly self-service experience that scales.

Per-Customer Visibility & Debugging

When a customer reports an email issue, you can find the answer instantly. Ark provides isolated logs and analytics for every single customer domain. You can search, filter, and debug delivery problems across your entire customer base from one unified dashboard. This deep, per-customer visibility turns a nightmare troubleshooting session into a simple, quick check, ensuring high customer satisfaction.

AI-Native Integration Tools

Ark is built for the modern developer workflow. It comes with AI-readable documentation and a native MCP server with 26 tools, allowing AI coding assistants like Claude, Cursor, or GitHub Copilot to understand the API perfectly. This enables your AI assistant to generate production-ready code for features like user verification or password resets on the first try, helping you ship in minutes instead of days.

Customer Relationship Management (CRM) Tools

CRM platforms need to send emails like lead notifications, meeting reminders, and outreach sequences on behalf of their users. With Ark, each sales team can send emails from their own company domain (e.g., [email protected]), maintaining brand consistency and improving deliverability, all managed seamlessly from the CRM's single interface.

Helpdesk & Customer Support Software

Helpdesk platforms send ticket updates, agent replies, and support notifications. Ark allows each business using the software to send these emails from their own support domain (like [email protected]). This white-label experience makes the helpdesk feel like an integrated part of the customer's business operations.

Invoicing & Billing Platforms

Invoicing tools send critical financial documents that must come from a trusted, customer-owned domain. Ark enables these platforms to send invoices, payment receipts, and reminders from addresses like [email protected], which looks professional, builds trust, and reduces the chance of invoices being marked as spam.

Scheduling & Booking Applications

Scheduling apps send confirmation emails, calendar invites, and reminders. Using Ark, a fitness studio or consultant can send these appointments from their own business domain (e.g., [email protected]). This reinforces their brand with every customer interaction and ensures high delivery rates for time-sensitive communications.

Who is Ark for?

Ark is specifically built for developers and companies building B2B software platforms (SaaS) where their customers need to send email. This includes products like CRMs, helpdesks, invoicing tools, scheduling apps, marketing automation, and more. If your product sends email "on behalf of" your users, Ark is designed for you.

How does domain onboarding work for my customers?

The process is designed to be self-service. When your customer needs to add their domain, your app directs them to a simple interface (or uses Ark's API). Ark identifies their DNS provider and gives them clear, step-by-step instructions. For supported providers, it can even set up the DNS records automatically, often completing verification in just a couple of minutes without your support team's help.

How is Ark different from Resend or SendGrid?

Services like Resend, SendGrid, and Amazon SES are built for a single company to send its own emails. Ark is built for platforms with many customers. The key difference is multi-tenancy: Ark provides built-in, secure isolation for each customer's domains, logs, and analytics. Trying to achieve this with other tools requires building a complex management layer on top of their API.

What kind of support and reliability does Ark offer?

Ark is built for production use with sub-second email delivery speeds and a 99.9%+ deliverability rate. It includes comprehensive features for monitoring and debugging, giving you and your customers transparency into email performance. You can scale from a few domains to thousands without worrying about infrastructure.

Ark offers simple, scalable pricing that grows with your customer base. You can start with a plan at $29 per month, which includes 10 customer domains and 50,000 emails. As your platform grows, you can scale up to plans supporting 1,000 domains or more. All plans include unlimited team members, per-customer isolation, and full access to the dashboard and API. You can begin with a 7-day free trial with no credit card required to test the integration.