Choose a provider
Configure an existing provider account, compare supported intent and distinguish ordinary email from native jobs.
Choose the provider whose account your application already owns, then check that it can preserve the complete message and recovery policy. Changing Layers keeps the common Email interface; it does not make provider features interchangeable.
Start with field support, local preflight and verification boundaries. Each guide below includes a configured Layer example, message constraints and replay limits.
Ordinary email Layers
| Provider | Configuration focus |
|---|---|
| Resend | Native scoped keys and scheduling |
| Postmark | Message streams, repeated headers and metadata |
| SendGrid | Regional Mail Send and opt-in native personalization |
| Mailgun | Domain-scoped multipart messages and repeated headers |
| MailerSend | Provider-selected attachment MIME and suppression evidence |
| MailPace | Supported headers, attachment extensions and tags |
| Unosend | Explicit attachment MIME and scheduling |
| Lettermint | Provider routes, native keys and sandbox-aware receipts |
| Plunk | Contact upserts and provider-generated text |
| Helo | Live/sandbox channels and short-lived native replay |
| JetEmail | Transactional tokens, domain attestations and forwarded keys |
| Lettr | Immediate/scheduled modes and count-only receipts |
| SparkPost | Regional transmissions and count-aware acknowledgment |
| Primitive | Explicit key requirements and content deduplication policy |
| Mailtrap | Email Sending and multiple acknowledgment IDs |
| Mailchimp Transactional | Account behavior and per-recipient outcomes |
| Scaleway | Project-bound transactional intent |
| ZeptoMail | Live or sandbox mail agents |
| Cloudflare Email Sending | REST account transport and constrained mail flow |
| Amazon SES | Explicit regional SigV4 credentials |
| Microsoft Graph | Host-acquired access token and mailbox identity |
| SMTP | Explicit TLS transport and protocol recipient evidence |
| Brevo | Provider rendering and tracking authority |
| Sequenzy | Transactional HTML and provider-managed profiles |
| SendHeron | Attachment policy and configuration-dependent replay |
Native provider jobs
Loops triggers a provider-managed published template. Iterable triggers a provider-managed campaign. These have separate service interfaces and native { job, options? } batches. They are not ordinary Email Layers or fallback targets.
Compose accounts safely
Use named routing to bind explicit account Layers. Preflight every selected candidate without dropping fields. Only eligible definite rejection advances fallback; unknown or terminal outcomes stop the chain.
Opt-in SendGrid/Mailgun NativeAudience Layers share one provider request. Common individual-preparation wrappers and ordinary routing refuse that mode. See personalization before composing grouped sends.