During March 2025, Cris Ojog developed a robust product identifier flow for the facebook/facebook-for-woocommerce repository, focusing on backend development using PHP. Cris introduced a new field in the Products API response to support reliable checkout URL generation, initially adding woo_commerce_retailer_id and later refactoring it to external_variant_id to ensure accurate propagation of product identifiers throughout the API. This work aligned the API data model with downstream checkout logic, reducing the risk of mismatched product data and improving data fidelity. The feature addressed a core integration challenge, demonstrating depth in API design, data modeling, and backend refactoring within a production environment.