The Postman SMTP family of plugins, which the Postmark transactional plugin descends from, writes every send to wp_posts using the postman_smtp_log post type. Status, recipient, subject, and the full transcript land in wp_postmeta under keys prefixed with _eml_ and _postman_.

No. SleekView reads the existing postman_smtp_log custom post type that the Postmark plugin already creates. No bridge plugin, no custom code, no schema migration. Activate SleekView, point at the log post type, and the charts render against existing rows immediately.

Yes. Group by the _eml_to postmeta value and apply a domain extraction at the visualization layer, or pre-filter on a substring like gmail.com or t-online.de. The resulting horizontal bar makes top failing domains obvious without exporting a single row to a spreadsheet.

No. SleekView is a WordPress-side tool. It reads only the postman_smtp_log entries the plugin has already written to your local database. For Postmark-side metrics like bounce reasons or spam complaints, you still log into Postmark, but the WordPress dashboard answers most day-to-day questions.

Most Postman SMTP installs include a log retention setting that prunes old entries. SleekView charts pick up the pruning automatically since they query live data. You can also configure SleekView's per-chart cache TTL so heavy historical queries do not hit the database on every page view.

Yes. SleekView treats each chart independently, so one dashboard can hold a postman_smtp_log success rate KPI right next to a wc_orders revenue KPI. Comparing transactional volume to order volume side by side surfaces issues like missing customer-new-account emails.

Yes. Build a dashboard restricted to a support role with charts that filter to specific subject patterns, status, or date windows. Support sees the deliverability picture they need in WP admin while keeping zero direct access to wp_postmeta or phpMyAdmin.

Charts depend on the postman_smtp_log post type and the documented meta key naming. Those have been stable through multiple plugin generations. If a future version renames a key, you change the field in one place in SleekView's chart configuration without touching the underlying plugin or database.