The four options
- SMTP — anything that speaks SMTP. Universal escape hatch. Works with Postmark, Brevo, your own Postfix, Gmail app passwords, etc.
- Amazon SES — cheapest at scale ($0.10 per 1,000). Production access requires a quick AWS support ticket.
- SendGrid — easiest deliverability. Generous free tier (100/day forever).
- Mailgun — solid mid-market option. EU and US regions.
Quick recommendation
- You're indie / startup: SendGrid free tier or SES.
- You send 10k+ /mo: SES — by a wide margin on price.
- You're in EU and care about it: Mailgun EU region.
- You already have a transactional provider: SMTP, point at it.
Switching is two clicks
Maillayer stores templates, contacts, and analytics independently of the provider. Brand → Provider → swap credentials. Past sends keep their event history.
What happens behind the scenes
Each brand has one active provider config. When you send (campaign, sequence, transactional, or test), Maillayer:
- Resolves the brand's provider + secrets (encrypted at rest with
AUTH_SECRET). - Sends via the provider's HTTPS API or SMTP.
- Records the message ID and timestamps for tracking.
- Receives bounce/complaint webhooks back at
/api/webhooks/<provider>.
Pick whichever fits your volume and constraints.