Segment vs Hull

Customer Data Pipelines for Email Workflows

This post explores my experiments using Segment and Hull to drive data-driven email workflows. I’ll highlight what works, what falls short, and how I connect everything to SFMC.

Event Capture and Validation

Here’s what I tried: collect events from web and mobile apps, enrich them with customer data, validate them, and push to SFMC. First step, event capture. Segment makes it easy with sources and destinations. Hull has a flexible event transformation layer but sometimes requires more custom code.

In Segment, I set up sources for web and mobile, added event schemas, and created “tracking plans”. Any missing fields would trigger alerts. Hull’s approach was more programmatic. I could create pipelines that cleaned data, mapped identifiers, and enriched profiles, but it required me to script some transformations manually.

Pitfalls and Workarounds

Duplicate profiles across devices: Hull needed identity stitching logic; Segment handled most with built-in traits.
Missing required fields for SFMC: added defensive SQL checks in staging tables before triggering sends.
Complex event transformations: Hull gave full control but slowed iteration; Segment was faster for standard enrichment.

Plugging into SFMC

The final pipeline looks like this:

[Web/Mobile Event] --> [CDP: Segment / Hull]
                       |
                       v
             [Validation / Staging]
                       |
                       v
        [SFMC Triggered Send / Workflow]

Any event that fails validation is logged, and alerts fire to my inbox. This mimics the same defensive mindset I used in Scaling SFMC to 6M Contacts. The goal is predictable, reliable messaging without surprises.

Takeaways:

Segment is quicker to implement and ideal for standard event pipelines and direct SFMC integration.
Hull offers more control, better for custom identity stitching and complex transformations, but requires more setup.
Both tools benefit from staging tables and validation queries to protect deliverability in regulated environments.

Next step: I’ve started combining the two approaches: use Segment for fast event capture and Hull for advanced transformations and identity stitching. Gives the best of both worlds for SFMC workflows.

Also see my SQL Patterns for Email Segmentation post for defensive querying tips that apply here as well.