Built on open-source useSend

One email layer. Every product you run.

Transactional and marketing email for your entire portfolio—one clean API, one secure SMTP relay, and one place to see what happened.

See the rollout Explore the platform

Made for websites, apps,
stores and internal tools.

order-confirmation
weekly-digest

DELIVERY OVERVIEW

All systems flowing

Live
99.98% delivered

30 day volume

1.28M↗ 12.4%
ACTIVE STREAMSLAST 5 MIN
Rreceiptsshop.example8,942Delivered
Aaccount alertsapp.example3,106Delivered
Nnewsletterstudio.example12,408Sending
42 msAPI response
REST API✦SMTP RELAY✦WEBHOOKS✦DOMAIN HEALTH✦CONTACTS✦CAMPAIGNS✦SUPPRESSIONS✦

FROM ZERO TO SENT

Three steps. No mail maze.

01

Connect a domain

Add the DNS records once. We check SPF, DKIM and return-path health for you.

02

Create an API key

Scope keys to one project, environment and sending limit. Rotate them without downtime.

03

Ship the message

Use the REST API or SMTP relay. Events flow back through signed webhooks.

THE PLATFORM

Infrastructure that feels like a product.

Relayline puts a calm, accountable control layer around the moving parts of email—so every team can send without becoming an email operations team.

TRANSACTIONAL01

Receipts, resets and alerts

Fast, retry-safe delivery with idempotency, scheduling and searchable message logs.

DELIVERABILITY02

Reputation, separated

Every customer gets an isolated sending boundary, suppression list and health signals.

MARKETING03

Campaigns without the bloat

Contacts, consent, templates and broadcasts live beside your product email.

INTEGRATIONS04

API-first. SMTP-friendly.

Modern apps use the API. Older tools keep working through a secure SMTP relay.

ONE CONTROL PLANE

Every app gets its lane. You keep the whole map.

Separate projects, keys and sending limits protect each product while a single overview keeps operations simple.

  • ✓ Project-scoped credentials
  • ✓ Per-tenant reputation controls
  • ✓ Signed event webhooks
  • ✓ Managed or bring-your-own SES
WS

Web store

SA

SaaS app

WP

WordPress

relaylineSECURE MAIL LAYER
✓Inboxdelivered

THE BUILD PLAN

Start with your portfolio. Grow into the SaaS.

We prove the sending core with your own products first, then add the controls required to safely onboard outside customers.

01
Phase 01

Foundation

useSend baseline, infrastructure, sender-domain flow and internal pilot.

Now
02
Phase 02

Control plane

Accounts, projects, scoped keys, quotas, metering and billing.

Next
03
Phase 03

Trust layer

Tenant reputation, abuse review, automatic pausing and audit trails.

Planned
04
Phase 04

Public launch

Documentation, SDKs, onboarding, support and production readiness.

Planned

EARLY ACCESS

Simple plans. Honest limits.

Start free while you connect a project. Upgrade when your sending grows. Final pricing will be validated during the pilot.

STARTER

€0/ month

For a small site proving its first email flow.

  • 3,000 emails / month
  • 1 domain and 1 project
  • API + SMTP access
  • 3-day event history
Join the pilot →
PORTFOLIO PICK

BUILDER

€19/ month

For teams running several production products.

  • 50,000 emails / month
  • 10 domains and projects
  • 30-day event history
  • Priority email support
Join the pilot →

SCALE

Let's talk

For larger teams with isolation and compliance needs.

  • Custom sending volume
  • Bring your own AWS SES
  • Dedicated reputation lane
  • Custom data retention
Talk to us →

GOOD QUESTIONS

Before you hit send.

Is Relayline another email server?

No. Relayline is the service layer your apps talk to. It uses the open-source useSend platform for sending workflows and Amazon SES for the final delivery.

Can every website have its own API key?

Yes. Each site or app becomes a project with separate keys, domains, limits, logs and webhook destinations.

Will it support both API and SMTP?

Yes. New applications can use the REST API, while WordPress, Supabase and legacy software can connect through SMTP.

Can customers bring their own AWS account?

That is part of the scale plan. The first release uses managed sending, while larger customers can connect isolated SES credentials later.

THE PILOT STARTS HERE

Give every product a better way to send.

The foundation is ready. Next: connect the first domain, send the first live event, and shape the service around real usage.

Plan the first integration