Inline verification
Each record is verified as it passes through the sync, before it lands.
MailerCheck
Polytomic uses MailerCheck to verify email addresses inline as records move through a sync. Map an email field from your data warehouse, database, or SaaS tools, and the verification status is attached to each record before it lands in the destination, without writing code.
Works with any source
Verify emails from your data warehouse, database, CRM, or spreadsheets.
Failures pass through
A verification miss leaves the record intact rather than failing the sync.
Example workflows
Verify email addresses before syncing leads into your CRM
What you can sync
MailerCheck is an enrichment connector. Records flow from your source, get an email verification status attached, and continue on to the destination.
From MailerCheck
Data warehouses including Snowflake, BigQuery, and Databricks
Databases including PostgreSQL, MySQL, and MongoDB
SaaS tools including Salesforce, HubSpot, and Attio
Spreadsheets, cloud storage, and custom APIs
To your destinations
An email field you map as the verification input
A verification status attached to each record
Enriched records continuing to any Polytomic destination
CRM, marketing, and data warehouse destinations
How it works
MailerCheck is an enrichment step rather than a source or destination. You build a model on your data warehouse, database, or SaaS tools, add MailerCheck's email verification to the sync, and map the email field you want checked. Each record is verified as it passes through and arrives at the destination carrying its verification status.
Because verification happens before the write, bad addresses can be filtered or routed differently rather than landing in your CRM and quietly damaging deliverability. Records that fail verification are passed along unchanged and recorded as enrichment failures instead of stopping the sync.
- Connect MailerCheck with an API key
- Add the email verification enrichment to a sync
- Map the email field you want verified
- Each record is verified individually as it flows through
- The verification status is attached to the record
- Monitor enrichment failures alongside sync health in one interface
How to set up
Polytomic authenticates to MailerCheck with a bearer API key. Once connected, email verification becomes available as an enrichment step you can add to a model sync, where you map the email field to verify.
How to get connected
- 1In MailerCheck, generate an API key
- 2In Polytomic, navigate to Connections, then Add Connection, then MailerCheck
- 3Paste your MailerCheck API key
- 4Test the connection
- 5Create a model sync and add the email verification enrichment
- 6Map your email field and click Save
See the documentation for full setup details.
Frequently asked questions
Why teams choose Polytomic
No engineering required
Set up and manage syncs without writing code.
Flexible data modeling
Use SQL to define exactly what data gets synced.
Handles scale automatically
Supports large datasets with incremental syncs and bulk APIs.
Start syncing your data with MailerCheck in minutes
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