Most Magento↔Mailchimp problems come from flaky third-party connectors: silent sync failures, duplicated subscribers, missing order data and abandoned-cart feeds that quietly stop firing after an upgrade. ECOSIRE's Mailchimp Connector is a build-to-order Magento 2 extension — we build it as a proper module under app/code/Ecosire/MailchimpConnector, install it on your Magento Open Source or Adobe Commerce instance, and stand behind it.

The connector subscribes to Magento events via observers (customer_save_after, newsletter_subscriber_save_after, sales_order_place_after, checkout_cart_save_after) and uses the Mailchimp Marketing API v3 to push Audiences/lists, segments and tags, e-commerce stores, products, carts and orders. Heavy syncs run through a dedicated message queue consumer and cron jobs so they never block checkout or the admin. Configuration lives in a namespaced system.xml section under Stores → Configuration, gated by admin ACL so only authorized roles can edit API keys (stored encrypted via Magento's config encryption).

Because it's built for your store, the merge-field and tag mapping matches your actual customer attributes and the opt-in / double opt-in and consent flow honours your GDPR setup. Abandoned-cart data is fed to Mailchimp's e-commerce endpoints so its Customer Journey / abandoned-cart automations have real cart contents to work with.

You get the full source code (no encrypted blobs, no per-seat licence server), composer-installable, with a clear upgrade path. ECOSIRE installs it, validates the first full sync, and supports it — this is honest software-as-a-service-of-engineering, not an instant Marketplace download.