Multi-tenant email infrastructure

Email infrastructure
for the products
you ship.

One platform for every app in your portfolio. Send transactional, lifecycle, and marketing email at scale — with templates your team edits in the UI, drip workflows you assemble without writing a job runner, and deliverability we operate so you don't have to. Flat-rate pricing. No per-email fees, ever.

Flat-rate pricing
Tenant-isolated by design
Approval gates & risk controls
LLM template drafting
Outcomes

What you get when you ship
on SkyMailr

One platform. Every product in your portfolio. No more wiring a different ESP into each new app — and no more bill that scales with success.

One platform, every app

Onboard a new product as a tenant in minutes. Templates, sending domains, API keys, suppression lists, rate limits — all isolated per app. No code change when you spin up the next one. Switch context with a dropdown in the operator console.

Edit copy, not code

Marketing tweaks the subject line. Dev ships the feature. Templates live in SkyMailr's UI with versioning and approval gates. An LLM drafts and revises content on request — every draft gates through human approval before it can be sent.

Flat-rate, never per-email

You pay for the platform. You don't pay for the next message you send. Your bill is predictable whether you ship a thousand receipts a month or a million. No metered surprises when a campaign breaks out.

Features

Built for the way real
products actually send mail

Multi-tenant isolation, approval workflows, suppression lists, webhooks, drip campaigns — all out of the box and all governed by the same audit trail.

Versioned templates

Every change is a new version. Approvals required before send. Roll back instantly without a deploy.

LLM-assisted drafting

OpenAI / Anthropic / DeepSeek. Brief in, draft out. Operator approves before anything ships.

Multi-tenant isolation

Every tenant has its own keys, domains, templates, suppression list, rate limits and audit log.

Workflows & drips

Multi-step sequences with wait timers, branches, and tag updates. Enroll users via one API call.

Suppression enforcement

Bounces, complaints, manual blocks. Checked at send and at dispatch. Per-tenant or global scope.

Approval gates

Sends only fire from the currently-approved template version. Audit-grade trail of who approved what.

Per-tenant rate limits

Sliding window throttle. Per-domain warmup caps. Auto-pause on bounce or complaint spikes.

Idempotent sends

Pass an idempotency key. Replays return the same message — no duplicates from caller retries.

DNS-verified domains

SPF / DKIM / DMARC / return-path checked before sends are accepted. Block unverified senders.

Reputation controls

Risk score per tenant. Automatic pause when bounce / complaint thresholds trip.

REST API + Python SDK

Bearer-auth API. Drop-in Python client with helpers for verify, reset, invite, and workflow enroll.

Customer portal

Your customers manage their own templates, API keys, domains, suppressions — without your help.

How it works

One pipeline. Every send.

From your apps to the recipient's inbox — with audit, suppression, rate limits, retries, and webhooks at every hop. We operate the delivery infrastructure end-to-end; you stay in your application code.

YOUR APPS App One api key · domain App Two api key · domain App Three api key · domain API SKYMAILR → Render template (Jinja2) → Check suppression + rate limits → Verify sending domain → Sign, dispatch, retry SMTP SEND INFRASTRUCTURE Dedicated IPs SkyMailr-operated DKIM-signed per-domain keys delivery / bounce / complaint webhooks

1. Your app makes one API call

Bearer-authenticated. Idempotent. Pass a template key and recipient — or hand off a full raw HTML body if you'd rather not template. Async or inline dispatch, your choice.

2. SkyMailr renders + governs

Jinja2 template with strict variable validation. Suppression check, rate limit, sending-domain verification, sender-reputation gate — all in one transactional path.

3. We deliver, you stay in app code

DKIM signing, MX routing, retries, bounce processing, complaint feedback loops — handled by SkyMailr's send infrastructure. You get webhooks back when state changes.

Deliverability

Your mail lands in the inbox.
Not the spam folder.

Deliverability isn't an afterthought — it's the product. SkyMailr operates the send infrastructure that powers every customer, and we tune it for you.

