Templates

A template is a reusable message body with named variables. They are project-scoped, versioned, and rendered server-side at send time.

Why templates

• Edit copy without redeploying. Marketing changes a subject line, the next send uses the new version.
• Localisation. A single welcome_email template can carry an en, es, de variant; the send picks the locale.
• Auditability. Every send records the template id + version that rendered it.

Variables

Templates use Handlebars-style placeholders:

Subject: Welcome to {{product_name}}, {{first_name}}!

Hi {{first_name}},

Thanks for joining. Your dashboard is at {{dashboard_url}}.

At send time, POST /v1/email/send:

{
  "to": "maya@example.com",
  "template": "tpl_8c4e2a1f",
  "data": {
    "product_name": "Acme",
    "first_name": "Maya",
    "dashboard_url": "https://app.acme.dev/dashboard"
  }
}

Every template field is rendered, not just the body — subject included, so a dynamic subject line is a variable inside the template rather than a field on the request. A variable missing from data renders as an empty string; it does not fail the send. See Template syntax.

Versioning

Each save creates a new version. The active version is the one rendered by default; older versions remain queryable by id. Roll back by re-activating a prior version, no template id changes, no client code changes.