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FeaturesNurtureHubUpdated March 21, 2026

Email Delivery & Tracking Infrastructure

Email Delivery & Tracking Infrastructure

Available from v1.0.47

NurtureHub's email delivery and tracking layer handles everything from routing an email out of the platform to recording exactly what a recipient does with it — all without agents needing to configure anything beyond choosing their preferred sending provider.

Delivery

Per-Tenant Delivery Configuration

Each tenant selects a delivery mode independently. The three supported modes are:

ModeDescription
CRM NativeSends via the connected CRM's own mail infrastructure (agentOS, Reapit, Alto, Street, Loop)
Google WorkspaceSends via the tenant's Google Workspace account using OAuth-authenticated SMTP/API
Microsoft 365Sends via the tenant's Microsoft 365 account using OAuth-authenticated Graph API / SMTP

Configuration is scoped strictly per tenant — one agency's delivery mode has no effect on another's.

Scheduled Send Queue

Emails are not sent immediately at creation time. Instead they are placed into a send queue and dispatched at their scheduled send time. Key behaviours:

  • Emails remain in the queue until their scheduled time is reached.
  • If a send attempt fails due to a transient error (network timeout, rate limit, temporary provider outage), the queue automatically retries the send. No manual re-queue step is needed.
  • Persistent failures surface through the standard platform alerting path.

Provider-Agnostic Dispatcher

A single dispatcher component receives items off the send queue and routes them to the correct provider based on the tenant's configured delivery mode. This abstraction means:

  • Adding a new delivery provider in a future release requires changes only to the dispatcher and a new provider adapter — no changes to the queue, scheduling, or sequence logic.
  • Sequence and template logic is fully decoupled from delivery mechanics.

Tracking

All tracking is provider-agnostic: it functions identically regardless of which delivery mode the tenant uses.

Unique Tracking Tokens

When the dispatcher sends an email, a unique tracking token is generated and embedded in that email. The token encodes enough information to identify:

  • The specific email in the sequence
  • The contact it was sent to
  • The tenant it belongs to

All subsequent tracking events reference this token.

Open Tracking

A server-side 1×1 pixel is embedded in the HTML body of each outbound email. When a mail client loads the pixel:

  1. The request hits the NurtureHub pixel endpoint.
  2. The endpoint resolves the tracking token from the request.
  3. An open event is recorded and emitted to the engagement event store.
  4. The endpoint returns a valid 1×1 transparent GIF so mail clients behave normally.

No client-side JavaScript is involved. Open tracking works in any HTML-capable mail client.

Note: Mail clients that block remote image loading (e.g. some desktop Outlook configurations) will not trigger open events. This is a standard limitation of pixel-based tracking.

Click Tracking

Outbound links within email bodies are rewritten at send time to route through a NurtureHub proxy endpoint. When a recipient clicks a link:

  1. The request hits the click proxy endpoint.
  2. The endpoint resolves the tracking token and the intended destination URL.
  3. A click event is recorded and emitted to the engagement event store.
  4. The recipient is immediately redirected to the original destination URL.

The redirect is transparent — recipients land on the intended page with no perceptible delay.

Engagement Event Store

Both open and click events are emitted to the platform's central engagement event store immediately on recording. Downstream consumers of this store include:

  • Real-time intent scoring — contact scores are updated as events arrive.
  • Hot lead alerts — threshold-based alerts fire based on engagement event data.

Because events flow into the same store regardless of delivery provider, all analytics, scoring, and alerting features see a consistent data shape.

Summary of Data Flow

Sequence step scheduled
        │
        ▼
  Send queue (with retry)
        │
        ▼
  Provider-agnostic dispatcher
        │
        ├──► CRM Native
        ├──► Google Workspace
        └──► Microsoft 365
                │
                ▼
        Email delivered to recipient
        (contains tracking pixel + proxied links)
                │
        ┌───────┴────────┐
        ▼                ▼
  Pixel loaded      Link clicked
        │                │
        ▼                ▼
  Open event       Click event
        │                │
        └───────┬────────┘
                ▼
      Engagement event store
                │
        ┌───────┴────────┐
        ▼                ▼
  Intent scoring    Hot lead alerts