SPF / DKIM / DMARC

Every sending domain is verified end-to-end before SkyMailr will accept a send. Generated DNS instructions per tenant. Per-domain DKIM keys. DMARC alignment enforced.

IP warmup, automated

Per-domain daily and per-minute send caps that grow as you build reputation. New domains start conservative and ramp without manual tuning.

Bounce + complaint feedback loops

Every postmaster signal is ingested, normalized, and reflected back to you as a webhook event. Soft bounces auto-retry. Hard bounces auto-suppress.

Reputation isolation

Transactional and marketing sends are tracked separately. A marketing complaint spike never blocks a password reset. Per-tenant scoring keeps your apps independent.

List-Unsubscribe headers

RFC 8058 one-click unsubscribe for marketing sends — required by Gmail and Yahoo for bulk senders since 2024. SkyMailr injects them automatically.

Plain-text + HTML, always

Every message ships with both a clean text body and the HTML version. Filters love it. Recipients on text-only mail clients love it. So do screen readers.

Security & governance

Audit-grade controls
from day one

Built for teams that need to defend a send to a regulator, a security team, or themselves at 2am.

Approval gates on every template

Sends only fire from the currently-approved template version. Every approval is logged with user, timestamp, and optional note.

Full audit log

Every message, every retry, every suppression, every approval — recorded and queryable. Export per-tenant audit trails on demand.

Bearer auth + key rotation

API keys are hashed at rest. Revocation is immediate. Rotate without downtime: issue a new key, swap, revoke the old.

Suppression as a system

Recipient blocks are first-class. Enforced at message creation AND at the moment of dispatch — no chance of slipping through a race.

RBAC for your team

Owner / Admin / Editor / Viewer / Billing roles. Invite teammates with the right access, revoke instantly when someone leaves.

Webhook signature verification

HMAC-SHA256 signed inbound webhooks with timestamp tolerance. Three-mode rollout: off / warn / enforce. No room for spoofed bounce events.

API

Wire it up
in five lines.

Drop the Python client into your app. Send templated email, enroll users in workflows, manage suppressions — all with first-class types and idempotency built in. Or skip the client and hit the REST API directly from any language.

your_app/notifications.py
from skymailr_client import SkyMailrClient

client = SkyMailrClient(
    base_url="https://app.skymailr.com",
    api_key="sk_live_...",
)

# Send a templated email — idempotent, retryable
client.send_template_email(
    template_key="welcome_new_user",
    to_email=user.email,
    context={"user_name": user.first_name},
    idempotency_key=f"welcome-{user.id}",
)

# Drop a user into a multi-step drip
client.enroll_user_in_workflow(
    workflow_id=settings.WELCOME_DRIP_ID,
    recipient_email=user.email,
    metadata={"template_context": {"first_name": user.first_name}},
)
Use cases

Every category of mail
you actually need to send

Transactional

Critical-path email tied to a specific user action.

  • Signup verification
  • Password resets
  • Receipts & order confirmations
  • Two-factor and security alerts

Lifecycle

Time-based nudges that move users through the product.

  • Welcome drips (D0 / D1 / D7)
  • First-action prompts
  • Re-engagement & winback
  • Plan-change confirmations

Marketing

Broadcast content with compliance baked in.

  • Product newsletters
  • Launch campaigns
  • Promotional offers
  • Auto-injected unsubscribe + List-Unsubscribe headers

System / operational

Internal alerts that need to actually land.

  • Collaborator invites
  • Risk & deliverability alerts
  • Account deletion confirmations
  • Webhook delivery failures
Pricing

Flat-rate. Never per-email.

Pick a plan that fits your team. Your bill doesn't change when a campaign breaks out or your signup flow goes viral.

Free
$0/mo

Prototypes & hobby projects.
500 sends/mo · 1 app · 10 templates

Start free
Starter
$19/mo

Production transactional email.
10k sends/mo · 5 apps · 50 templates

Start free trial
Growth
$99/mo

Multiple products, real volume.
500k sends/mo · 25 apps · 500 templates

Start free trial
Compare plans →

Ship email like a serious product.

Free to start. Flat-rate forever. Multi-tenant from day one.