About
About Email SDK
Email SDK is an open-source TypeScript SDK for sending transactional email. It gives an application one typed client and one message shape, then routes each send to providers such as Resend, SMTP, Postmark, SendGrid, Mailgun, Unosend, AWS SES, and more.
What it is
A single send() call with one normalized EmailMessage shape. Provider-specific behavior lives in adapters imported from their own entry points, so switching or adding a provider does not mean rewriting every place your app sends mail. The core ships with zero dependencies and includes its own SMTP transport.
Why it exists
Most applications start on one email provider and later need a second one for deliverability, cost, or regional routing. Email SDK keeps provider differences behind a consistent API with explicit routing, automatic retries on transient failures, and fallback routes between adapters that support the same fields — so changing providers is a configuration change, not a refactor.
Who maintains it
Email SDK is built and maintained by OpenCore as an open-source project. The source, issues, and releases are public on GitHub, and the package is published to npm.
Where to go next
Read the documentation to install the package and send your first email, browse the adapters for each provider, or get in touch through the contact page.