Deliverability, as infrastructure

An Email Deliverability Service That Acts First

Authentication checks, domain warmup, and reputation monitoring in one API, so an email deliverability service stops reporting problems and starts preventing them.

Start a warmup run See what it controls
Dark monitoring dashboards showing deliverability metrics trending upward on two monitors
What it controls

Six deliverability controls that run without you watching

Deliverability is not a feature you tune once. It is a set of constraints that need to hold on every batch.

Authentication verified first

SPF, DKIM and DMARC alignment get checked before the first send, because a broken record quietly undermines everything built on top of it.

Warmup on a fixed ramp

Go from 50 sends a day to 100k over roughly four weeks. Volume rises on a curve instead of a spreadsheet someone forgets to update.

Auto-pause on reputation risk

Bounce rate, spam complaints and blocklist hits are checked per batch. Cross a threshold and the ramp stops before the next send.

Trace per send

Open, click, bounce and spam signals for every message, streamed over SSE, with the raw events available when you need to debug.

Export to your stack

Send the same events to Datadog or Grafana and alert on deliverability the way you alert on latency and error rate.

SDKs with safe retries

Node, Python and Go SDKs with idempotency keys and exponential backoff, so a retry never turns into a duplicate send.

How it runs

From a cold domain to full volume in four steps

Mostly unattended. You set the target, the system keeps the constraints.

  1. 1

    Connect the sending domain

    Point the domain at the service. Authentication and DNS records are verified before anything leaves the building.

  2. 2

    Set target volume and window

    Pick where you want to land, often 100k a day, and over what window. Four weeks is a common starting point.

  3. 3

    Let the ramp run

    Daily volume grows on the configured curve while the checks run against every batch, not once a week.

  4. 4

    Pause, alert, resume

    When a signal trips a threshold, sending halts and the alert names the signal. Fix the cause, then resume the ramp.

Who this is for

For a team debugging a sudden drop in inbox placement

When placement falls, the first hour goes to guessing: is it DNS, a list problem, or a reputation hit? Per-send traces and threshold alerts turn the guess into a diagnosis. You see which signal moved, on which batch, and whether the ramp already paused itself.

  • Trace for every send, with bounce and spam signals
  • Alerts that name the signal that tripped
  • Resume path once the root cause is fixed
Laptop terminal showing send logs next to a notebook sketch of mail routing
Who this is for

For a product team scaling a transactional pipeline

Transactional volume grows in steps, not smoothly. A new onboarding flow ships or a feature reaches general availability, and daily sends jump overnight. Ramping the new volume in behind the scenes keeps password resets and receipts landing in the inbox while the pipeline scales.

  • Handles step changes in volume, not just steady growth
  • Existing transactional sends stay unaffected during the ramp
  • Alerts before a spike becomes an incident
Server rack aisle with blue status lights representing email infrastructure

Common questions

What is an email deliverability service?
It is the layer that decides whether your messages reach the inbox: authentication checks, domain warmup, reputation monitoring, bounce handling, and alerting. A good one runs these continuously instead of leaving them to a quarterly audit.
How is it different from an ESP's built-in deliverability tab?
Most ESP dashboards report inbox placement after the damage is done. A deliverability service acts before the send: it verifies SPF, DKIM and DMARC alignment, throttles volume on a ramp, and pauses sending when bounce or complaint rate crosses a threshold.
How long does domain warmup take?
About four weeks is the usual window for taking a new domain from 50 sends a day to 100k a day. The right curve depends on your list quality and content, which is why the ramp is configurable per domain instead of fixed.
Will it fix a domain that is already in spam folders?
Not by itself. Authentication errors and bad list hygiene are the usual root causes, and those need fixing first. The service surfaces which signal is failing, then lets you resume the ramp once the cause is gone.
Do I need SPF, DKIM and DMARC before I start?
Yes, and the service checks alignment before the first send. A misconfigured DKIM record is the most common reason a ramp stalls or a bounce rate spikes for no obvious reason.
Can I send transactional email while a domain warms up?
Yes. The ramp controls how fast new volume grows, not whether existing sends continue. Password resets and receipts keep flowing while the new volume ramps in behind them.
What can I see for each message?
Every send has a trace with open, click, bounce and spam signals, streamed over SSE. You can export the same events to Datadog or Grafana and alert on them with the rest of your infrastructure.
Is it worth it at a few thousand emails a month?
Usually not on its own. It earns its keep when volume steps up materially, for example a new onboarding flow, a feature going to general availability, or an outbound program scaling past a few hundred sends a day.

Put deliverability on the same dashboard as everything else

Connect a domain, set a target, and let the ramp run. Pause and alerts are automatic.

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