Mailchimp Webhook (Audit Only)

1. Subscriber unsubscribes (or is cleaned) in Mailchimp.
2. Mailchimp sends a webhook to POST /webhooks/mailchimp with event type (e.g. unsubscribe, cleaned) and member email/list.
3. NOMA Sync verifies the webhook, parses the payload, and logs a row to sync_log (source: mailchimp). No LGL API calls are made.
4. LGL subscription status (Subscribed, Unsubscribed, Bounced, etc.) is updated by LGL's built-in Mailchimp integration (nightly sync). Configure that in LGL: Settings → Integration → Mailchimp.

See Unsubscribe Flow for the full flow and where to check in Dashboard vs LGL.

Givebutter / Square → Mailchimp (Contact Sync)

When someone donates or registers via Givebutter (or buys via Square, if that integration is enabled), NOMA Sync:

1. Syncs the transaction to LGL (constituent, gift).
2. Adds or updates the contact in Mailchimp — list member, merge fields (FNAME, LNAME, etc.), and tags per list mapping and tag rules. This is the main "pass-through" from transactional sources into Mailchimp.

List mapping determines which Mailchimp list(s) to use; tag rules can apply tags (e.g. "Donor", "Event Registrant"). This flow is Givebutter/Square → NOMA Sync → Mailchimp, not Mailchimp → LGL.

Sync Direction Summary

Direction	Who	What
Givebutter → Mailchimp	NOMA Sync	Add/update list member, tags, merge fields.
Square → Mailchimp (optional)	NOMA Sync	Same.
Mailchimp webhook → NOMA	NOMA Sync	Audit only: log to sync_log.
Mailchimp ↔ LGL (subscription status)	LGL's integration	Nightly sync; "MailChimp Status" in LGL.