Sequin, a platform that enables building applications and workflows with SQL and Postgres on top of APIs like Stripe, shares insights from developing a real-time data synchronization process between Stripe and Postgres. The synchronization strategy involves two primary processes: an initial backfill to populate the database with historical Stripe data and a continuous event polling mechanism to keep the database updated. The backfill process requires navigating through Stripe's extensive API, converting JSON responses into a structure suitable for Postgres, and managing nested data. The event polling process uses Stripe's events endpoint to capture account changes, ensuring minimal lag and maintaining data accuracy. Unlike webhooks, which can be unreliable due to delivery issues and system downtime, the event polling approach is more robust, offering a reliable means of syncing data. Sequin's system allows users to write back to Stripe, ensuring that local database states remain current and consistent with Stripe's data.